Redis学习笔记
Redis
Redis（Remote Dictionary Server )，即远程字典服务，是一个开源的使用ANSI C语言编写、支持网络、可基于内存亦可持久化的日志型、Key-Value数据库，并提供多种语言的API。
redis是当前最热门的NoSQL技术之一。
Redis 是一个开源（BSD许可）的，内存中的数据结构存储系统，它可以用作数据库、缓存和消息中间件。 它支持多种类型的数据结构，如 字符串（strings）， 散列（hashes）， 列表（lists）， 集合（sets）， 有序集合（sorted sets） 与范围查询， bitmaps， hyperloglogs 和 地理空间（geospatial） 索引半径查询。 Redis 内置了 复制（replication），LUA脚本（Lua scripting）， LRU驱动事件（LRU eviction），事务（transactions） 和不同级别的 磁盘持久化（persistence）， 并通过 Redis哨兵（Sentinel）和自动 分区（Cluster）提供高可用性（high availability）。
安装 Redis
1、下载安装包
2、使用xftp工具将安装包上传至 Linux 中
3、解压压缩包
# 切换到上一步上传进来的目录
cd /home/
# 解压文件
tar -xzvf redis-6.2.2.tar.gz
# 移动到 /opt 目录
mv redis-6.2.2 /opt/
4、安装 gcc
# 安装gcc 期间服务器需要有网络，不然会安装失败
yum install gcc-c++
5、开始安装
# 进入Redis 目录
cd /opt/redis-6.2.2/
# 进行安装
make
# 进入redis 的 src目录
cd src/
# 安装运行启动程序
make install
6、修改配置文件
# 进入Redis安装后的默认启动路径
cd /usr/local/bin/
# 创建存放配置的文件夹
mkdir redisconf
# 将启动的配置文件移动到创建的目录中
mv /opt/redis-6.2.2/redis.conf /usr/local/bin/redisconf/
# 修改配置文件 没有vim的请先自行安装
vim /usr/local/bin/redisconf/redis.conf
# 在配置文件中找到 daemonize 修改为 yes 保存，如下图
7、启动测试
# 切换启动目录
cd /usr/local/bin/
# 启动服务
redis-server redisconf/redis-conf
# 启动客户端
redis-cli -p 6379
# 出现下图启动成功
Redis 压力测试
Redis基本命令
数据库
Redis 默认有16个（0~15）数据库，默认使用第0个 我们可以 select命令切换数据库
# select 切换数据库
127.0.0.1:6379> select 15
OK
127.0.0.1:6379[15]>
查看数据库大小：DBSIZE
# DBSIZE 查看数据库大小
127.0.0.1:6379> DBSIZE
(integer) 1
127.0.0.1:6379>
查看数据库的所有 key：keys *
# 查看全部的key
127.0.0.1:6379> keys *
1) "name"
127.0.0.1:6379>
添加key：set
# 添加数据库的 key
127.0.0.1:6379> set age 18
OK
127.0.0.1:6379>
获取key的值：get
# get key名称 获取key的值
127.0.0.1:6379> get name
"fdfgfdd"
127.0.0.1:6379>
判断key是否存在：exists
# 判断key是否存在 存在放回 1 不存在返回 0
127.0.0.1:6379> EXISTS name
(integer) 1
127.0.0.1:6379> EXISTS name1
(integer) 0
设置key 在多少秒后过期 ： expire
# 设置key 在多少秒后过期
127.0.0.1:6379> EXPIRE name 10
(integer) 1
# 查看过期时间 -2 为已过期，-1为无限时间，其余的都是剩余多久过期
127.0.0.1:6379> ttl name
(integer) 3
127.0.0.1:6379> move name 1
(integer) 1
移动key到另外一个数据库：move
# 移动key到另外一个数据库
127.0.0.1:6379> move name 1
(integer) 1
获取key的类型：type
# 获取key的类型
127.0.0.1:6379[1]> TYPE nameset
string
清空数据库：flushdb flushall
# 清空当前数据库 FLUSHDB
127.0.0.1:6379> FLUSHDB
OK
# 情况所有数据库 FLUSHALL
127.0.0.1:6379> FLUSHALL
OK
127.0.0.1:6379>
基本数据类型
String类型
追加字符串：append
# append 追加字符串
127.0.0.1:6379> set k1 v1
OK
127.0.0.1:6379> set k2 v2
OK
127.0.0.1:6379> set k3 v3
OK
127.0.0.1:6379> APPEND k1 hello #追加字符串
(integer) 7
127.0.0.1:6379> get k1 #查看追加后的值
"v1hello"
127.0.0.1:6379>
查看字符串长度：strlen
# 查看字符串长度
127.0.0.1:6379> STRLEN k1
(integer) 7
值的增加减少：incr（增加） decr(减少)
# 值的增加减少（自能是数字类型）
127.0.0.1:6379> INCR k4
(integer) 1
127.0.0.1:6379> INCR k4
(integer) 2
127.0.0.1:6379> deCR k4
(integer) 1
127.0.0.1:6379> decr k4
(integer) 0
通过步长增加减少:incrby(步长增加) decrby(步长减少)
# 值按照增加减少（自能是数字类型）
127.0.0.1:6379> INCRBY k4 4
(integer) 4
127.0.0.1:6379> INCRBY k4 4
(integer) 8
127.0.0.1:6379> DECRby k4 3
(integer) 5
127.0.0.1:6379> DECRBY k4 3
(integer) 2
通过下标获取字符串的值（截取字符串）：getrange
# 通过下标获取字符串的值：getrange key名 开始下标 结束下标(-1代表全部)
127.0.0.1:6379> clear
127.0.0.1:6379> set k1 hello,wangyxing
OK
127.0.0.1:6379> get k1
"hello,wangyxing"
127.0.0.1:6379> GETRANGE k1 0 5
"hello,"
127.0.0.1:6379> GETRANGE k1 0 -1
"hello,wangyxing"
127.0.0.1:6379>
替换字符串：setrange
# 从某个位置替换字符串
127.0.0.1:6379> set k2 abcdefg
OK
127.0.0.1:6379> SETRANGE k2 2 xx
(integer) 7
127.0.0.1:6379> get k2
"abxxefg"
127.0.0.1:6379>
设置值并给出过期时间：setex
# 设置值并给出过期时间 setex key名 过期时间 值
127.0.0.1:6379> setex k3 30 hello
OK
判断是否能设置值：setnx
# 判断是否能设置值 如果存在则不设置，不存在则设置
# setnx key名 value
127.0.0.1:6379> set ifk1 hello
OK
127.0.0.1:6379> setnx ifk1 hhh
(integer) 0
127.0.0.1:6379>
批量设置key：mset msetnx
# 批量设置key
# mset key value [key value]
127.0.0.1:6379> mset k1 v1 k2 v2 k3 v3
OK
127.0.0.1:6379> keys *
1) "k3"
2) "k2"
3) "k1"
# msetnx 是一个原子性操作，要么一起成功，要么一起失败
127.0.0.1:6379> MSETNX k1 v1 k4 v4 # k1上面存在所以设置失败
(integer) 0
127.0.0.1:6379> MSETNX k5 v5 k4 v4
(integer) 1
批量获取key：mget
# 批量获取key mget key [key]
127.0.0.1:6379> MGET k1 k2 k3 k4 k5
1) "v1"
2) "v2"
3) "v3"
4) "v4"
5) "v5"
设置对象
# 设置对象，mset 同时设置对象的多个属性 下面的例子是设置 1 号用户的属性
127.0.0.1:6379> mset user:1:name zhangsan user:1:age 18 user:1:sex nan
OK
127.0.0.1:6379> MGET user:1:name user:1:age user:1:sex
1) "zhangsan"
2) "18"
3) "nan"
先获取值，在替换值：getset
# 先获取get的值，在设置一个新的值
127.0.0.1:6379> getset k1 v1
(nil)
127.0.0.1:6379> getset k1 v2
"v1"
127.0.0.1:6379> getset k1 v3
"v2"
String的使用场景
计数器：
统计多单位的数据：粉丝数，关注数，评论数
List类型
因为 Redis的设计原理，我们可以把Redis中的List设计成 栈 队列 阻塞队列等等。
设计原理
存值与取值（从左边开始）: lpush lpop (rpush 和 rpop没有演示)
# 向列表中存入值
# lpush 列表名 [value]
127.0.0.1:6379> LPUSH mylist hello 0 wangyuxing 2 v1
(integer) 5
# lpop 列表名 [出栈个数，(默认是1)]
127.0.0.1:6379> LPOP mylist
"v1"
127.0.0.1:6379> LPOP mylist 2
1) "2"
2) "wangyuxing"
查看值：lrange
# lrange key名 开始范围 结束范围
127.0.0.1:6379> LPUSH mylist hello 0 wangyuxing 2 v1
(integer) 5
127.0.0.1:6379> LRANGE mylist 0 -1
1) "v1"
2) "2"
3) "wangyuxing"
4) "0"
5) "hello"
127.0.0.1:6379> LRANGE mylist 0 3
1) "v1"
2) "2"
3) "wangyuxing"
4) "0"
通过下标获取值：lindex
127.0.0.1:6379> LPUSH mylist hello 0 wangyuxing 2 v1
(integer) 5
127.0.0.1:6379> LINDEX mylist 0
"v1"
127.0.0.1:6379> LINDEX mylist 2
"wangyuxing"
查看长度： llen
# 获取列表长度
127.0.0.1:6379> LLEN mylist
(integer) 5
移除指定的值：lrem
# lrem key名 移除个数（从左到右计数） value
127.0.0.1:6379> lrem mylist 1 wangyuxing
(integer) 1
127.0.0.1:6379> LRANGE mylist 0 -1
1) "v1"
2) "2"
3) "0"
4) "hello"
截取List：ltrim
127.0.0.1:6379> LPUSH mylist hello 0 wangyuxing 2 v1
(integer) 5
127.0.0.1:6379> LRANGE mylist 0 -1
1) "v1"
2) "2"
3) "wangyuxing"
4) "0"
5) "hello"
127.0.0.1:6379> LTRIM mylist 1 3 #截取 1 到 3
OK
127.0.0.1:6379> LRANGE mylist 0 -1 #查看截取后的值
1) "2"
2) "wangyuxing"
3) "0"
127.0.0.1:6379>
组合命令：rpoplpush(只能从左边出，新列表右边进)
# 移动列表的第一个元素到新的列表中
127.0.0.1:6379> LPUSH mylist hello 0 wangyuxing 2 v1
(integer) 5
127.0.0.1:6379> RPOPLPUSH mylist newlist
"hello"
127.0.0.1:6379> LRANGE mylist 0 -1
1) "v1"
2) "2"
3) "wangyuxing"
4) "0"
127.0.0.1:6379> LRANGE newlist 0 -1
1) "hello"
判断列表是否存在 ：exists
127.0.0.1:6379> EXISTS mylist
(integer) 1
更新列表中的值：lset
# 使用lset 更新列表的值，不存在会报错
127.0.0.1:6379> LRANGE mylist 0 -1
1) "v1"
2) "2"
3) "wangyuxing"
4) "0"
# lset mylist 下标 value
127.0.0.1:6379> lset mylist 1 3
OK
127.0.0.1:6379> LRANGE mylist 0 -1
1) "v1"
2) "3"
3) "wangyuxing"
4) "0"
插入元素：linsert
# 插入元素
127.0.0.1:6379> LRANGE mylist 0 -1
1) "v1"
2) "3"
3) "wangyuxing"
4) "0"
# 向mylist中的0元素的前面插入insert
127.0.0.1:6379> LINSERT mylist before 0 insert
(integer) 5
127.0.0.1:6379> LRANGE mylist 0 -1
1) "v1"
2) "3"
3) "wangyuxing"
4) "insert"
5) "0"
# 向mylist中的insert元素的后面插入insertafter
127.0.0.1:6379> LINSERT mylist after insert insertafter
(integer) 6
127.0.0.1:6379> LRANGE mylist 0 -1
1) "v1"
2) "3"
3) "wangyuxing"
4) "insert"
5) "insertafter"
6) "0"
Set（集合）
集合中的元素是不能重复的
添加元素和查看元素：sadd（添加） smembers（查看元素）
# 添加元素 sadd key名 value [value]
127.0.0.1:6379> SADD myset set1 set2
(integer) 2
# SMEMBERS key名
127.0.0.1:6379> SMEMBERS myset
1) "set2"
2) "set1"
127.0.0.1:6379>
移除元素：srem
# srem key名 移除的元素
127.0.0.1:6379> SREM myset set1
(integer) 1
判断值是否存在集合中：sismember
# 判断元素是否在集合中
# SISMEMBER key名 判断的元素
127.0.0.1:6379> SISMEMBER myset set1
(integer) 1
127.0.0.1:6379> SISMEMBER myset set
(integer) 0
判断集合中的个数：scard
# 判断元素的个数
127.0.0.1:6379> SCARD myset
(integer) 2
随机获取集合的值：srandmember
# 随机获取集合的值 srandmember key名 [获取个数默认1]
127.0.0.1:6379> SMEMBERS myset
1) "set6"
2) "set2"
3) "set1"
4) "set4"
5) "set5"
6) "set7"
7) "set3"
8) "set8"
9) "set9"
127.0.0.1:6379> SRANDMEMBER myset
"set1"
127.0.0.1:6379> SRANDMEMBER myset
"set1"
127.0.0.1:6379> SRANDMEMBER myset
"set7"
127.0.0.1:6379> SRANDMEMBER myset
"set9"
# 可以添加参数获取几个
127.0.0.1:6379> SRANDMEMBER myset 4
1) "set6"
2) "set8"
3) "set1"
4) "set3"
随机移除一个元素：spop
# 随机移除一个元素 spop key名 [移除个数默认1]
127.0.0.1:6379> SMEMBERS myset
1) "set4"
2) "set2"
3) "set6"
4) "set8"
5) "set5"
6) "set1"
7) "set7"
8) "set3"
9) "set9"
127.0.0.1:6379> spop myset
"set1"
127.0.0.1:6379> spop myset
"set8"
127.0.0.1:6379> spop myset 2
1) "set3"
2) "set9"
将指定的元素移动到另一个集合中：smove
# 将指定的元素移动到另一个集合中
127.0.0.1:6379> SADD key a b c d
(integer) 4
127.0.0.1:6379> SMOVE key key1 d
(integer) 1
127.0.0.1:6379> SMEMBERS key1
1) "d"
集合的计算：sdiff(差集) sinter(交集) sunion(并集)
127.0.0.1:6379> sadd key1 a b c d e
(integer) 5
127.0.0.1:6379> sadd key a b f j k l
(integer) 6
# 以 key1 为参照找出不同的
127.0.0.1:6379> SDIFF key1 key
1) "e"
2) "c"
3) "d"
# 交集
127.0.0.1:6379> SINTER key1 key
1) "a"
2) "b"
# 并集
127.0.0.1:6379> SUNION key1 key
1) "j"
2) "k"
3) "f"
4) "d"
5) "b"
6) "a"
7) "e"
8) "l"
9) "c"
Hash(map集合)
类型是：key-map
添加值：hset key名 字段名 值 [字段名 值]
127.0.0.1:6379> HSET myhash name zhansan age 4 sex nan
(integer) 3
127.0.0.1:6379> HGET myhash name
"zhansan"
127.0.0.1:6379> HGET myhash age
"4"
127.0.0.1:6379> HGET myhash sex
"nan"
127.0.0.1:6379> HGETALL myhash
1) "name"
2) "zhansan"
3) "age"
4) "4"
5) "sex"
6) "nan"
127.0.0.1:6379> HMGET myhash name sex
1) "zhansan"
2) "nan"
获取值：hget(单个值) hmget(多个值) hgetall(获取全部的值)
# hget(单个值)
127.0.0.1:6379> HGET myhash name
"zhansan"
127.0.0.1:6379> HGET myhash age
"4"
# hmget(多个值)
127.0.0.1:6379> HMGET myhash name sex
1) "zhansan"
2) "nan"
# hgetall(获取全部的值)
127.0.0.1:6379> HGETALL myhash
1) "name"
2) "zhansan"
3) "age"
4) "4"
5) "sex"
6) "nan"
删除值：hdel
127.0.0.1:6379> HDEL myhash name
(integer) 1
127.0.0.1:6379> HGETALL myhash
1) "age"
2) "4"
3) "sex"
4) "nan"
获取hash长度：hlen
127.0.0.1:6379> hlen myhash
(integer) 2
判断hash中的字段是否存在： hexists
127.0.0.1:6379> HEXISTS myhash name
(integer) 0
127.0.0.1:6379> HEXISTS myhash age
(integer) 1
获取所有字段或所有值：hkeys(获取所有字段) hvals(获取所有value)
127.0.0.1:6379> HKEYS myhash
1) "age"
2) "sex"
127.0.0.1:6379> HVALS myhash
1) "4"
2) "nan"
字段自增：hincrby(自增)
127.0.0.1:6379> HSET myhash num 2
(integer) 1
127.0.0.1:6379> HINCRBY myhash num 4
(integer) 6
127.0.0.1:6379> HGET myhash num
"6"
判断后在添加：hsetnx
# 判断是否存在 不存在才能设置
127.0.0.1:6379> HSETNX myhash num 5
(integer) 0
127.0.0.1:6379> HSETNX myhash num1 1
(integer) 1
设置对象：
# hash更适合存对象
127.0.0.1:6379> HSET user:1 name xiaohong age 18 sex nan
(integer) 3
Zset(有序集合)
在set 的基础添加一个值，set k1 sorce v1
添加值和查看值：zadd(添加) zrange(查看)
# 添加值 zadd key名 序号(排序使用) value
127.0.0.1:6379> ZADD myset 1 one 2 two 3 three
(integer) 3
# 查看值
127.0.0.1:6379> ZRANGE myset 0 -1 # 升序
1) "one"
2) "two"
3) "three"
# 查看值
127.0.0.1:6379> ZREVRANGE myset 0 -1 # 升序
1) "one"
2) "two"
3) "three"
排序的实现（升序）：zrangebyscore 最小值 最大值 [withsorce(是否带上成绩选填)] 取的个数
127.0.0.1:6379> ZADD sorce 70 zhangsan 80 lisi 66 wangwu
(integer) 3
127.0.0.1:6379> ZRANGEBYSCORE sorce -inf +inf
1) "wangwu"
2) "zhangsan"
3) "lisi"
排序的实现（降序）：zrevrangebyscore 最大值 最小值 [withsorce(是否带上成绩选填)] 取的个数
127.0.0.1:6379> ZREVRANGEBYSCORE sorce +inf -inf
1) "lisi"
2) "zhangsan"
3) "wangwu"
移除元素：zrem
127.0.0.1:6379> ZREM sorce lisi wangwu
(integer) 2
127.0.0.1:6379> ZRANGE sorce 0 -1
1) "zhangsan"
获取有序集合的个数：zcard
# zcard key名
127.0.0.1:6379> ZCARD sorce
(integer) 3
统计区间的个数：zcount
127.0.0.1:6379> ZRANGEBYSCORE sorce -inf +inf withscores
1) "wangwu"
2) "66"
3) "zhangsan"
4) "70"
5) "lisi"
6) "80"
# 获取 sorce 区间的s
127.0.0.1:6379> ZCOUNT sorce 70 100
(integer) 2
排行榜实现、带权处理、更多排序的东西
特殊数据类型
geospatia(地理位置)
定位功能 附件的人 打车距离计算 等待有关的距离的信息
测试查询经纬度的位置的网站：拾取坐标系统 (baidu.com)
具体命令使用
添加地理位置：geoadd
# 添加一些地理位置用于测试
# 添加格式为 geoadd key名 经度 维度 名称
127.0.0.1:6379> GEOADD china:city 116.277132 39.9655828 beijing
(integer) 1
127.0.0.1:6379> GEOADD china:city 106.559613 26.616218 guiyan
(integer) 0
127.0.0.1:6379> GEOADD china:city 121.470766 31.235188 shanghai
(integer) 1
127.0.0.1:6379> GEOADD china:city 114.066277 22.550325 shenzhen
(integer) 1
127.0.0.1:6379> GEOADD china:city 106.557287 29.561833 chongqin
(integer) 1
获取城市的经纬度：geopos
# 使用 geopos key名 名称(名称可以传递多个)
127.0.0.1:6379> GEOPOS china:city beijing
1) 1) "116.27713233232498169" #经度
2) "39.96558346694765618" #维度
127.0.0.1:6379> GEOPOS china:city beijing shenzhen
1) 1) "116.27713233232498169"
2) "39.96558346694765618"
2) 1) "114.06627863645553589"
2) "22.55032549190071478"
判断两个位置的直线距离geodist
- m 表示单位为米。
- km 表示单位为千米。
- mi 表示单位为英里。
- ft 表示单位为英尺。
# getdist key名 名称1 名称2 [单位 默认是米]
127.0.0.1:6379> geodist china:city beijing shanghai
"1078155.7397"
127.0.0.1:6379> geodist china:city beijing shanghai km
"1078.1557"
查找周围的其他位置：GEORADIUS
# georadius key名 经度 维度 半径 [单位默认是m] [withdist显示到中间位置的距离] [count x 查询的个数]
127.0.0.1:6379> GEORADIUS china:city 110 30 500 km
1) "chongqin"
127.0.0.1:6379> GEORADIUS china:city 110 30 1000 km
1) "guiyan"
2) "liupanshuishi"
3) "chongqin"
4) "shenzhen"
127.0.0.1:6379> GEORADIUS china:city 110 30 500 km withdist
1) 1) "chongqin"
2) "335.8886"
127.0.0.1:6379> GEORADIUS china:city 110 30 700 km withdist
1) 1) "guiyan"
2) "505.0571"
2) 1) "liupanshuishi"
2) "505.0571"
3) 1) "chongqin"
2) "335.8886"
127.0.0.1:6379> GEORADIUS china:city 110 30 700 km withdist count 2
1) 1) "chongqin"
2) "335.8886"
2) 1) "guiyan"
2) "505.0571"
通过城市的名称查询周围的值：georadiusbymember
# GEORADIUSBYMEMBER key名 中心点 半径 [单位默认是m] [withdist显示到中间位置的距离] [count x 查询的个数]
127.0.0.1:6379> GEORADIUSBYMEMBER china:city shanghai 1500 km withdist count 3
1) 1) "shanghai"
2) "0.0000"
2) 1) "beijing"
2) "1078.1557"
3) 1) "shenzhen"
2) "1212.7005"
geospatia 底层是基于 Zset，我们可以使用zset 的操作来对其进行操作
127.0.0.1:6379> ZRANGE china:city 0 -1 #查看元素
1) "guiyan"
2) "liupanshuishi"
3) "chongqin"
4) "shenzhen"
5) "shanghai"
6) "beijing"
127.0.0.1:6379> ZREM china:city guiyan # 移除元素
(integer) 1
127.0.0.1:6379> ZREM china:city chongqin
(integer) 1
127.0.0.1:6379> ZRANGE china:city 0 -1
1) "liupanshuishi"
2) "shenzhen"
3) "shanghai"
4) "beijing"
Hyperloglog
统计基数：不重复的元素
传统方式使用 set 保存用户 id 然后使用set的集合做统计数量来计数
使用Hyperloglog 做统计
优点：占有内存是固定的，自需要12kb的内存
缺点：计算真确率，只有 0.81%
# 创建元素
127.0.0.1:6379> PFADD mykey a b c d e f g h i j k l
(integer) 1
# 统计数量
127.0.0.1:6379> PFCOUNT mykey
(integer) 12
# 创建元素
127.0.0.1:6379> PFadd mykey1 i j z x c v b e
(integer) 1
# 合并元素（会移除重复的元素）
127.0.0.1:6379> PFMERGE mkykey3 mykey mykey2
OK
# 查看合并后的计数
127.0.0.1:6379> PFCOUNT mkykey3
(integer) 12
Bitmaps
Bitmaps 使用位存储，只要 0、1两个状态，常用于记录两个状态的值
比如：打卡 每天登录状态
优点，非常省内存，1 字节就能存取8个状态
使用命令
# 在对应的字节上添加记录情况
# setbit key名 bit位 记录值[只能是 0,1]
127.0.0.1:6379> SETBIT denglu 1 0
(integer) 0
127.0.0.1:6379> SETBIT denglu 2 1
(integer) 0
127.0.0.1:6379> SETBIT denglu 3 1
(integer) 0
127.0.0.1:6379> SETBIT denglu 4 0
(integer) 0
127.0.0.1:6379> SETBIT denglu 5 1
(integer) 0
127.0.0.1:6379> SETBIT denglu 6 0
(integer) 0
127.0.0.1:6379> SETBIT denglu 7 1
(integer) 0
# 获取相应位上的值 getbit key名 bit位
127.0.0.1:6379> GETBIT denglu 6
(integer) 0
127.0.0.1:6379> GETBIT denglu 3
(integer) 1
# 统计全部记录为 1 的所有值 [开始字节] [结束字节]
127.0.0.1:6379> BITCOUNT denglu
(integer) 4
# 注意字节于bit的关系 一个字节的8 bit
# 上面统计的数存放在 0~7bit为 所以只能在 0 号上面查找到
127.0.0.1:6379> BITCOUNT denglu 4 7
(integer) 0
127.0.0.1:6379> BITCOUNT denglu 0 1
(integer) 4
事务
Redis单条命令保证原子性，但是事务不保证原子性
Redis事务：
- 开启事务（multi）
- 命令入队（正常命令）
- 执行事务（exec）
具体命令
# 开启事务
127.0.0.1:6379> MULTI
OK
# 事务入队
127.0.0.1:6379(TX)> set k1 v1
QUEUED
127.0.0.1:6379(TX)> set k2 v2
QUEUED
127.0.0.1:6379(TX)> get k2
QUEUED
127.0.0.1:6379(TX)> set k3 v3
QUEUED
127.0.0.1:6379(TX)> get k3
QUEUED
# 执行事务
127.0.0.1:6379(TX)> exec
1) OK
2) OK
3) "v2"
4) OK
5) "v3"
放弃事务 discard
# 开启事务
127.0.0.1:6379> MULTI
OK
127.0.0.1:6379(TX)> set k1 v1
QUEUED
127.0.0.1:6379(TX)> set k2 v2
QUEUED
# 放弃事务
127.0.0.1:6379(TX)> DISCARD
OK
# 因为是放弃事务，所以拿不到值
127.0.0.1:6379> get k1
(nil)
事务出错
编译型错误运行时错误
编译型错误：编译时就出错，所有事务都不执行
运行时错误：只是出错的不执行，其它正常执行
# 编译型错误
127.0.0.1:6379> MULTI # 开启事务
OK
127.0.0.1:6379(TX)> set k1 v1
QUEUED
127.0.0.1:6379(TX)> getset k1 #事务命令已经报错
(error) ERR wrong number of arguments for 'getset' command
127.0.0.1:6379(TX)> set k2 v2
QUEUED
127.0.0.1:6379(TX)> exec # 执行事务
(error) EXECABORT Transaction discarded because of previous errors.
127.0.0.1:6379> get k1 # 获取不到值事务没有执行
(nil)
# 运行时错误
127.0.0.1:6379> MULTI # 开启事务
OK
127.0.0.1:6379(TX)> set k1 v1
QUEUED
127.0.0.1:6379(TX)> set k2 v2 k3 v3 # 错误命令，编译能过，执行会出错
QUEUED
127.0.0.1:6379(TX)> set k4 v4
QUEUED
127.0.0.1:6379(TX)> get k2
QUEUED
127.0.0.1:6379(TX)> get k4
QUEUED
127.0.0.1:6379(TX)> exec #执行事务
1) OK
2) (error) ERR syntax error #命令错误提示
3) OK
4) (nil) # 错误命令没有执行，所有拿不到值
5) "v4" # 正常获取 k4 证明其他正常执行
Redis 的乐观锁
Redis 自带监控 key 的功能，可以用于实现乐观锁
监控 watch
# 正常执行
127.0.0.1:6379> set num 10
OK
127.0.0.1:6379> WATCH num
OK
127.0.0.1:6379> MULTI
OK
127.0.0.1:6379(TX)> INCRBY num 2
QUEUED
127.0.0.1:6379(TX)> INCRBY num 4
QUEUED
127.0.0.1:6379(TX)> exec #事务执行成功监控会自动取消
1) (integer) 12
2) (integer) 16
# 错误执行
127.0.0.1:6379> WATCH num
OK
127.0.0.1:6379> MULTI
OK
127.0.0.1:6379(TX)> DECRBY num 10
QUEUED
# 现在不先执行事务，多开一个客户端模拟多线程插队，修改值
127.0.0.1:6379> get num
"16"
127.0.0.1:6379> set num 10
OK
# 在返回原客户端执行事务
127.0.0.1:6379(TX)> exec #执行任务为 nil 修改失败
(nil)
unwatch 取消监控
切记如果事务执行失败 需要手动的取消监控
127.0.0.1:6379> UNWATCH
OK
Jedis
什么是 Jedis
Java 操作 redis 的操作工具
1、创建一个空的 maven 项目
2、导入依赖
<!-- https://mvnrepository.com/artifact/redis.clients/jedis -->
<dependency>
<groupId>redis.clients</groupId>
<artifactId>jedis</artifactId>
<version>3.6.0</version>
</dependency>
3、测试
对数据库的操作
package com.wyx;
import redis.clients.jedis.Jedis;
public class JedisTest {
public static void main(String[] args) {
// 连接url 和 端口号
System.out.println("################ 数据库操作 ####################");
Jedis jedis = new Jedis("192.168.137.129",6379);
System.out.println("测试连接："+jedis.ping());
System.out.println("选择数据库 2号："+jedis.select(2));
System.out.println("清空 2号数据库："+jedis.flushDB());
System.out.println("查看 2号数据库的所有："+ jedis.keys("*"));
System.out.println("清空所有数据库："+ jedis.flushAll());
System.out.println("选择 0号数据库："+jedis.select(0));
System.out.println("向数据库添加key为name值为zhang sang的key：" + jedis.set("name", "zhang sang"));
System.out.println("获取数据库的key为name的值："+ jedis.get("name"));
System.out.println("判断数据库中的key为name的key是否存在：" + jedis.exists("name"));
System.out.println("判断数据库中的key为age的key是否存在：" + jedis.exists("age"));
System.out.println("查看数据库大小："+jedis.dbSize());
System.out.println("将key为name的key 移动到 2号数据库："+ jedis.move("name", 2));
System.out.println("选择 2号数据库："+ jedis.select(2));
System.out.println("判断 key属于什么类型："+jedis.type("name"));
System.out.println("设置key 在10秒后过期："+jedis.expire("name",4));
//如果ttl 等于 -2 代表已经过期
for (int i = -2; i != jedis.ttl("name");) {
System.out.println("name的 key 将在"+jedis.ttl("name")+"秒后过期");
try {
// 睡眠1秒
Thread.sleep(1000);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
System.out.println("再次获取 name 的值："+jedis.get("name"));
System.out.println("查看数据库大小："+jedis.dbSize());
}
}
测试结果：
测试连接：PONG
选择数据库 2号：OK
清空 2号数据库：OK
查看 2号数据库的所有：[]
清空所有数据库：OK
选择 0号数据库：OK
向数据库添加key为name值为zhang sang的key：OK
获取数据库的key为name的值：zhang sang
判断数据库中的key为name的key是否存在：true
判断数据库中的key为age的key是否存在：false
查看数据库大小：1
将key为name的key 移动到 2号数据库：1
选择 2号数据库：OK
判断 key属于什么类型：string
设置key 在10秒后过期：1
name的 key 将在4秒后过期
name的 key 将在3秒后过期
name的 key 将在2秒后过期
name的 key 将在1秒后过期
再次获取 name 的值：null
查看数据库大小：0
String类型操作
package com.wyx;
import redis.clients.jedis.Jedis;
public class JedisTest {
public static void main(String[] args) {
// 连接url 和 端口号
System.out.println("################ string操作 ####################");
Jedis jedis = new Jedis("192.168.137.129",6379);
jedis.flushDB();
System.out.println("测试连接："+jedis.ping());
System.out.println("设置一个key为hello的 key："+ jedis.set("hello", "hello"));
System.out.println("输出key为 hello 的值："+jedis.get("hello"));
System.out.println("给key为 hello 的key 追加字符串："+jedis.append("hello"," this is a redis"));
System.out.println("查看 hello 的字符串长度："+ jedis.strlen("hello"));
System.out.println("按下标获取字符串(获取0~9)："+ jedis.getrange("hello",0,9));
System.out.println("按下标获取字符串(获取0~-1)全部："+ jedis.getrange("hello",0,-1));
System.out.println("从第 6 个位置用字符串替换："+jedis.setrange("hello",6,"xxxxx"));
System.out.println("输出key为 hello 的值："+jedis.get("hello"));
System.out.println("设置 key为name的值并给出过期时间为 5 秒："+ jedis.setex("name",5,"li si"));
System.out.println("判断没有hello的键才能设置成功："+jedis.setnx("hello","ll"));
System.out.println("判断没有age的键才能设置成功："+jedis.setnx("age","18"));
System.out.println("添加一个key为 num 值为数字的 key："+ jedis.set("num","10"));
System.out.println("获取 num 的值："+jedis.get("num"));
System.out.println("num 值加一 ："+jedis.incr("num"));
System.out.println("获取 num 的值："+jedis.get("num"));
System.out.println("num 值加 10 ："+jedis.incrBy("num",10));
System.out.println("获取 num 的值："+jedis.get("num"));
System.out.println("num 值减一 ："+jedis.decr("num"));
System.out.println("获取 num 的值："+jedis.get("num"));
System.out.println("num 值减 5 ："+jedis.decrBy("num",5));
System.out.println("获取 num 的值："+jedis.get("num"));
System.out.println("###################################");
System.out.println("更多操作查看 string 的redis 命令");
}
}
测试结果：
################ string操作 ####################
测试连接：PONG
设置一个key为hello的 key：OK
输出key为 hello 的值：hello
给key为 hello 的key 追加字符串：21
查看 hello 的字符串长度：21
按下标获取字符串(获取0~9)：hello this
按下标获取字符串(获取0~-1)全部：hello this is a redis
从第 6 个位置用字符串替换：21
输出key为 hello 的值：hello xxxxxis a redis
设置 key为name的值并给出过期时间为 5 秒：OK
判断没有hello的键才能设置成功：0
判断没有age的键才能设置成功：1
添加一个key为 num 值为数字的 key：OK
获取 num 的值：10
num 值加一 ：11
获取 num 的值：11
num 值加 10 ：21
获取 num 的值：21
num 值减一 ：20
获取 num 的值：20
num 值减 5 ：15
获取 num 的值：15
###################################
更多操作查看 string 的redis 命令
其他
剩下还有很多对 List、Set、Hash、Zset、gepspatia、Hyperloglog、Bitmaps、的操作和命令差不多，具体使用时对应修改即可。
整合SpringBoot
简单使用
1、创建SpringBoot项目
2、导入以下依赖
<!--SpringBoot集成的Redis启动依赖-->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-redis</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<!--lombok依赖-->
<dependency>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
<optional>true</optional>
</dependency>
3、配置连接
spring.redis.host=192.168.137.129
spring.redis.port=6379
4、编码测试
package com.wyx;
import org.junit.jupiter.api.Test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.data.redis.core.RedisTemplate;
@SpringBootTest
class SpringBootRedisApplicationTests {
// 注入Redis操作模板
@Autowired
RedisTemplate redisTemplate;
@Test
void contextLoads() {
// 设置一个 key
redisTemplate.opsForValue().set("name","Wang Yu Xing");
// 获取一个key
System.out.println(redisTemplate.opsForValue().get("name"));
}
}
5、测试结果
源码解析
根据对 Springboot 的学习，我们自需要找到 spring-boot-autoconfigure-2.4.5.jar 下的 META-INF下的spring.factories 查看有关 redis的自动配置，如下。
打开图片中勾选的类，查看如下。
查看：RedisProperties类，查看其中的我们该如何配置
/* 以下是在连接 Redis 是我们可以配置的属性
配置格式只需要在 全局配置文件 application.properties 下配置即可，
例如在简单案例中我们配置的
spring.redis.host=192.168.137.129
spring.redis.port=6379
表示需要连接的主机和对应的端口号。
*/
@ConfigurationProperties(prefix = "spring.redis")
public class RedisProperties {
/**
* Database index used by the connection factory.
*/
private int database = 0;
/**
* Connection URL. Overrides host, port, and password. User is ignored. Example:
* redis://user:password@example.com:6379
*/
private String url;
/**
* Redis server host.
*/
private String host = "localhost";
/**
* Login username of the redis server.
*/
private String username;
/**
* Login password of the redis server.
*/
private String password;
/**
* Redis server port.
*/
private int port = 6379;
/**
* Whether to enable SSL support.
*/
private boolean ssl;
/**
* Read timeout.
*/
private Duration timeout;
/**
* Connection timeout.
*/
private Duration connectTimeout;
/**
* Client name to be set on connections with CLIENT SETNAME.
*/
private String clientName;
/**
* Type of client to use. By default, auto-detected according to the classpath.
*/
private ClientType clientType;
private Sentinel sentinel;
private Cluster cluster;
查看：默认配置的 redisTemplate
public class RedisAutoConfiguration {
@Bean
@ConditionalOnMissingBean(name = "redisTemplate")
@ConditionalOnSingleCandidate(RedisConnectionFactory.class)
public RedisTemplate<Object, Object> redisTemplate(RedisConnectionFactory redisConnectionFactory) {
// 默认配置的 RedisTemplate 并没有给我们序列化（网络传输保证格式），而且几乎没有配置，所以一般情况下，我们并不会使用默认配置的模板，我们会自定义模板将其覆盖掉。
RedisTemplate<Object, Object> template = new RedisTemplate<>();
template.setConnectionFactory(redisConnectionFactory);
return template;
}
}
由于默认配置的模板，所以在使用时如果没有序列化会报错如下：
package com.wyx.pojo;
import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;
@Data
@NoArgsConstructor
@AllArgsConstructor
public class User {
private String name;
private Integer age;
private String sex;
}
package com.wyx;
import com.wyx.pojo.User;
import org.junit.jupiter.api.Test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.data.redis.core.RedisTemplate;
@SpringBootTest
class SpringBootRedisApplicationTests {
@Autowired
RedisTemplate redisTemplate;
@Test
void contextLoads() {
User user = new User("张明", 18, "男");
// 设置一个 key
redisTemplate.opsForValue().set("user",user);
// 获取一个key
System.out.println(redisTemplate.opsForValue().get("user"));
}
}
运行测试：没有序列化，所以一般情况下，我们要重写模板
自定义 RedisTemplate
package com.wyx.conf;
import com.fasterxml.jackson.annotation.JsonAutoDetect;
import com.fasterxml.jackson.annotation.PropertyAccessor;
import com.fasterxml.jackson.databind.ObjectMapper;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.data.redis.connection.RedisConnectionFactory;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.data.redis.serializer.Jackson2JsonRedisSerializer;
import org.springframework.data.redis.serializer.StringRedisSerializer;
@Configuration
public class RedisConfig {
@Bean
RedisTemplate<String,Object> redisTemplate(RedisConnectionFactory factory){
RedisTemplate<String, Object> template = new RedisTemplate();
template.setConnectionFactory(factory);
Jackson2JsonRedisSerializer jackson2JsonRedisSerializer = new Jackson2JsonRedisSerializer(Object.class);
ObjectMapper om = new ObjectMapper();
om.setVisibility(PropertyAccessor.ALL, JsonAutoDetect.Visibility.ANY);
om.enableDefaultTyping(ObjectMapper.DefaultTyping.NON_FINAL);
jackson2JsonRedisSerializer.setObjectMapper(om);
StringRedisSerializer stringRedisSerializer = new StringRedisSerializer();
// key采用String的序列化方式
template.setKeySerializer(stringRedisSerializer);
// hash的key也采用String的序列化方式
template.setHashKeySerializer(stringRedisSerializer);
// value序列化方式采用jackson
template.setValueSerializer(jackson2JsonRedisSerializer);
// hash的value序列化方式采用jackson
template.setHashValueSerializer(jackson2JsonRedisSerializer);
template.afterPropertiesSet();
return template;
}
}
封装 redisTemplate 的操作
package com.wyx.utils;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.stereotype.Component;
import org.springframework.util.CollectionUtils;
import javax.annotation.Resource;
import java.util.Collection;
import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.concurrent.TimeUnit;
@Component
@SuppressWarnings("all")
public class RedisUtil {
@Resource
private RedisTemplate<String, Object> redisTemplate;
/**
* 指定缓存失效时间
*
* @param key 键
* @param time 时间(秒)
* @return boolean 返回布尔值
*/
public boolean expire(String key, long time) {
try {
if (time > 0) {
redisTemplate.expire(key, time, TimeUnit.SECONDS);
}
return true;
} catch (Exception e) {
e.printStackTrace();
return false;
}
}
/**
* 根据key 获取过期时间
*
* @param key 键 不能为null
* @return 时间(秒) 返回-1代表为永久有效
*/
public long getExpire(String key) {
return redisTemplate.getExpire(key, TimeUnit.SECONDS);
}
/**
* 判断key是否存在
*
* @param key 键
* @return true 存在 false不存在
*/
public boolean hasKey(String key) {
try {
return redisTemplate.hasKey(key);
} catch (Exception e) {
e.printStackTrace();
return false;
}
}
/**
* 删除缓存
*
* @param key 可以传一个值 或多个
*/
public void del(String... key) {
if (key != null && key.length > 0) {
if (key.length == 1) {
redisTemplate.delete(key[0]);
} else {
redisTemplate.delete((Collection<String>) CollectionUtils.arrayToList(key));
}
}
}
/**
* 普通缓存获取
*
* @param key 键
* @return 值
*/
public Object get(String key) {
return key == null ? null : redisTemplate.opsForValue().get(key);
}
/**
* 普通缓存放入
*
* @param key 键
* @param value 值
* @return true成功 false失败
*/
public boolean set(String key, Object value) {
try {
redisTemplate.opsForValue().set(key, value);
return true;
} catch (Exception e) {
e.printStackTrace();
return false;
}
}
/**
* 普通缓存放入并设置时间
*
* @param key 键
* @param value 值
* @param time 时间(秒) time要大于0 如果time小于等于0 将设置无限期
* @return true成功 false 失败
*/
public boolean set(String key, Object value, long time) {
try {
if (time > 0) {
redisTemplate.opsForValue().set(key, value, time, TimeUnit.SECONDS);
} else {
set(key, value);
}
return true;
} catch (Exception e) {
e.printStackTrace();
return false;
}
}
/**
* 递增
*
* @param key 键
* @param delta 要增加几(大于0)
* @return
*/
public long incr(String key, long delta) {
if (delta < 0) {
throw new RuntimeException("递增因子必须大于0");
}
return redisTemplate.opsForValue().increment(key, delta);
}
/**
* 递减
*
* @param key 键
* @param delta 要减少几(小于0)
* @return
*/
public long decr(String key, long delta) {
if (delta < 0) {
throw new RuntimeException("递减因子必须大于0");
}
return redisTemplate.opsForValue().increment(key, -delta);
}
// ================================Map=================================
/**
* HashGet
*
* @param key 键 不能为null
* @param item 项 不能为null
* @return 值
*/
public Object hget(String key, String item) {
return redisTemplate.opsForHash().get(key, item);
}
/**
* 获取hashKey对应的所有键值
*
* @param key 键
* @return 对应的多个键值
*/
public Map<Object, Object> hmget(String key) {
return redisTemplate.opsForHash().entries(key);
}
/**
* HashSet
*
* @param key 键
* @param map 对应多个键值
* @return true 成功 false 失败
*/
public boolean hmset(String key, Map<String, Object> map) {
try {
redisTemplate.opsForHash().putAll(key, map);
return true;
} catch (Exception e) {
e.printStackTrace();
return false;
}
}
/**
* HashSet 并设置时间
*
* @param key 键
* @param map 对应多个键值
* @param time 时间(秒)
* @return true成功 false失败
*/
public boolean hmset(String key, Map<String, Object> map, long time) {
try {
redisTemplate.opsForHash().putAll(key, map);
if (time > 0) {
expire(key, time);
}
return true;
} catch (Exception e) {
e.printStackTrace();
return false;
}
}
/**
* 向一张hash表中放入数据,如果不存在将创建
*
* @param key 键
* @param item 项
* @param value 值
* @return true 成功 false失败
*/
public boolean hset(String key, String item, Object value) {
try {
redisTemplate.opsForHash().put(key, item, value);
return true;
} catch (Exception e) {
e.printStackTrace();
return false;
}
}
/**
* 向一张hash表中放入数据,如果不存在将创建
*
* @param key 键
* @param item 项
* @param value 值
* @param time 时间(秒) 注意:如果已存在的hash表有时间,这里将会替换原有的时间
* @return true 成功 false失败
*/
public boolean hset(String key, String item, Object value, long time) {
try {
redisTemplate.opsForHash().put(key, item, value);
if (time > 0) {
expire(key, time);
}
return true;
} catch (Exception e) {
e.printStackTrace();
return false;
}
}
/**
* 删除hash表中的值
*
* @param key 键 不能为null
* @param item 项 可以使多个 不能为null
*/
public void hdel(String key, Object... item) {
redisTemplate.opsForHash().delete(key, item);
}
/**
* 判断hash表中是否有该项的值
*
* @param key 键 不能为null
* @param item 项 不能为null
* @return true 存在 false不存在
*/
public boolean hHasKey(String key, String item) {
return redisTemplate.opsForHash().hasKey(key, item);
}
/**
* hash递增 如果不存在,就会创建一个 并把新增后的值返回
*
* @param key 键
* @param item 项
* @param by 要增加几(大于0)
* @return
*/
public double hincr(String key, String item, double by) {
return redisTemplate.opsForHash().increment(key, item, by);
}
/**
* hash递减
*
* @param key 键
* @param item 项
* @param by 要减少记(小于0)
* @return
*/
public double hdecr(String key, String item, double by) {
return redisTemplate.opsForHash().increment(key, item, -by);
}
// ============================set=============================
/**
* 根据key获取Set中的所有值
*
* @param key 键
* @return
*/
public Set<Object> sGet(String key) {
try {
return redisTemplate.opsForSet().members(key);
} catch (Exception e) {
e.printStackTrace();
return null;
}
}
/**
* 根据value从一个set中查询,是否存在
*
* @param key 键
* @param value 值
* @return true 存在 false不存在
*/
public boolean sHasKey(String key, Object value) {
try {
return redisTemplate.opsForSet().isMember(key, value);
} catch (Exception e) {
e.printStackTrace();
return false;
}
}
/**
* 将数据放入set缓存
*
* @param key 键
* @param values 值 可以是多个
* @return 成功个数
*/
public long sSet(String key, Object... values) {
try {
return redisTemplate.opsForSet().add(key, values);
} catch (Exception e) {
e.printStackTrace();
return 0;
}
}
/**
* 将set数据放入缓存
*
* @param key 键
* @param time 时间(秒)
* @param values 值 可以是多个
* @return 成功个数
*/
public long sSetAndTime(String key, long time, Object... values) {
try {
Long count = redisTemplate.opsForSet().add(key, values);
if (time > 0)
expire(key, time);
return count;
} catch (Exception e) {
e.printStackTrace();
return 0;
}
}
/**
* 获取set缓存的长度
*
* @param key 键
* @return
*/
public long sGetSetSize(String key) {
try {
return redisTemplate.opsForSet().size(key);
} catch (Exception e) {
e.printStackTrace();
return 0;
}
}
/**
* 移除值为value的
*
* @param key 键
* @param values 值 可以是多个
* @return 移除的个数
*/
public long setRemove(String key, Object... values) {
try {
Long count = redisTemplate.opsForSet().remove(key, values);
return count;
} catch (Exception e) {
e.printStackTrace();
return 0;
}
}
// ===============================list=================================
/**
* 获取list缓存的内容
*
* @param key 键
* @param start 开始
* @param end 结束 0 到 -1代表所有值
* @return
*/
public List<Object> lGet(String key, long start, long end) {
try {
return redisTemplate.opsForList().range(key, start, end);
} catch (Exception e) {
e.printStackTrace();
return null;
}
}
/**
* 获取list缓存的长度
*
* @param key 键
* @return
*/
public long lGetListSize(String key) {
try {
return redisTemplate.opsForList().size(key);
} catch (Exception e) {
e.printStackTrace();
return 0;
}
}
/**
* 通过索引 获取list中的值
*
* @param key 键
* @param index 索引 index>0时， 0 表头，1 第二个元素，依次类推；index<0时，-1，表尾，-2倒数第二个元素，依次类推
* @return
*/
public Object lGetIndex(String key, long index) {
try {
return redisTemplate.opsForList().index(key, index);
} catch (Exception e) {
e.printStackTrace();
return null;
}
}
/**
* 将list放入缓存
*
* @param key 键
* @param value 值
* @return
*/
public boolean lSet(String key, Object value) {
try {
redisTemplate.opsForList().rightPush(key, value);
return true;
} catch (Exception e) {
e.printStackTrace();
return false;
}
}
/**
* 将list放入缓存
*
* @param key 键
* @param value 值
* @param time 时间(秒)
* @return
*/
public boolean lSet(String key, Object value, long time) {
try {
redisTemplate.opsForList().rightPush(key, value);
if (time > 0)
expire(key, time);
return true;
} catch (Exception e) {
e.printStackTrace();
return false;
}
}
/**
* 将list放入缓存
*
* @param key 键
* @param value 值
* @return
*/
public boolean lSet(String key, List<Object> value) {
try {
redisTemplate.opsForList().rightPushAll(key, value);
return true;
} catch (Exception e) {
e.printStackTrace();
return false;
}
}
/**
* 将list放入缓存
*
* @param key 键
* @param value 值
* @param time 时间(秒)
* @return
*/
public boolean lSet(String key, List<Object> value, long time) {
try {
redisTemplate.opsForList().rightPushAll(key, value);
if (time > 0)
expire(key, time);
return true;
} catch (Exception e) {
e.printStackTrace();
return false;
}
}
/**
* 根据索引修改list中的某条数据
*
* @param key 键
* @param index 索引
* @param value 值
* @return
*/
public boolean lUpdateIndex(String key, long index, Object value) {
try {
redisTemplate.opsForList().set(key, index, value);
return true;
} catch (Exception e) {
e.printStackTrace();
return false;
}
}
/**
* 移除N个值为value
*
* @param key 键
* @param count 移除多少个
* @param value 值
* @return 移除的个数
*/
public long lRemove(String key, long count, Object value) {
try {
Long remove = redisTemplate.opsForList().remove(key, count, value);
return remove;
} catch (Exception e) {
e.printStackTrace();
return 0;
}
}
}
Redis 配置文件
# Redis configuration file example.
# Redis 配置文件示例。
#
# Note that in order to read the configuration file, Redis must be
# started with the file path as first argument:
# 注意，为了读取配置文件，Redis必须是以文件路径作为第一个参数开头：
# 启动的配置文件必须包含目录，如下：
# ./redis-server /path/to/redis.conf
# Note on units: when memory size is needed, it is possible to specify
# it in the usual form of 1k 5GB 4M and so forth:
# 关于单位的注释：需要内存大小时，可以指定，通常的1k 5GB 4M格式，依此类推：
#
# 1k => 1000 bytes
# 1kb => 1024 bytes
# 1m => 1000000 bytes
# 1mb => 1024*1024 bytes
# 1g => 1000000000 bytes
# 1gb => 1024*1024*1024 bytes
#
# units are case insensitive so 1GB 1Gb 1gB are all the same.
# 单位不区分大小写，因此1GB 1Gb 1gB都相同。
################################## INCLUDES ###################################
# Include one or more other config files here. This is useful if you
# have a standard template that goes to all Redis servers but also need
# to customize a few per-server settings. Include files can include
# other files, so use this wisely.
#
# Note that option "include" won't be rewritten by command "CONFIG REWRITE"
# from admin or Redis Sentinel. Since Redis always uses the last processed
# line as value of a configuration directive, you'd better put includes
# at the beginning of this file to avoid overwriting config change at runtime.
#
# If instead you are interested in using includes to override configuration
# options, it is better to use include as the last line.
#
# 导入其他的配置文件，组成同一个
# include /path/to/local.conf
# include /path/to/other.conf
################################## MODULES #####################################
# Load modules at startup. If the server is not able to load modules
# it will abort. It is possible to use multiple loadmodule directives.
# 在启动时加载模块。 如果服务器无法加载模块，它会中止。 可以使用多个loadmodule指令。
#
# loadmodule /path/to/my_module.so
# loadmodule /path/to/other_module.so
################################## NETWORK #####################################
# By default, if no "bind" configuration directive is specified, Redis listens
# for connections from all available network interfaces on the host machine.
# It is possible to listen to just one or multiple selected interfaces using
# the "bind" configuration directive, followed by one or more IP addresses.
# Each address can be prefixed by "-", which means that redis will not fail to
# start if the address is not available. Being not available only refers to
# addresses that does not correspond to any network interfece. Addresses that
# are already in use will always fail, and unsupported protocols will always BE
# silently skipped.
#
# Examples:
#
# bind 192.168.1.100 10.0.0.1 # listens on two specific IPv4 addresses
# bind 127.0.0.1 ::1 # listens on loopback IPv4 and IPv6
# bind * -::* # like the default, all available interfaces
#
# ~~~ WARNING ~~~ If the computer running Redis is directly exposed to the
# internet, binding to all the interfaces is dangerous and will expose the
# instance to everybody on the internet. So by default we uncomment the
# following bind directive, that will force Redis to listen only on the
# IPv4 and IPv6 (if available) loopback interface addresses (this means Redis
# will only be able to accept client connections from the same host that it is
# running on).
#
# IF YOU ARE SURE YOU WANT YOUR INSTANCE TO LISTEN TO ALL THE INTERFACES
# JUST COMMENT OUT THE FOLLOWING LINE.
# ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
# 绑定的Ip，如果不绑定在不能访问，具体配置参考上面
# 如果是使用服务器配置，那么这个是必须的
bind 127.0.0.1 -::1
# Protected mode is a layer of security protection, in order to avoid that
# Redis instances left open on the internet are accessed and exploited.
#
# When protected mode is on and if:
#
# 1) The server is not binding explicitly to a set of addresses using the
# "bind" directive.
# 2) No password is configured.
#
# The server only accepts connections from clients connecting from the
# IPv4 and IPv6 loopback addresses 127.0.0.1 and ::1, and from Unix domain
# sockets.
#
# By default protected mode is enabled. You should disable it only if
# you are sure you want clients from other hosts to connect to Redis
# even if no authentication is configured, nor a specific set of interfaces
# are explicitly listed using the "bind" directive.
# 默认受保护模式是开启的，如果你关闭了，使用其他的客户端连接，都可以连接，如果开启了，具体查看 bind 中绑定的IP和规则，绑定了才能访问。
# 是否用受保护模式启动
protected-mode yes
# Accept connections on the specified port, default is 6379 (IANA #815344).
# If port 0 is specified Redis will not listen on a TCP socket.
# 接收连接的端口，默认也是服务启动的端口
port 6379
# TCP listen() backlog.
#
# In high requests-per-second environments you need a high backlog in order
# to avoid slow clients connection issues. Note that the Linux kernel
# will silently truncate it to the value of /proc/sys/net/core/somaxconn so
# make sure to raise both the value of somaxconn and tcp_max_syn_backlog
# in order to get the desired effect.
# 设置tcp的backlog,backlog其实是一个连接队列,backlog队列总和=未完成三次握手队列+已完成三次握手队列.
# 在高并发环境下你需要一个高的backlog值来避免慢客户端连接问题.
# 注意linux内核会将这个值减小到/proc/sys/net/core/somaxconn的值,所以需要确认增大somaxconn和tcp_max_syn_backlog两个值来达到想要的效果
# 更改客户端连接的速度，值越大越快
# tcp-backlog 511
# Unix socket.
#
# Specify the path for the Unix socket that will be used to listen for
# incoming connections. There is no default, so Redis will not listen
# on a unix socket when not specified.
#
# unixsocket /run/redis.sock
# unixsocketperm 700
# Close the connection after a client is idle for N seconds (0 to disable)
# 连接超时的时间设置，如果是0则不设置超时时间
timeout 0
# TCP keepalive.
#
# If non-zero, use SO_KEEPALIVE to send TCP ACKs to clients in absence
# of communication. This is useful for two reasons:
#
# 1) Detect dead peers.
# 2) Force network equipment in the middle to consider the connection to be
# alive.
#
# On Linux, the specified value (in seconds) is the period used to send ACKs.
# Note that to close the connection the double of the time is needed.
# On other kernels the period depends on the kernel configuration.
#
# A reasonable value for this option is 300 seconds, which is the new
# Redis default starting with Redis 3.2.1.
# 保持连接的超时时间，单位为秒,如果设置为0,则不会进行keepalive检测
tcp-keepalive 300
################################# TLS/SSL #####################################
# By default, TLS/SSL is disabled. To enable it, the "tls-port" configuration
# directive can be used to define TLS-listening ports. To enable TLS on the
# default port, use:
#
# port 0
# tls-port 6379
# Configure a X.509 certificate and private key to use for authenticating the
# server to connected clients, masters or cluster peers. These files should be
# PEM formatted.
#
# tls-cert-file redis.crt
# tls-key-file redis.key
#
# If the key file is encrypted using a passphrase, it can be included here
# as well.
#
# tls-key-file-pass secret
# Normally Redis uses the same certificate for both server functions (accepting
# connections) and client functions (replicating from a master, establishing
# cluster bus connections, etc.).
#
# Sometimes certificates are issued with attributes that designate them as
# client-only or server-only certificates. In that case it may be desired to use
# different certificates for incoming (server) and outgoing (client)
# connections. To do that, use the following directives:
#
# tls-client-cert-file client.crt
# tls-client-key-file client.key
#
# If the key file is encrypted using a passphrase, it can be included here
# as well.
#
# tls-client-key-file-pass secret
# Configure a DH parameters file to enable Diffie-Hellman (DH) key exchange:
#
# tls-dh-params-file redis.dh
# Configure a CA certificate(s) bundle or directory to authenticate TLS/SSL
# clients and peers. Redis requires an explicit configuration of at least one
# of these, and will not implicitly use the system wide configuration.
#
# tls-ca-cert-file ca.crt
# tls-ca-cert-dir /etc/ssl/certs
# By default, clients (including replica servers) on a TLS port are required
# to authenticate using valid client side certificates.
#
# If "no" is specified, client certificates are not required and not accepted.
# If "optional" is specified, client certificates are accepted and must be
# valid if provided, but are not required.
#
# tls-auth-clients no
# tls-auth-clients optional
# By default, a Redis replica does not attempt to establish a TLS connection
# with its master.
#
# Use the following directive to enable TLS on replication links.
#
# tls-replication yes
# By default, the Redis Cluster bus uses a plain TCP connection. To enable
# TLS for the bus protocol, use the following directive:
#
# tls-cluster yes
# By default, only TLSv1.2 and TLSv1.3 are enabled and it is highly recommended
# that older formally deprecated versions are kept disabled to reduce the attack surface.
# You can explicitly specify TLS versions to support.
# Allowed values are case insensitive and include "TLSv1", "TLSv1.1", "TLSv1.2",
# "TLSv1.3" (OpenSSL >= 1.1.1) or any combination.
# To enable only TLSv1.2 and TLSv1.3, use:
#
# tls-protocols "TLSv1.2 TLSv1.3"
# Configure allowed ciphers. See the ciphers(1ssl) manpage for more information
# about the syntax of this string.
#
# Note: this configuration applies only to <= TLSv1.2.
#
# tls-ciphers DEFAULT:!MEDIUM
# Configure allowed TLSv1.3 ciphersuites. See the ciphers(1ssl) manpage for more
# information about the syntax of this string, and specifically for TLSv1.3
# ciphersuites.
#
# tls-ciphersuites TLS_CHACHA20_POLY1305_SHA256
# When choosing a cipher, use the server's preference instead of the client
# preference. By default, the server follows the client's preference.
#
# tls-prefer-server-ciphers yes
# By default, TLS session caching is enabled to allow faster and less expensive
# reconnections by clients that support it. Use the following directive to disable
# caching.
#
# tls-session-caching no
# Change the default number of TLS sessions cached. A zero value sets the cache
# to unlimited size. The default size is 20480.
#
# tls-session-cache-size 5000
# Change the default timeout of cached TLS sessions. The default timeout is 300
# seconds.
#
# tls-session-cache-timeout 60
################################# GENERAL #####################################
# By default Redis does not run as a daemon. Use 'yes' if you need it.
# Note that Redis will write a pid file in /var/run/redis.pid when daemonized.
# When Redis is supervised by upstart or systemd, this parameter has no impact.
# 是否用后台方式启动，默认为no
daemonize yes
# If you run Redis from upstart or systemd, Redis can interact with your
# supervision tree. Options:
# supervised no - no supervision interaction
# supervised upstart - signal upstart by putting Redis into SIGSTOP mode
# requires "expect stop" in your upstart job config
# supervised systemd - signal systemd by writing READY=1 to $NOTIFY_SOCKET
# on startup, and updating Redis status on a regular
# basis.
# supervised auto - detect upstart or systemd method based on
# UPSTART_JOB or NOTIFY_SOCKET environment variables
# Note: these supervision methods only signal "process is ready."
# They do not enable continuous pings back to your supervisor.
#
# The default is "no". To run under upstart/systemd, you can simply uncomment
# the line below:
#
# 管理守护进程
# supervised auto
# If a pid file is specified, Redis writes it where specified at startup
# and removes it at exit.
#
# When the server runs non daemonized, no pid file is created if none is
# specified in the configuration. When the server is daemonized, the pid file
# is used even if not specified, defaulting to "/var/run/redis.pid".
#
# Creating a pid file is best effort: if Redis is not able to create it
# nothing bad happens, the server will start and run normally.
#
# Note that on modern Linux systems "/run/redis.pid" is more conforming
# and should be used instead.
#
# 如果使用后台进程运行，那么我们需要指定一个pid文件
pidfile /var/run/redis_6379.pid
# Specify the server verbosity level.
# This can be one of:
# debug (a lot of information, useful for development/testing)
# verbose (many rarely useful info, but not a mess like the debug level)
# notice (moderately verbose, what you want in production probably)
# warning (only very important / critical messages are logged)
# 设置日志级别
loglevel notice
# Specify the log file name. Also the empty string can be used to force
# Redis to log on the standard output. Note that if you use standard
# output for logging but daemonize, logs will be sent to /dev/null
# 设置日志保存的文件名
logfile ""
# To enable logging to the system logger, just set 'syslog-enabled' to yes,
# and optionally update the other syslog parameters to suit your needs.
# syslog-enabled no
# Specify the syslog identity.
# syslog-ident redis
# Specify the syslog facility. Must be USER or between LOCAL0-LOCAL7.
# syslog-facility local0
# To disable the built in crash log, which will possibly produce cleaner core
# dumps when they are needed, uncomment the following:
#
# crash-log-enabled no
# To disable the fast memory check that's run as part of the crash log, which
# will possibly let redis terminate sooner, uncomment the following:
#
# crash-memcheck-enabled no
# Set the number of databases. The default database is DB 0, you can select
# a different one on a per-connection basis using SELECT <dbid> where
# dbid is a number between 0 and 'databases'-1
# 设置默认的数据库个数
databases 16
# By default Redis shows an ASCII art logo only when started to log to the
# standard output and if the standard output is a TTY and syslog logging is
# disabled. Basically this means that normally a logo is displayed only in
# interactive sessions.
#
# However it is possible to force the pre-4.0 behavior and always show a
# ASCII art logo in startup logs by setting the following option to yes.
# 启动log显示
always-show-logo no
# By default, Redis modifies the process title (as seen in 'top' and 'ps') to
# provide some runtime information. It is possible to disable this and leave
# the process name as executed by setting the following to no.
set-proc-title yes
# When changing the process title, Redis uses the following template to construct
# the modified title.
#
# Template variables are specified in curly brackets. The following variables are
# supported:
#
# {title} Name of process as executed if parent, or type of child process.
# {listen-addr} Bind address or '*' followed by TCP or TLS port listening on, or
# Unix socket if only that's available.
# {server-mode} Special mode, i.e. "[sentinel]" or "[cluster]".
# {port} TCP port listening on, or 0.
# {tls-port} TLS port listening on, or 0.
# {unixsocket} Unix domain socket listening on, or "".
# {config-file} Name of configuration file used.
#
proc-title-template "{title} {listen-addr} {server-mode}"
################################ SNAPSHOTTING ################################
# Save the DB to disk.
#
# save <seconds> <changes>
#
# Redis will save the DB if both the given number of seconds and the given
# number of write operations against the DB occurred.
#
# Snapshotting can be completely disabled with a single empty string argument
# as in following example:
#
# save ""
#
# Unless specified otherwise, by default Redis will save the DB:
# * After 3600 seconds (an hour) if at least 1 key changed
# * After 300 seconds (5 minutes) if at least 100 keys changed
# * After 60 seconds if at least 10000 keys changed
#
# You can set these explicitly by uncommenting the three following lines.
# rdb的保存配置 在3600秒内，如果有一个值修改，则保存一次，我们可以自己配置
# save 3600 1
# save 300 100
# save 60 10000
# By default Redis will stop accepting writes if RDB snapshots are enabled
# (at least one save point) and the latest background save failed.
# This will make the user aware (in a hard way) that data is not persisting
# on disk properly, otherwise chances are that no one will notice and some
# disaster will happen.
#
# If the background saving process will start working again Redis will
# automatically allow writes again.
#
# However if you have setup your proper monitoring of the Redis server
# and persistence, you may want to disable this feature so that Redis will
# continue to work as usual even if there are problems with disk,
# permissions, and so forth.
# 持久化失败后是否继续工作
stop-writes-on-bgsave-error yes
# Compress string objects using LZF when dump .rdb databases?
# By default compression is enabled as it's almost always a win.
# If you want to save some CPU in the saving child set it to 'no' but
# the dataset will likely be bigger if you have compressible values or keys.
# 是否压缩rdb 文件
rdbcompression yes
# Since version 5 of RDB a CRC64 checksum is placed at the end of the file.
# This makes the format more resistant to corruption but there is a performance
# hit to pay (around 10%) when saving and loading RDB files, so you can disable it
# for maximum performances.
#
# RDB files created with checksum disabled have a checksum of zero that will
# tell the loading code to skip the check.
# 保存rdb是进行错误校验
rdbchecksum yes
# Enables or disables full sanitation checks for ziplist and listpack etc when
# loading an RDB or RESTORE payload. This reduces the chances of a assertion or
# crash later on while processing commands.
# Options:
# no - Never perform full sanitation
# yes - Always perform full sanitation
# clients - Perform full sanitation only for user connections.
# Excludes: RDB files, RESTORE commands received from the master
# connection, and client connections which have the
# skip-sanitize-payload ACL flag.
# The default should be 'clients' but since it currently affects cluster
# resharding via MIGRATE, it is temporarily set to 'no' by default.
#
# sanitize-dump-payload no
# The filename where to dump the DB
# rdb保存的文件名
dbfilename dump.rdb
# Remove RDB files used by replication in instances without persistence
# enabled. By default this option is disabled, however there are environments
# where for regulations or other security concerns, RDB files persisted on
# disk by masters in order to feed replicas, or stored on disk by replicas
# in order to load them for the initial synchronization, should be deleted
# ASAP. Note that this option ONLY WORKS in instances that have both AOF
# and RDB persistence disabled, otherwise is completely ignored.
#
# An alternative (and sometimes better) way to obtain the same effect is
# to use diskless replication on both master and replicas instances. However
# in the case of replicas, diskless is not always an option.
# 保存时是否删除同步文件
rdb-del-sync-files no
# The working directory.
#
# The DB will be written inside this directory, with the filename specified
# above using the 'dbfilename' configuration directive.
#
# The Append Only File will also be created inside this directory.
#
# Note that you must specify a directory here, not a file name.
# rdb 保存的目录默认是当前文件，也就是启动目录
dir ./
################################# REPLICATION #################################
#
# 主从配置，集群配置
# Master-Replica replication. Use replicaof to make a Redis instance a copy of
# another Redis server. A few things to understand ASAP about Redis replication.
#
# +------------------+ +---------------+
# | Master | ---> | Replica |
# | (receive writes) | | (exact copy) |
# +------------------+ +---------------+
#
# 1) Redis replication is asynchronous, but you can configure a master to
# stop accepting writes if it appears to be not connected with at least
# a given number of replicas.
# 2) Redis replicas are able to perform a partial resynchronization with the
# master if the replication link is lost for a relatively small amount of
# time. You may want to configure the replication backlog size (see the next
# sections of this file) with a sensible value depending on your needs.
# 3) Replication is automatic and does not need user intervention. After a
# network partition replicas automatically try to reconnect to masters
# and resynchronize with them.
#
# replicaof <masterip> <masterport>
# If the master is password protected (using the "requirepass" configuration
# directive below) it is possible to tell the replica to authenticate before
# starting the replication synchronization process, otherwise the master will
# refuse the replica request.
#
# masterauth <master-password>
#
# However this is not enough if you are using Redis ACLs (for Redis version
# 6 or greater), and the default user is not capable of running the PSYNC
# command and/or other commands needed for replication. In this case it's
# better to configure a special user to use with replication, and specify the
# masteruser configuration as such:
#
# masteruser <username>
#
# When masteruser is specified, the replica will authenticate against its
# master using the new AUTH form: AUTH <username> <password>.
# When a replica loses its connection with the master, or when the replication
# is still in progress, the replica can act in two different ways:
#
# 1) if replica-serve-stale-data is set to 'yes' (the default) the replica will
# still reply to client requests, possibly with out of date data, or the
# data set may just be empty if this is the first synchronization.
#
# 2) If replica-serve-stale-data is set to 'no' the replica will reply with
# an error "SYNC with master in progress" to all commands except:
# INFO, REPLICAOF, AUTH, PING, SHUTDOWN, REPLCONF, ROLE, CONFIG, SUBSCRIBE,
# UNSUBSCRIBE, PSUBSCRIBE, PUNSUBSCRIBE, PUBLISH, PUBSUB, COMMAND, POST,
# HOST and LATENCY.
#
replica-serve-stale-data yes
# You can configure a replica instance to accept writes or not. Writing against
# a replica instance may be useful to store some ephemeral data (because data
# written on a replica will be easily deleted after resync with the master) but
# may also cause problems if clients are writing to it because of a
# misconfiguration.
#
# Since Redis 2.6 by default replicas are read-only.
#
# Note: read only replicas are not designed to be exposed to untrusted clients
# on the internet. It's just a protection layer against misuse of the instance.
# Still a read only replica exports by default all the administrative commands
# such as CONFIG, DEBUG, and so forth. To a limited extent you can improve
# security of read only replicas using 'rename-command' to shadow all the
# administrative / dangerous commands.
replica-read-only yes
# Replication SYNC strategy: disk or socket.
#
# New replicas and reconnecting replicas that are not able to continue the
# replication process just receiving differences, need to do what is called a
# "full synchronization". An RDB file is transmitted from the master to the
# replicas.
#
# The transmission can happen in two different ways:
#
# 1) Disk-backed: The Redis master creates a new process that writes the RDB
# file on disk. Later the file is transferred by the parent
# process to the replicas incrementally.
# 2) Diskless: The Redis master creates a new process that directly writes the
# RDB file to replica sockets, without touching the disk at all.
#
# With disk-backed replication, while the RDB file is generated, more replicas
# can be queued and served with the RDB file as soon as the current child
# producing the RDB file finishes its work. With diskless replication instead
# once the transfer starts, new replicas arriving will be queued and a new
# transfer will start when the current one terminates.
#
# When diskless replication is used, the master waits a configurable amount of
# time (in seconds) before starting the transfer in the hope that multiple
# replicas will arrive and the transfer can be parallelized.
#
# With slow disks and fast (large bandwidth) networks, diskless replication
# works better.
repl-diskless-sync no
# When diskless replication is enabled, it is possible to configure the delay
# the server waits in order to spawn the child that transfers the RDB via socket
# to the replicas.
#
# This is important since once the transfer starts, it is not possible to serve
# new replicas arriving, that will be queued for the next RDB transfer, so the
# server waits a delay in order to let more replicas arrive.
#
# The delay is specified in seconds, and by default is 5 seconds. To disable
# it entirely just set it to 0 seconds and the transfer will start ASAP.
repl-diskless-sync-delay 5
# -----------------------------------------------------------------------------
# WARNING: RDB diskless load is experimental. Since in this setup the replica
# does not immediately store an RDB on disk, it may cause data loss during
# failovers. RDB diskless load + Redis modules not handling I/O reads may also
# cause Redis to abort in case of I/O errors during the initial synchronization
# stage with the master. Use only if you know what you are doing.
# -----------------------------------------------------------------------------
#
# Replica can load the RDB it reads from the replication link directly from the
# socket, or store the RDB to a file and read that file after it was completely
# received from the master.
#
# In many cases the disk is slower than the network, and storing and loading
# the RDB file may increase replication time (and even increase the master's
# Copy on Write memory and salve buffers).
# However, parsing the RDB file directly from the socket may mean that we have
# to flush the contents of the current database before the full rdb was
# received. For this reason we have the following options:
#
# "disabled" - Don't use diskless load (store the rdb file to the disk first)
# "on-empty-db" - Use diskless load only when it is completely safe.
# "swapdb" - Keep a copy of the current db contents in RAM while parsing
# the data directly from the socket. note that this requires
# sufficient memory, if you don't have it, you risk an OOM kill.
repl-diskless-load disabled
# Replicas send PINGs to server in a predefined interval. It's possible to
# change this interval with the repl_ping_replica_period option. The default
# value is 10 seconds.
#
# repl-ping-replica-period 10
# The following option sets the replication timeout for:
#
# 1) Bulk transfer I/O during SYNC, from the point of view of replica.
# 2) Master timeout from the point of view of replicas (data, pings).
# 3) Replica timeout from the point of view of masters (REPLCONF ACK pings).
#
# It is important to make sure that this value is greater than the value
# specified for repl-ping-replica-period otherwise a timeout will be detected
# every time there is low traffic between the master and the replica. The default
# value is 60 seconds.
#
# repl-timeout 60
# Disable TCP_NODELAY on the replica socket after SYNC?
#
# If you select "yes" Redis will use a smaller number of TCP packets and
# less bandwidth to send data to replicas. But this can add a delay for
# the data to appear on the replica side, up to 40 milliseconds with
# Linux kernels using a default configuration.
#
# If you select "no" the delay for data to appear on the replica side will
# be reduced but more bandwidth will be used for replication.
#
# By default we optimize for low latency, but in very high traffic conditions
# or when the master and replicas are many hops away, turning this to "yes" may
# be a good idea.
repl-disable-tcp-nodelay no
# Set the replication backlog size. The backlog is a buffer that accumulates
# replica data when replicas are disconnected for some time, so that when a
# replica wants to reconnect again, often a full resync is not needed, but a
# partial resync is enough, just passing the portion of data the replica
# missed while disconnected.
#
# The bigger the replication backlog, the longer the replica can endure the
# disconnect and later be able to perform a partial resynchronization.
#
# The backlog is only allocated if there is at least one replica connected.
#
# repl-backlog-size 1mb
# After a master has no connected replicas for some time, the backlog will be
# freed. The following option configures the amount of seconds that need to
# elapse, starting from the time the last replica disconnected, for the backlog
# buffer to be freed.
#
# Note that replicas never free the backlog for timeout, since they may be
# promoted to masters later, and should be able to correctly "partially
# resynchronize" with other replicas: hence they should always accumulate backlog.
#
# A value of 0 means to never release the backlog.
#
# repl-backlog-ttl 3600
# The replica priority is an integer number published by Redis in the INFO
# output. It is used by Redis Sentinel in order to select a replica to promote
# into a master if the master is no longer working correctly.
#
# A replica with a low priority number is considered better for promotion, so
# for instance if there are three replicas with priority 10, 100, 25 Sentinel
# will pick the one with priority 10, that is the lowest.
#
# However a special priority of 0 marks the replica as not able to perform the
# role of master, so a replica with priority of 0 will never be selected by
# Redis Sentinel for promotion.
#
# By default the priority is 100.
replica-priority 100
# -----------------------------------------------------------------------------
# By default, Redis Sentinel includes all replicas in its reports. A replica
# can be excluded from Redis Sentinel's announcements. An unannounced replica
# will be ignored by the 'sentinel replicas <master>' command and won't be
# exposed to Redis Sentinel's clients.
#
# This option does not change the behavior of replica-priority. Even with
# replica-announced set to 'no', the replica can be promoted to master. To
# prevent this behavior, set replica-priority to 0.
#
# replica-announced yes
# It is possible for a master to stop accepting writes if there are less than
# N replicas connected, having a lag less or equal than M seconds.
#
# The N replicas need to be in "online" state.
#
# The lag in seconds, that must be <= the specified value, is calculated from
# the last ping received from the replica, that is usually sent every second.
#
# This option does not GUARANTEE that N replicas will accept the write, but
# will limit the window of exposure for lost writes in case not enough replicas
# are available, to the specified number of seconds.
#
# For example to require at least 3 replicas with a lag <= 10 seconds use:
#
# min-replicas-to-write 3
# min-replicas-max-lag 10
#
# Setting one or the other to 0 disables the feature.
#
# By default min-replicas-to-write is set to 0 (feature disabled) and
# min-replicas-max-lag is set to 10.
# A Redis master is able to list the address and port of the attached
# replicas in different ways. For example the "INFO replication" section
# offers this information, which is used, among other tools, by
# Redis Sentinel in order to discover replica instances.
# Another place where this info is available is in the output of the
# "ROLE" command of a master.
#
# The listed IP address and port normally reported by a replica is
# obtained in the following way:
#
# IP: The address is auto detected by checking the peer address
# of the socket used by the replica to connect with the master.
#
# Port: The port is communicated by the replica during the replication
# handshake, and is normally the port that the replica is using to
# listen for connections.
#
# However when port forwarding or Network Address Translation (NAT) is
# used, the replica may actually be reachable via different IP and port
# pairs. The following two options can be used by a replica in order to
# report to its master a specific set of IP and port, so that both INFO
# and ROLE will report those values.
#
# There is no need to use both the options if you need to override just
# the port or the IP address.
#
# replica-announce-ip 5.5.5.5
# replica-announce-port 1234
############################### KEYS TRACKING #################################
# Redis implements server assisted support for client side caching of values.
# This is implemented using an invalidation table that remembers, using
# a radix key indexed by key name, what clients have which keys. In turn
# this is used in order to send invalidation messages to clients. Please
# check this page to understand more about the feature:
#
# https://redis.io/topics/client-side-caching
#
# When tracking is enabled for a client, all the read only queries are assumed
# to be cached: this will force Redis to store information in the invalidation
# table. When keys are modified, such information is flushed away, and
# invalidation messages are sent to the clients. However if the workload is
# heavily dominated by reads, Redis could use more and more memory in order
# to track the keys fetched by many clients.
#
# For this reason it is possible to configure a maximum fill value for the
# invalidation table. By default it is set to 1M of keys, and once this limit
# is reached, Redis will start to evict keys in the invalidation table
# even if they were not modified, just to reclaim memory: this will in turn
# force the clients to invalidate the cached values. Basically the table
# maximum size is a trade off between the memory you want to spend server
# side to track information about who cached what, and the ability of clients
# to retain cached objects in memory.
#
# If you set the value to 0, it means there are no limits, and Redis will
# retain as many keys as needed in the invalidation table.
# In the "stats" INFO section, you can find information about the number of
# keys in the invalidation table at every given moment.
#
# Note: when key tracking is used in broadcasting mode, no memory is used
# in the server side so this setting is useless.
#
# tracking-table-max-keys 1000000
################################## SECURITY ###################################
# 安全校验相关配置
# Warning: since Redis is pretty fast, an outside user can try up to
# 1 million passwords per second against a modern box. This means that you
# should use very strong passwords, otherwise they will be very easy to break.
# Note that because the password is really a shared secret between the client
# and the server, and should not be memorized by any human, the password
# can be easily a long string from /dev/urandom or whatever, so by using a
# long and unguessable password no brute force attack will be possible.
# Redis ACL users are defined in the following format:
#
# user <username> ... acl rules ...
#
# For example:
#
# user worker +@list +@connection ~jobs:* on >ffa9203c493aa99
#
# The special username "default" is used for new connections. If this user
# has the "nopass" rule, then new connections will be immediately authenticated
# as the "default" user without the need of any password provided via the
# AUTH command. Otherwise if the "default" user is not flagged with "nopass"
# the connections will start in not authenticated state, and will require
# AUTH (or the HELLO command AUTH option) in order to be authenticated and
# start to work.
#
# The ACL rules that describe what a user can do are the following:
#
# on Enable the user: it is possible to authenticate as this user.
# off Disable the user: it's no longer possible to authenticate
# with this user, however the already authenticated connections
# will still work.
# skip-sanitize-payload RESTORE dump-payload sanitation is skipped.
# sanitize-payload RESTORE dump-payload is sanitized (default).
# +<command> Allow the execution of that command
# -<command> Disallow the execution of that command
# +@<category> Allow the execution of all the commands in such category
# with valid categories are like @admin, @set, @sortedset, ...
# and so forth, see the full list in the server.c file where
# the Redis command table is described and defined.
# The special category @all means all the commands, but currently
# present in the server, and that will be loaded in the future
# via modules.
# +<command>|subcommand Allow a specific subcommand of an otherwise
# disabled command. Note that this form is not
# allowed as negative like -DEBUG|SEGFAULT, but
# only additive starting with "+".
# allcommands Alias for +@all. Note that it implies the ability to execute
# all the future commands loaded via the modules system.
# nocommands Alias for -@all.
# ~<pattern> Add a pattern of keys that can be mentioned as part of
# commands. For instance ~* allows all the keys. The pattern
# is a glob-style pattern like the one of KEYS.
# It is possible to specify multiple patterns.
# allkeys Alias for ~*
# resetkeys Flush the list of allowed keys patterns.
# &<pattern> Add a glob-style pattern of Pub/Sub channels that can be
# accessed by the user. It is possible to specify multiple channel
# patterns.
# allchannels Alias for &*
# resetchannels Flush the list of allowed channel patterns.
# ><password> Add this password to the list of valid password for the user.
# For example >mypass will add "mypass" to the list.
# This directive clears the "nopass" flag (see later).
# <<password> Remove this password from the list of valid passwords.
# nopass All the set passwords of the user are removed, and the user
# is flagged as requiring no password: it means that every
# password will work against this user. If this directive is
# used for the default user, every new connection will be
# immediately authenticated with the default user without
# any explicit AUTH command required. Note that the "resetpass"
# directive will clear this condition.
# resetpass Flush the list of allowed passwords. Moreover removes the
# "nopass" status. After "resetpass" the user has no associated
# passwords and there is no way to authenticate without adding
# some password (or setting it as "nopass" later).
# reset Performs the following actions: resetpass, resetkeys, off,
# -@all. The user returns to the same state it has immediately
# after its creation.
#
# ACL rules can be specified in any order: for instance you can start with
# passwords, then flags, or key patterns. However note that the additive
# and subtractive rules will CHANGE MEANING depending on the ordering.
# For instance see the following example:
#
# user alice on +@all -DEBUG ~* >somepassword
#
# This will allow "alice" to use all the commands with the exception of the
# DEBUG command, since +@all added all the commands to the set of the commands
# alice can use, and later DEBUG was removed. However if we invert the order
# of two ACL rules the result will be different:
#
# user alice on -DEBUG +@all ~* >somepassword
#
# Now DEBUG was removed when alice had yet no commands in the set of allowed
# commands, later all the commands are added, so the user will be able to
# execute everything.
#
# Basically ACL rules are processed left-to-right.
#
# For more information about ACL configuration please refer to
# the Redis web site at https://redis.io/topics/acl
# ACL LOG
#
# The ACL Log tracks failed commands and authentication events associated
# with ACLs. The ACL Log is useful to troubleshoot failed commands blocked
# by ACLs. The ACL Log is stored in memory. You can reclaim memory with
# ACL LOG RESET. Define the maximum entry length of the ACL Log below.
acllog-max-len 128
# Using an external ACL file
#
# Instead of configuring users here in this file, it is possible to use
# a stand-alone file just listing users. The two methods cannot be mixed:
# if you configure users here and at the same time you activate the external
# ACL file, the server will refuse to start.
#
# The format of the external ACL user file is exactly the same as the
# format that is used inside redis.conf to describe users.
#
# aclfile /etc/redis/users.acl
# IMPORTANT NOTE: starting with Redis 6 "requirepass" is just a compatibility
# layer on top of the new ACL system. The option effect will be just setting
# the password for the default user. Clients will still authenticate using
# AUTH <password> as usually, or more explicitly with AUTH default <password>
# if they follow the new protocol: both will work.
#
# The requirepass is not compatable with aclfile option and the ACL LOAD
# command, these will cause requirepass to be ignored.
# 连接redis 配置的密码
# requirepass foobared
# requirepass 123456
# 也可以通过命令来设置 set requirepass "123456",
# 使用密码登录命令 auth 123456
# New users are initialized with restrictive permissions by default, via the
# equivalent of this ACL rule 'off resetkeys -@all'. Starting with Redis 6.2, it
# is possible to manage access to Pub/Sub channels with ACL rules as well. The
# default Pub/Sub channels permission if new users is controlled by the
# acl-pubsub-default configuration directive, which accepts one of these values:
#
# allchannels: grants access to all Pub/Sub channels
# resetchannels: revokes access to all Pub/Sub channels
#
# To ensure backward compatibility while upgrading Redis 6.0, acl-pubsub-default
# defaults to the 'allchannels' permission.
#
# Future compatibility note: it is very likely that in a future version of Redis
# the directive's default of 'allchannels' will be changed to 'resetchannels' in
# order to provide better out-of-the-box Pub/Sub security. Therefore, it is
# recommended that you explicitly define Pub/Sub permissions for all users
# rather then rely on implicit default values. Once you've set explicit
# Pub/Sub for all existing users, you should uncomment the following line.
#
# acl-pubsub-default resetchannels
# Command renaming (DEPRECATED).
#
# ------------------------------------------------------------------------
# WARNING: avoid using this option if possible. Instead use ACLs to remove
# commands from the default user, and put them only in some admin user you
# create for administrative purposes.
# ------------------------------------------------------------------------
#
# It is possible to change the name of dangerous commands in a shared
# environment. For instance the CONFIG command may be renamed into something
# hard to guess so that it will still be available for internal-use tools
# but not available for general clients.
#
# Example:
#
# rename-command CONFIG b840fc02d524045429941cc15f59e41cb7be6c52
#
# It is also possible to completely kill a command by renaming it into
# an empty string:
#
# rename-command CONFIG ""
#
# Please note that changing the name of commands that are logged into the
# AOF file or transmitted to replicas may cause problems.
################################### CLIENTS ####################################
# Set the max number of connected clients at the same time. By default
# this limit is set to 10000 clients, however if the Redis server is not
# able to configure the process file limit to allow for the specified limit
# the max number of allowed clients is set to the current file limit
# minus 32 (as Redis reserves a few file descriptors for internal uses).
#
# Once the limit is reached Redis will close all the new connections sending
# an error 'max number of clients reached'.
#
# IMPORTANT: When Redis Cluster is used, the max number of connections is also
# shared with the cluster bus: every node in the cluster will use two
# connections, one incoming and another outgoing. It is important to size the
# limit accordingly in case of very large clusters.
# 设置连接redis 最大客户端数量
# maxclients 10000
############################## MEMORY MANAGEMENT ################################
# Set a memory usage limit to the specified amount of bytes.
# When the memory limit is reached Redis will try to remove keys
# according to the eviction policy selected (see maxmemory-policy).
#
# If Redis can't remove keys according to the policy, or if the policy is
# set to 'noeviction', Redis will start to reply with errors to commands
# that would use more memory, like SET, LPUSH, and so on, and will continue
# to reply to read-only commands like GET.
#
# This option is usually useful when using Redis as an LRU or LFU cache, or to
# set a hard memory limit for an instance (using the 'noeviction' policy).
#
# WARNING: If you have replicas attached to an instance with maxmemory on,
# the size of the output buffers needed to feed the replicas are subtracted
# from the used memory count, so that network problems / resyncs will
# not trigger a loop where keys are evicted, and in turn the output
# buffer of replicas is full with DELs of keys evicted triggering the deletion
# of more keys, and so forth until the database is completely emptied.
#
# In short... if you have replicas attached it is suggested that you set a lower
# limit for maxmemory so that there is some free RAM on the system for replica
# output buffers (but this is not needed if the policy is 'noeviction').
#
# 最大的内存设置
# maxmemory <bytes>
# MAXMEMORY POLICY: how Redis will select what to remove when maxmemory
# is reached. You can select one from the following behaviors:
#
# volatile-lru -> Evict using approximated LRU, only keys with an expire set.
# allkeys-lru -> Evict any key using approximated LRU.
# volatile-lfu -> Evict using approximated LFU, only keys with an expire set.
# allkeys-lfu -> Evict any key using approximated LFU.
# volatile-random -> Remove a random key having an expire set.
# allkeys-random -> Remove a random key, any key.
# volatile-ttl -> Remove the key with the nearest expire time (minor TTL)
# noeviction -> Don't evict anything, just return an error on write operations.
#
# LRU means Least Recently Used
# LFU means Least Frequently Used
#
# Both LRU, LFU and volatile-ttl are implemented using approximated
# randomized algorithms.
#
# Note: with any of the above policies, when there are no suitable keys for
# eviction, Redis will return an error on write operations that require
# more memory. These are usually commands that create new keys, add data or
# modify existing keys. A few examples are: SET, INCR, HSET, LPUSH, SUNIONSTORE,
# SORT (due to the STORE argument), and EXEC (if the transaction includes any
# command that requires memory).
#
# The default is:
# 内存上限的处理策略
# maxmemory-policy noeviction
# 1、volatile-lru：只对设置了过期时间的key进行LRU（默认值）
# 2、allkeys-lru ： 删除lru算法的key
# 3、volatile-random：随机删除即将过期key
# 4、allkeys-random：随机删除
# 5、volatile-ttl ： 删除即将过期的
# 6、noeviction ： 永不过期，返回错误
# LRU, LFU and minimal TTL algorithms are not precise algorithms but approximated
# algorithms (in order to save memory), so you can tune it for speed or
# accuracy. By default Redis will check five keys and pick the one that was
# used least recently, you can change the sample size using the following
# configuration directive.
#
# The default of 5 produces good enough results. 10 Approximates very closely
# true LRU but costs more CPU. 3 is faster but not very accurate.
# 最大内存配置 5G
# maxmemory-samples 5
# Eviction processing is designed to function well with the default setting.
# If there is an unusually large amount of write traffic, this value may need to
# be increased. Decreasing this value may reduce latency at the risk of
# eviction processing effectiveness
# 0 = minimum latency, 10 = default, 100 = process without regard to latency
# 写入流最大配置
# maxmemory-eviction-tenacity 10
# Starting from Redis 5, by default a replica will ignore its maxmemory setting
# (unless it is promoted to master after a failover or manually). It means
# that the eviction of keys will be just handled by the master, sending the
# DEL commands to the replica as keys evict in the master side.
#
# This behavior ensures that masters and replicas stay consistent, and is usually
# what you want, however if your replica is writable, or you want the replica
# to have a different memory setting, and you are sure all the writes performed
# to the replica are idempotent, then you may change this default (but be sure
# to understand what you are doing).
#
# Note that since the replica by default does not evict, it may end using more
# memory than the one set via maxmemory (there are certain buffers that may
# be larger on the replica, or data structures may sometimes take more memory
# and so forth). So make sure you monitor your replicas and make sure they
# have enough memory to never hit a real out-of-memory condition before the
# master hits the configured maxmemory setting.
#
# replica-ignore-maxmemory yes
# Redis reclaims expired keys in two ways: upon access when those keys are
# found to be expired, and also in background, in what is called the
# "active expire key". The key space is slowly and interactively scanned
# looking for expired keys to reclaim, so that it is possible to free memory
# of keys that are expired and will never be accessed again in a short time.
#
# The default effort of the expire cycle will try to avoid having more than
# ten percent of expired keys still in memory, and will try to avoid consuming
# more than 25% of total memory and to add latency to the system. However
# it is possible to increase the expire "effort" that is normally set to
# "1", to a greater value, up to the value "10". At its maximum value the
# system will use more CPU, longer cycles (and technically may introduce
# more latency), and will tolerate less already expired keys still present
# in the system. It's a tradeoff between memory, CPU and latency.
#
# active-expire-effort 1
############################# LAZY FREEING ####################################
# Redis has two primitives to delete keys. One is called DEL and is a blocking
# deletion of the object. It means that the server stops processing new commands
# in order to reclaim all the memory associated with an object in a synchronous
# way. If the key deleted is associated with a small object, the time needed
# in order to execute the DEL command is very small and comparable to most other
# O(1) or O(log_N) commands in Redis. However if the key is associated with an
# aggregated value containing millions of elements, the server can block for
# a long time (even seconds) in order to complete the operation.
#
# For the above reasons Redis also offers non blocking deletion primitives
# such as UNLINK (non blocking DEL) and the ASYNC option of FLUSHALL and
# FLUSHDB commands, in order to reclaim memory in background. Those commands
# are executed in constant time. Another thread will incrementally free the
# object in the background as fast as possible.
#
# DEL, UNLINK and ASYNC option of FLUSHALL and FLUSHDB are user-controlled.
# It's up to the design of the application to understand when it is a good
# idea to use one or the other. However the Redis server sometimes has to
# delete keys or flush the whole database as a side effect of other operations.
# Specifically Redis deletes objects independently of a user call in the
# following scenarios:
#
# 1) On eviction, because of the maxmemory and maxmemory policy configurations,
# in order to make room for new data, without going over the specified
# memory limit.
# 2) Because of expire: when a key with an associated time to live (see the
# EXPIRE command) must be deleted from memory.
# 3) Because of a side effect of a command that stores data on a key that may
# already exist. For example the RENAME command may delete the old key
# content when it is replaced with another one. Similarly SUNIONSTORE
# or SORT with STORE option may delete existing keys. The SET command
# itself removes any old content of the specified key in order to replace
# it with the specified string.
# 4) During replication, when a replica performs a full resynchronization with
# its master, the content of the whole database is removed in order to
# load the RDB file just transferred.
#
# In all the above cases the default is to delete objects in a blocking way,
# like if DEL was called. However you can configure each case specifically
# in order to instead release memory in a non-blocking way like if UNLINK
# was called, using the following configuration directives.
lazyfree-lazy-eviction no
lazyfree-lazy-expire no
lazyfree-lazy-server-del no
replica-lazy-flush no
# It is also possible, for the case when to replace the user code DEL calls
# with UNLINK calls is not easy, to modify the default behavior of the DEL
# command to act exactly like UNLINK, using the following configuration
# directive:
lazyfree-lazy-user-del no
# FLUSHDB, FLUSHALL, and SCRIPT FLUSH support both asynchronous and synchronous
# deletion, which can be controlled by passing the [SYNC|ASYNC] flags into the
# commands. When neither flag is passed, this directive will be used to determine
# if the data should be deleted asynchronously.
lazyfree-lazy-user-flush no
################################ THREADED I/O #################################
# Redis is mostly single threaded, however there are certain threaded
# operations such as UNLINK, slow I/O accesses and other things that are
# performed on side threads.
#
# Now it is also possible to handle Redis clients socket reads and writes
# in different I/O threads. Since especially writing is so slow, normally
# Redis users use pipelining in order to speed up the Redis performances per
# core, and spawn multiple instances in order to scale more. Using I/O
# threads it is possible to easily speedup two times Redis without resorting
# to pipelining nor sharding of the instance.
#
# By default threading is disabled, we suggest enabling it only in machines
# that have at least 4 or more cores, leaving at least one spare core.
# Using more than 8 threads is unlikely to help much. We also recommend using
# threaded I/O only if you actually have performance problems, with Redis
# instances being able to use a quite big percentage of CPU time, otherwise
# there is no point in using this feature.
#
# So for instance if you have a four cores boxes, try to use 2 or 3 I/O
# threads, if you have a 8 cores, try to use 6 threads. In order to
# enable I/O threads use the following configuration directive:
#
# io-threads 4
#
# Setting io-threads to 1 will just use the main thread as usual.
# When I/O threads are enabled, we only use threads for writes, that is
# to thread the write(2) syscall and transfer the client buffers to the
# socket. However it is also possible to enable threading of reads and
# protocol parsing using the following configuration directive, by setting
# it to yes:
#
# io-threads-do-reads no
#
# Usually threading reads doesn't help much.
#
# NOTE 1: This configuration directive cannot be changed at runtime via
# CONFIG SET. Aso this feature currently does not work when SSL is
# enabled.
#
# NOTE 2: If you want to test the Redis speedup using redis-benchmark, make
# sure you also run the benchmark itself in threaded mode, using the
# --threads option to match the number of Redis threads, otherwise you'll not
# be able to notice the improvements.
############################ KERNEL OOM CONTROL ##############################
# On Linux, it is possible to hint the kernel OOM killer on what processes
# should be killed first when out of memory.
#
# Enabling this feature makes Redis actively control the oom_score_adj value
# for all its processes, depending on their role. The default scores will
# attempt to have background child processes killed before all others, and
# replicas killed before masters.
#
# Redis supports three options:
#
# no: Don't make changes to oom-score-adj (default).
# yes: Alias to "relative" see below.
# absolute: Values in oom-score-adj-values are written as is to the kernel.
# relative: Values are used relative to the initial value of oom_score_adj when
# the server starts and are then clamped to a range of -1000 to 1000.
# Because typically the initial value is 0, they will often match the
# absolute values.
oom-score-adj no
# When oom-score-adj is used, this directive controls the specific values used
# for master, replica and background child processes. Values range -2000 to
# 2000 (higher means more likely to be killed).
#
# Unprivileged processes (not root, and without CAP_SYS_RESOURCE capabilities)
# can freely increase their value, but not decrease it below its initial
# settings. This means that setting oom-score-adj to "relative" and setting the
# oom-score-adj-values to positive values will always succeed.
oom-score-adj-values 0 200 800
#################### KERNEL transparent hugepage CONTROL ######################
# Usually the kernel Transparent Huge Pages control is set to "madvise" or
# or "never" by default (/sys/kernel/mm/transparent_hugepage/enabled), in which
# case this config has no effect. On systems in which it is set to "always",
# redis will attempt to disable it specifically for the redis process in order
# to avoid latency problems specifically with fork(2) and CoW.
# If for some reason you prefer to keep it enabled, you can set this config to
# "no" and the kernel global to "always".
disable-thp yes
############################## APPEND ONLY MODE ###############################
# aof 持久化配置
# By default Redis asynchronously dumps the dataset on disk. This mode is
# good enough in many applications, but an issue with the Redis process or
# a power outage may result into a few minutes of writes lost (depending on
# the configured save points).
#
# The Append Only File is an alternative persistence mode that provides
# much better durability. For instance using the default data fsync policy
# (see later in the config file) Redis can lose just one second of writes in a
# dramatic event like a server power outage, or a single write if something
# wrong with the Redis process itself happens, but the operating system is
# still running correctly.
#
# AOF and RDB persistence can be enabled at the same time without problems.
# If the AOF is enabled on startup Redis will load the AOF, that is the file
# with the better durability guarantees.
#
# Please check https://redis.io/topics/persistence for more information.
# aof 持久化是否开启
appendonly no
# The name of the append only file (default: "appendonly.aof")
# 持久化的文件名
appendfilename "appendonly.aof"
# The fsync() call tells the Operating System to actually write data on disk
# instead of waiting for more data in the output buffer. Some OS will really flush
# data on disk, some other OS will just try to do it ASAP.
#
# Redis supports three different modes:
#
# no: don't fsync, just let the OS flush the data when it wants. Faster.
# always: fsync after every write to the append only log. Slow, Safest.
# everysec: fsync only one time every second. Compromise.
#
# The default is "everysec", as that's usually the right compromise between
# speed and data safety. It's up to you to understand if you can relax this to
# "no" that will let the operating system flush the output buffer when
# it wants, for better performances (but if you can live with the idea of
# some data loss consider the default persistence mode that's snapshotting),
# or on the contrary, use "always" that's very slow but a bit safer than
# everysec.
#
# More details please check the following article:
# http://antirez.com/post/redis-persistence-demystified.html
#
# If unsure, use "everysec".
# aof的同步方式
# appendfsync always #总是
appendfsync everysec #每秒
# appendfsync no # 不同步
# When the AOF fsync policy is set to always or everysec, and a background
# saving process (a background save or AOF log background rewriting) is
# performing a lot of I/O against the disk, in some Linux configurations
# Redis may block too long on the fsync() call. Note that there is no fix for
# this currently, as even performing fsync in a different thread will block
# our synchronous write(2) call.
#
# In order to mitigate this problem it's possible to use the following option
# that will prevent fsync() from being called in the main process while a
# BGSAVE or BGREWRITEAOF is in progress.
#
# This means that while another child is saving, the durability of Redis is
# the same as "appendfsync none". In practical terms, this means that it is
# possible to lose up to 30 seconds of log in the worst scenario (with the
# default Linux settings).
#
# If you have latency problems turn this to "yes". Otherwise leave it as
# "no" that is the safest pick from the point of view of durability.
no-appendfsync-on-rewrite no
# Automatic rewrite of the append only file.
# Redis is able to automatically rewrite the log file implicitly calling
# BGREWRITEAOF when the AOF log size grows by the specified percentage.
#
# This is how it works: Redis remembers the size of the AOF file after the
# latest rewrite (if no rewrite has happened since the restart, the size of
# the AOF at startup is used).
#
# This base size is compared to the current size. If the current size is
# bigger than the specified percentage, the rewrite is triggered. Also
# you need to specify a minimal size for the AOF file to be rewritten, this
# is useful to avoid rewriting the AOF file even if the percentage increase
# is reached but it is still pretty small.
#
# Specify a percentage of zero in order to disable the automatic AOF
# rewrite feature.
auto-aof-rewrite-percentage 100
auto-aof-rewrite-min-size 64mb
# An AOF file may be found to be truncated at the end during the Redis
# startup process, when the AOF data gets loaded back into memory.
# This may happen when the system where Redis is running
# crashes, especially when an ext4 filesystem is mounted without the
# data=ordered option (however this can't happen when Redis itself
# crashes or aborts but the operating system still works correctly).
#
# Redis can either exit with an error when this happens, or load as much
# data as possible (the default now) and start if the AOF file is found
# to be truncated at the end. The following option controls this behavior.
#
# If aof-load-truncated is set to yes, a truncated AOF file is loaded and
# the Redis server starts emitting a log to inform the user of the event.
# Otherwise if the option is set to no, the server aborts with an error
# and refuses to start. When the option is set to no, the user requires
# to fix the AOF file using the "redis-check-aof" utility before to restart
# the server.
#
# Note that if the AOF file will be found to be corrupted in the middle
# the server will still exit with an error. This option only applies when
# Redis will try to read more data from the AOF file but not enough bytes
# will be found.
aof-load-truncated yes
# When rewriting the AOF file, Redis is able to use an RDB preamble in the
# AOF file for faster rewrites and recoveries. When this option is turned
# on the rewritten AOF file is composed of two different stanzas:
#
# [RDB file][AOF tail]
#
# When loading, Redis recognizes that the AOF file starts with the "REDIS"
# string and loads the prefixed RDB file, then continues loading the AOF
# tail.
aof-use-rdb-preamble yes
################################ LUA SCRIPTING ###############################
# Max execution time of a Lua script in milliseconds.
#
# If the maximum execution time is reached Redis will log that a script is
# still in execution after the maximum allowed time and will start to
# reply to queries with an error.
#
# When a long running script exceeds the maximum execution time only the
# SCRIPT KILL and SHUTDOWN NOSAVE commands are available. The first can be
# used to stop a script that did not yet call any write commands. The second
# is the only way to shut down the server in the case a write command was
# already issued by the script but the user doesn't want to wait for the natural
# termination of the script.
#
# Set it to 0 or a negative value for unlimited execution without warnings.
lua-time-limit 5000
################################ REDIS CLUSTER ###############################
# Normal Redis instances can't be part of a Redis Cluster; only nodes that are
# started as cluster nodes can. In order to start a Redis instance as a
# cluster node enable the cluster support uncommenting the following:
#
# cluster-enabled yes
# Every cluster node has a cluster configuration file. This file is not
# intended to be edited by hand. It is created and updated by Redis nodes.
# Every Redis Cluster node requires a different cluster configuration file.
# Make sure that instances running in the same system do not have
# overlapping cluster configuration file names.
#
# cluster-config-file nodes-6379.conf
# Cluster node timeout is the amount of milliseconds a node must be unreachable
# for it to be considered in failure state.
# Most other internal time limits are a multiple of the node timeout.
#
# cluster-node-timeout 15000
# A replica of a failing master will avoid to start a failover if its data
# looks too old.
#
# There is no simple way for a replica to actually have an exact measure of
# its "data age", so the following two checks are performed:
#
# 1) If there are multiple replicas able to failover, they exchange messages
# in order to try to give an advantage to the replica with the best
# replication offset (more data from the master processed).
# Replicas will try to get their rank by offset, and apply to the start
# of the failover a delay proportional to their rank.
#
# 2) Every single replica computes the time of the last interaction with
# its master. This can be the last ping or command received (if the master
# is still in the "connected" state), or the time that elapsed since the
# disconnection with the master (if the replication link is currently down).
# If the last interaction is too old, the replica will not try to failover
# at all.
#
# The point "2" can be tuned by user. Specifically a replica will not perform
# the failover if, since the last interaction with the master, the time
# elapsed is greater than:
#
# (node-timeout * cluster-replica-validity-factor) + repl-ping-replica-period
#
# So for example if node-timeout is 30 seconds, and the cluster-replica-validity-factor
# is 10, and assuming a default repl-ping-replica-period of 10 seconds, the
# replica will not try to failover if it was not able to talk with the master
# for longer than 310 seconds.
#
# A large cluster-replica-validity-factor may allow replicas with too old data to failover
# a master, while a too small value may prevent the cluster from being able to
# elect a replica at all.
#
# For maximum availability, it is possible to set the cluster-replica-validity-factor
# to a value of 0, which means, that replicas will always try to failover the
# master regardless of the last time they interacted with the master.
# (However they'll always try to apply a delay proportional to their
# offset rank).
#
# Zero is the only value able to guarantee that when all the partitions heal
# the cluster will always be able to continue.
#
# cluster-replica-validity-factor 10
# Cluster replicas are able to migrate to orphaned masters, that are masters
# that are left without working replicas. This improves the cluster ability
# to resist to failures as otherwise an orphaned master can't be failed over
# in case of failure if it has no working replicas.
#
# Replicas migrate to orphaned masters only if there are still at least a
# given number of other working replicas for their old master. This number
# is the "migration barrier". A migration barrier of 1 means that a replica
# will migrate only if there is at least 1 other working replica for its master
# and so forth. It usually reflects the number of replicas you want for every
# master in your cluster.
#
# Default is 1 (replicas migrate only if their masters remain with at least
# one replica). To disable migration just set it to a very large value or
# set cluster-allow-replica-migration to 'no'.
# A value of 0 can be set but is useful only for debugging and dangerous
# in production.
#
# cluster-migration-barrier 1
# Turning off this option allows to use less automatic cluster configuration.
# It both disables migration to orphaned masters and migration from masters
# that became empty.
#
# Default is 'yes' (allow automatic migrations).
#
# cluster-allow-replica-migration yes
# By default Redis Cluster nodes stop accepting queries if they detect there
# is at least a hash slot uncovered (no available node is serving it).
# This way if the cluster is partially down (for example a range of hash slots
# are no longer covered) all the cluster becomes, eventually, unavailable.
# It automatically returns available as soon as all the slots are covered again.
#
# However sometimes you want the subset of the cluster which is working,
# to continue to accept queries for the part of the key space that is still
# covered. In order to do so, just set the cluster-require-full-coverage
# option to no.
#
# cluster-require-full-coverage yes
# This option, when set to yes, prevents replicas from trying to failover its
# master during master failures. However the replica can still perform a
# manual failover, if forced to do so.
#
# This is useful in different scenarios, especially in the case of multiple
# data center operations, where we want one side to never be promoted if not
# in the case of a total DC failure.
#
# cluster-replica-no-failover no
# This option, when set to yes, allows nodes to serve read traffic while the
# the cluster is in a down state, as long as it believes it owns the slots.
#
# This is useful for two cases. The first case is for when an application
# doesn't require consistency of data during node failures or network partitions.
# One example of this is a cache, where as long as the node has the data it
# should be able to serve it.
#
# The second use case is for configurations that don't meet the recommended
# three shards but want to enable cluster mode and scale later. A
# master outage in a 1 or 2 shard configuration causes a read/write outage to the
# entire cluster without this option set, with it set there is only a write outage.
# Without a quorum of masters, slot ownership will not change automatically.
#
# cluster-allow-reads-when-down no
# In order to setup your cluster make sure to read the documentation
# available at https://redis.io web site.
########################## CLUSTER DOCKER/NAT support ########################
# In certain deployments, Redis Cluster nodes address discovery fails, because
# addresses are NAT-ted or because ports are forwarded (the typical case is
# Docker and other containers).
#
# In order to make Redis Cluster working in such environments, a static
# configuration where each node knows its public address is needed. The
# following four options are used for this scope, and are:
#
# * cluster-announce-ip
# * cluster-announce-port
# * cluster-announce-tls-port
# * cluster-announce-bus-port
#
# Each instructs the node about its address, client ports (for connections
# without and with TLS) and cluster message bus port. The information is then
# published in the header of the bus packets so that other nodes will be able to
# correctly map the address of the node publishing the information.
#
# If cluster-tls is set to yes and cluster-announce-tls-port is omitted or set
# to zero, then cluster-announce-port refers to the TLS port. Note also that
# cluster-announce-tls-port has no effect if cluster-tls is set to no.
#
# If the above options are not used, the normal Redis Cluster auto-detection
# will be used instead.
#
# Note that when remapped, the bus port may not be at the fixed offset of
# clients port + 10000, so you can specify any port and bus-port depending
# on how they get remapped. If the bus-port is not set, a fixed offset of
# 10000 will be used as usual.
#
# Example:
#
# cluster-announce-ip 10.1.1.5
# cluster-announce-tls-port 6379
# cluster-announce-port 0
# cluster-announce-bus-port 6380
################################## SLOW LOG ###################################
# The Redis Slow Log is a system to log queries that exceeded a specified
# execution time. The execution time does not include the I/O operations
# like talking with the client, sending the reply and so forth,
# but just the time needed to actually execute the command (this is the only
# stage of command execution where the thread is blocked and can not serve
# other requests in the meantime).
#
# You can configure the slow log with two parameters: one tells Redis
# what is the execution time, in microseconds, to exceed in order for the
# command to get logged, and the other parameter is the length of the
# slow log. When a new command is logged the oldest one is removed from the
# queue of logged commands.
# The following time is expressed in microseconds, so 1000000 is equivalent
# to one second. Note that a negative number disables the slow log, while
# a value of zero forces the logging of every command.
slowlog-log-slower-than 10000
# There is no limit to this length. Just be aware that it will consume memory.
# You can reclaim memory used by the slow log with SLOWLOG RESET.
slowlog-max-len 128
################################ LATENCY MONITOR ##############################
# The Redis latency monitoring subsystem samples different operations
# at runtime in order to collect data related to possible sources of
# latency of a Redis instance.
#
# Via the LATENCY command this information is available to the user that can
# print graphs and obtain reports.
#
# The system only logs operations that were performed in a time equal or
# greater than the amount of milliseconds specified via the
# latency-monitor-threshold configuration directive. When its value is set
# to zero, the latency monitor is turned off.
#
# By default latency monitoring is disabled since it is mostly not needed
# if you don't have latency issues, and collecting data has a performance
# impact, that while very small, can be measured under big load. Latency
# monitoring can easily be enabled at runtime using the command
# "CONFIG SET latency-monitor-threshold <milliseconds>" if needed.
latency-monitor-threshold 0
############################# EVENT NOTIFICATION ##############################
# Redis can notify Pub/Sub clients about events happening in the key space.
# This feature is documented at https://redis.io/topics/notifications
#
# For instance if keyspace events notification is enabled, and a client
# performs a DEL operation on key "foo" stored in the Database 0, two
# messages will be published via Pub/Sub:
#
# PUBLISH __keyspace@0__:foo del
# PUBLISH __keyevent@0__:del foo
#
# It is possible to select the events that Redis will notify among a set
# of classes. Every class is identified by a single character:
#
# K Keyspace events, published with __keyspace@<db>__ prefix.
# E Keyevent events, published with __keyevent@<db>__ prefix.
# g Generic commands (non-type specific) like DEL, EXPIRE, RENAME, ...
# $ String commands
# l List commands
# s Set commands
# h Hash commands
# z Sorted set commands
# x Expired events (events generated every time a key expires)
# e Evicted events (events generated when a key is evicted for maxmemory)
# t Stream commands
# d Module key type events
# m Key-miss events (Note: It is not included in the 'A' class)
# A Alias for g$lshzxetd, so that the "AKE" string means all the events
# (Except key-miss events which are excluded from 'A' due to their
# unique nature).
#
# The "notify-keyspace-events" takes as argument a string that is composed
# of zero or multiple characters. The empty string means that notifications
# are disabled.
#
# Example: to enable list and generic events, from the point of view of the
# event name, use:
#
# notify-keyspace-events Elg
#
# Example 2: to get the stream of the expired keys subscribing to channel
# name __keyevent@0__:expired use:
#
# notify-keyspace-events Ex
#
# By default all notifications are disabled because most users don't need
# this feature and the feature has some overhead. Note that if you don't
# specify at least one of K or E, no events will be delivered.
notify-keyspace-events ""
############################### GOPHER SERVER #################################
# Redis contains an implementation of the Gopher protocol, as specified in
# the RFC 1436 (https://www.ietf.org/rfc/rfc1436.txt).
#
# The Gopher protocol was very popular in the late '90s. It is an alternative
# to the web, and the implementation both server and client side is so simple
# that the Redis server has just 100 lines of code in order to implement this
# support.
#
# What do you do with Gopher nowadays? Well Gopher never *really* died, and
# lately there is a movement in order for the Gopher more hierarchical content
# composed of just plain text documents to be resurrected. Some want a simpler
# internet, others believe that the mainstream internet became too much
# controlled, and it's cool to create an alternative space for people that
# want a bit of fresh air.
#
# Anyway for the 10nth birthday of the Redis, we gave it the Gopher protocol
# as a gift.
#
# --- HOW IT WORKS? ---
#
# The Redis Gopher support uses the inline protocol of Redis, and specifically
# two kind of inline requests that were anyway illegal: an empty request
# or any request that starts with "/" (there are no Redis commands starting
# with such a slash). Normal RESP2/RESP3 requests are completely out of the
# path of the Gopher protocol implementation and are served as usual as well.
#
# If you open a connection to Redis when Gopher is enabled and send it
# a string like "/foo", if there is a key named "/foo" it is served via the
# Gopher protocol.
#
# In order to create a real Gopher "hole" (the name of a Gopher site in Gopher
# talking), you likely need a script like the following:
#
# https://github.com/antirez/gopher2redis
#
# --- SECURITY WARNING ---
#
# If you plan to put Redis on the internet in a publicly accessible address
# to server Gopher pages MAKE SURE TO SET A PASSWORD to the instance.
# Once a password is set:
#
# 1. The Gopher server (when enabled, not by default) will still serve
# content via Gopher.
# 2. However other commands cannot be called before the client will
# authenticate.
#
# So use the 'requirepass' option to protect your instance.
#
# Note that Gopher is not currently supported when 'io-threads-do-reads'
# is enabled.
#
# To enable Gopher support, uncomment the following line and set the option
# from no (the default) to yes.
#
# gopher-enabled no
############################### ADVANCED CONFIG ###############################
# Hashes are encoded using a memory efficient data structure when they have a
# small number of entries, and the biggest entry does not exceed a given
# threshold. These thresholds can be configured using the following directives.
hash-max-ziplist-entries 512
hash-max-ziplist-value 64
# Lists are also encoded in a special way to save a lot of space.
# The number of entries allowed per internal list node can be specified
# as a fixed maximum size or a maximum number of elements.
# For a fixed maximum size, use -5 through -1, meaning:
# -5: max size: 64 Kb <-- not recommended for normal workloads
# -4: max size: 32 Kb <-- not recommended
# -3: max size: 16 Kb <-- probably not recommended
# -2: max size: 8 Kb <-- good
# -1: max size: 4 Kb <-- good
# Positive numbers mean store up to _exactly_ that number of elements
# per list node.
# The highest performing option is usually -2 (8 Kb size) or -1 (4 Kb size),
# but if your use case is unique, adjust the settings as necessary.
list-max-ziplist-size -2
# Lists may also be compressed.
# Compress depth is the number of quicklist ziplist nodes from *each* side of
# the list to *exclude* from compression. The head and tail of the list
# are always uncompressed for fast push/pop operations. Settings are:
# 0: disable all list compression
# 1: depth 1 means "don't start compressing until after 1 node into the list,
# going from either the head or tail"
# So: [head]->node->node->...->node->[tail]
# [head], [tail] will always be uncompressed; inner nodes will compress.
# 2: [head]->[next]->node->node->...->node->[prev]->[tail]
# 2 here means: don't compress head or head->next or tail->prev or tail,
# but compress all nodes between them.
# 3: [head]->[next]->[next]->node->node->...->node->[prev]->[prev]->[tail]
# etc.
list-compress-depth 0
# Sets have a special encoding in just one case: when a set is composed
# of just strings that happen to be integers in radix 10 in the range
# of 64 bit signed integers.
# The following configuration setting sets the limit in the size of the
# set in order to use this special memory saving encoding.
set-max-intset-entries 512
# Similarly to hashes and lists, sorted sets are also specially encoded in
# order to save a lot of space. This encoding is only used when the length and
# elements of a sorted set are below the following limits:
zset-max-ziplist-entries 128
zset-max-ziplist-value 64
# HyperLogLog sparse representation bytes limit. The limit includes the
# 16 bytes header. When an HyperLogLog using the sparse representation crosses
# this limit, it is converted into the dense representation.
#
# A value greater than 16000 is totally useless, since at that point the
# dense representation is more memory efficient.
#
# The suggested value is ~ 3000 in order to have the benefits of
# the space efficient encoding without slowing down too much PFADD,
# which is O(N) with the sparse encoding. The value can be raised to
# ~ 10000 when CPU is not a concern, but space is, and the data set is
# composed of many HyperLogLogs with cardinality in the 0 - 15000 range.
hll-sparse-max-bytes 3000
# Streams macro node max size / items. The stream data structure is a radix
# tree of big nodes that encode multiple items inside. Using this configuration
# it is possible to configure how big a single node can be in bytes, and the
# maximum number of items it may contain before switching to a new node when
# appending new stream entries. If any of the following settings are set to
# zero, the limit is ignored, so for instance it is possible to set just a
# max entries limit by setting max-bytes to 0 and max-entries to the desired
# value.
stream-node-max-bytes 4096
stream-node-max-entries 100
# Active rehashing uses 1 millisecond every 100 milliseconds of CPU time in
# order to help rehashing the main Redis hash table (the one mapping top-level
# keys to values). The hash table implementation Redis uses (see dict.c)
# performs a lazy rehashing: the more operation you run into a hash table
# that is rehashing, the more rehashing "steps" are performed, so if the
# server is idle the rehashing is never complete and some more memory is used
# by the hash table.
#
# The default is to use this millisecond 10 times every second in order to
# actively rehash the main dictionaries, freeing memory when possible.
#
# If unsure:
# use "activerehashing no" if you have hard latency requirements and it is
# not a good thing in your environment that Redis can reply from time to time
# to queries with 2 milliseconds delay.
#
# use "activerehashing yes" if you don't have such hard requirements but
# want to free memory asap when possible.
activerehashing yes
# The client output buffer limits can be used to force disconnection of clients
# that are not reading data from the server fast enough for some reason (a
# common reason is that a Pub/Sub client can't consume messages as fast as the
# publisher can produce them).
#
# The limit can be set differently for the three different classes of clients:
#
# normal -> normal clients including MONITOR clients
# replica -> replica clients
# pubsub -> clients subscribed to at least one pubsub channel or pattern
#
# The syntax of every client-output-buffer-limit directive is the following:
#
# client-output-buffer-limit <class> <hard limit> <soft limit> <soft seconds>
#
# A client is immediately disconnected once the hard limit is reached, or if
# the soft limit is reached and remains reached for the specified number of
# seconds (continuously).
# So for instance if the hard limit is 32 megabytes and the soft limit is
# 16 megabytes / 10 seconds, the client will get disconnected immediately
# if the size of the output buffers reach 32 megabytes, but will also get
# disconnected if the client reaches 16 megabytes and continuously overcomes
# the limit for 10 seconds.
#
# By default normal clients are not limited because they don't receive data
# without asking (in a push way), but just after a request, so only
# asynchronous clients may create a scenario where data is requested faster
# than it can read.
#
# Instead there is a default limit for pubsub and replica clients, since
# subscribers and replicas receive data in a push fashion.
#
# Both the hard or the soft limit can be disabled by setting them to zero.
client-output-buffer-limit normal 0 0 0
client-output-buffer-limit replica 256mb 64mb 60
client-output-buffer-limit pubsub 32mb 8mb 60
# Client query buffers accumulate new commands. They are limited to a fixed
# amount by default in order to avoid that a protocol desynchronization (for
# instance due to a bug in the client) will lead to unbound memory usage in
# the query buffer. However you can configure it here if you have very special
# needs, such us huge multi/exec requests or alike.
#
# client-query-buffer-limit 1gb
# In the Redis protocol, bulk requests, that are, elements representing single
# strings, are normally limited to 512 mb. However you can change this limit
# here, but must be 1mb or greater
#
# proto-max-bulk-len 512mb
# Redis calls an internal function to perform many background tasks, like
# closing connections of clients in timeout, purging expired keys that are
# never requested, and so forth.
#
# Not all tasks are performed with the same frequency, but Redis checks for
# tasks to perform according to the specified "hz" value.
#
# By default "hz" is set to 10. Raising the value will use more CPU when
# Redis is idle, but at the same time will make Redis more responsive when
# there are many keys expiring at the same time, and timeouts may be
# handled with more precision.
#
# The range is between 1 and 500, however a value over 100 is usually not
# a good idea. Most users should use the default of 10 and raise this up to
# 100 only in environments where very low latency is required.
hz 10
# Normally it is useful to have an HZ value which is proportional to the
# number of clients connected. This is useful in order, for instance, to
# avoid too many clients are processed for each background task invocation
# in order to avoid latency spikes.
#
# Since the default HZ value by default is conservatively set to 10, Redis
# offers, and enables by default, the ability to use an adaptive HZ value
# which will temporarily raise when there are many connected clients.
#
# When dynamic HZ is enabled, the actual configured HZ will be used
# as a baseline, but multiples of the configured HZ value will be actually
# used as needed once more clients are connected. In this way an idle
# instance will use very little CPU time while a busy instance will be
# more responsive.
dynamic-hz yes
# When a child rewrites the AOF file, if the following option is enabled
# the file will be fsync-ed every 32 MB of data generated. This is useful
# in order to commit the file to the disk more incrementally and avoid
# big latency spikes.
aof-rewrite-incremental-fsync yes
# When redis saves RDB file, if the following option is enabled
# the file will be fsync-ed every 32 MB of data generated. This is useful
# in order to commit the file to the disk more incrementally and avoid
# big latency spikes.
rdb-save-incremental-fsync yes
# Redis LFU eviction (see maxmemory setting) can be tuned. However it is a good
# idea to start with the default settings and only change them after investigating
# how to improve the performances and how the keys LFU change over time, which
# is possible to inspect via the OBJECT FREQ command.
#
# There are two tunable parameters in the Redis LFU implementation: the
# counter logarithm factor and the counter decay time. It is important to
# understand what the two parameters mean before changing them.
#
# The LFU counter is just 8 bits per key, it's maximum value is 255, so Redis
# uses a probabilistic increment with logarithmic behavior. Given the value
# of the old counter, when a key is accessed, the counter is incremented in
# this way:
#
# 1. A random number R between 0 and 1 is extracted.
# 2. A probability P is calculated as 1/(old_value*lfu_log_factor+1).
# 3. The counter is incremented only if R < P.
#
# The default lfu-log-factor is 10. This is a table of how the frequency
# counter changes with a different number of accesses with different
# logarithmic factors:
#
# +--------+------------+------------+------------+------------+------------+
# | factor | 100 hits | 1000 hits | 100K hits | 1M hits | 10M hits |
# +--------+------------+------------+------------+------------+------------+
# | 0 | 104 | 255 | 255 | 255 | 255 |
# +--------+------------+------------+------------+------------+------------+
# | 1 | 18 | 49 | 255 | 255 | 255 |
# +--------+------------+------------+------------+------------+------------+
# | 10 | 10 | 18 | 142 | 255 | 255 |
# +--------+------------+------------+------------+------------+------------+
# | 100 | 8 | 11 | 49 | 143 | 255 |
# +--------+------------+------------+------------+------------+------------+
#
# NOTE: The above table was obtained by running the following commands:
#
# redis-benchmark -n 1000000 incr foo
# redis-cli object freq foo
#
# NOTE 2: The counter initial value is 5 in order to give new objects a chance
# to accumulate hits.
#
# The counter decay time is the time, in minutes, that must elapse in order
# for the key counter to be divided by two (or decremented if it has a value
# less <= 10).
#
# The default value for the lfu-decay-time is 1. A special value of 0 means to
# decay the counter every time it happens to be scanned.
#
# lfu-log-factor 10
# lfu-decay-time 1
########################### ACTIVE DEFRAGMENTATION #######################
#
# What is active defragmentation?
# -------------------------------
#
# Active (online) defragmentation allows a Redis server to compact the
# spaces left between small allocations and deallocations of data in memory,
# thus allowing to reclaim back memory.
#
# Fragmentation is a natural process that happens with every allocator (but
# less so with Jemalloc, fortunately) and certain workloads. Normally a server
# restart is needed in order to lower the fragmentation, or at least to flush
# away all the data and create it again. However thanks to this feature
# implemented by Oran Agra for Redis 4.0 this process can happen at runtime
# in a "hot" way, while the server is running.
#
# Basically when the fragmentation is over a certain level (see the
# configuration options below) Redis will start to create new copies of the
# values in contiguous memory regions by exploiting certain specific Jemalloc
# features (in order to understand if an allocation is causing fragmentation
# and to allocate it in a better place), and at the same time, will release the
# old copies of the data. This process, repeated incrementally for all the keys
# will cause the fragmentation to drop back to normal values.
#
# Important things to understand:
#
# 1. This feature is disabled by default, and only works if you compiled Redis
# to use the copy of Jemalloc we ship with the source code of Redis.
# This is the default with Linux builds.
#
# 2. You never need to enable this feature if you don't have fragmentation
# issues.
#
# 3. Once you experience fragmentation, you can enable this feature when
# needed with the command "CONFIG SET activedefrag yes".
#
# The configuration parameters are able to fine tune the behavior of the
# defragmentation process. If you are not sure about what they mean it is
# a good idea to leave the defaults untouched.
# Enabled active defragmentation
# activedefrag no
# Minimum amount of fragmentation waste to start active defrag
# active-defrag-ignore-bytes 100mb
# Minimum percentage of fragmentation to start active defrag
# active-defrag-threshold-lower 10
# Maximum percentage of fragmentation at which we use maximum effort
# active-defrag-threshold-upper 100
# Minimal effort for defrag in CPU percentage, to be used when the lower
# threshold is reached
# active-defrag-cycle-min 1
# Maximal effort for defrag in CPU percentage, to be used when the upper
# threshold is reached
# active-defrag-cycle-max 25
# Maximum number of set/hash/zset/list fields that will be processed from
# the main dictionary scan
# active-defrag-max-scan-fields 1000
# Jemalloc background thread for purging will be enabled by default
jemalloc-bg-thread yes
# It is possible to pin different threads and processes of Redis to specific
# CPUs in your system, in order to maximize the performances of the server.
# This is useful both in order to pin different Redis threads in different
# CPUs, but also in order to make sure that multiple Redis instances running
# in the same host will be pinned to different CPUs.
#
# Normally you can do this using the "taskset" command, however it is also
# possible to this via Redis configuration directly, both in Linux and FreeBSD.
#
# You can pin the server/IO threads, bio threads, aof rewrite child process, and
# the bgsave child process. The syntax to specify the cpu list is the same as
# the taskset command:
#
# Set redis server/io threads to cpu affinity 0,2,4,6:
# server_cpulist 0-7:2
#
# Set bio threads to cpu affinity 1,3:
# bio_cpulist 1,3
#
# Set aof rewrite child process to cpu affinity 8,9,10,11:
# aof_rewrite_cpulist 8-11
#
# Set bgsave child process to cpu affinity 1,10,11
# bgsave_cpulist 1,10-11
# In some cases redis will emit warnings and even refuse to start if it detects
# that the system is in bad state, it is possible to suppress these warnings
# by setting the following config which takes a space delimited list of warnings
# to suppress
#
# ignore-warnings ARM64-COW-BUG
Redist持久化
redis属于内存数据库，如果不保存那么根据内存的特性，断电就不存在，所以对应持久化是非常重要的。 redis的持久化主要有两种方式，rdb（Redis DataBase） 和 aof（Append Only File）
rdb
rdb 持久化方式主要是保存redis 中存储的数据。
RDB持久化过程分为手动触发和自动触发
手动触发：
手动触发分别对应save和bgsave命令
save：阻塞当前Redis服务器，直到RDB过程完成为止，对于内存 比较大的实例会造成长时间阻塞，线上环境不建议使用
bgsave：Redis进程执行fork操作创建子进程，RDB持久化过程由子进程负责，完成后自动结束。阻塞只发生在fork阶段，一般时间很短。
自动触发：
1、按照配置文件中所配置的 save m n 的规则自动触发。
2、如果从节点执行全量复制操作，主节点自动执行bgsave生成RDB文件并发送给从节点。
3、执行debug reload命令重新加载Redis时，也会自动触发save操作。
4、执行shutdown命令时，如果没有开启AOF持久化功能则自动执行bgsave。
rdb的相关配置在，配置文件中的SNAPSHOTTING 中
由于 rdb 的保存文件属于间断性保存，在运行的过程中，如果突然宕机，那么它保存的文件只能是之前一次保存的数据。
优点，恢复数据快，适合大规模数据恢复，缺点 对数据的保存不完善，容易丢失小部分数据
aof
aof持久化方式，主要是记录对 redis的 写和修改的操作，在恢复时，将就记录的命令再次执行一次
aof的主要作用 是解决了数据持久化的实时性，目前已经是Redis持久化的主流方式
aof 的相关配置在 APPEND ONLY MODE，具体如下
Redis订阅模式
类似于消息队列的订阅模式，不做具体讲解，我们看看用法即可
Redis 发布订阅 (pub/sub) 是一种消息通信模式：发送者 (pub) 发送消息，订阅者 (sub) 接收消息。
Redis 客户端可以订阅任意数量的频道。
订阅需要订阅的频道，类似于关注微信众号
127.0.0.1:6379> SUBSCRIBE wyx
Reading messages... (press Ctrl-C to quit)
1) "subscribe"
2) "wyx"
3) (integer) 1
订阅频道发送消息
127.0.0.1:6379> PUBLISH wyx "Redis PUBLISH test"
(integer) 1
查看订阅者，已经收到消息
退订频道，取消关注
# 可以同时退订多个值，空格隔开即可
UNSUBSCRIBE wyz
Redis主从复制原理
概述
主从复制，是指将一台Redis服务器的数据，复制到其他的Redis服务器。前者称为主节点(master)，后者称为 从节点(slave)；数据的复制是单向的，只能由主节点到从节点。
默认情况下，每台Redis服务器都是主节点；且一个主节点可以有多个从节点(或没有从节点)，但一个从节点只能有一个主节点。
主从复制的作用
主从复制的作用主要包括：
数据冗余：主从复制实现了数据的热备份，是持久化之外的一种数据冗余方式。故障恢复：当主节点出现问题时，可以由从节点提供服务，实现快速的故障恢复；实际上是一种服务的冗余。负载均衡：在主从复制的基础上，配合读写分离，可以由主节点提供写服务，由从节点提供读服务（即写Redis数据时应用连接主节点，读Redis数据时应用连接从节点），分担服务器负载；尤其是在写少读多的场景下，通过多个从节点分担读负载，可以大大提高Redis服务器的并发量。高可用：除了上述作用以外，主从复制还是哨兵和集群能够实施的基础，因此说主从复制是Redis高可用的基础。
集群模式
一主多从
一主一从(链式)
集群的方式主要有两种配置文件，和使用命令集群，
但是使用命令的集群方式，下一次重新连接，会变会主机，一般不使用，使用配置文件的方式，但是如果主机宕机了，没有主机也会出现问题，配置文件一般都是结合哨兵模式进行使用，后面讲解
首先我们准备3台安装Redis 的虚拟机，
在Redis中主从复制，使用命令方法，就只需要一个配置，就是认主机
# 命令
slaveod 主机IP 端口号
# 查看属于什么节点可以使用
info replication
测试：启动三台虚拟机的redis-server ，并使用客户端连接后，执行info replication 查看自己的信息，都是master
使用slaveod 主机IP 端口号，将其中两台通过认主机的方式查看具体信息
# 示例
127.0.0.1:6379> SLAVEOF 192.168.137.129 6379
OK
再次查看主机的信息
查看从机信息
在从机上执行写操作
# 不能执行，因为redis 规则默认为主从复制，读写分离，master 写 （slave 只能读）
127.0.0.1:6379> set k2 v2
(error) READONLY You can't write against a read only replica.
# 所有如果主机宕机后，redis的写操作将不可用，会变得非常危险，
# 我们可以通过 slaveod no one 让 slave 成为主机，但是必须手动（非常麻烦）
复制原理
slave 连接 master 会发送同步命令
master接收到命令后，会将自身的数据文件同步到slave中完成一次完全同步
第一次连接时，一般都会全量复制，后续都是增量复制
全量配置：全部数据进行一次复制
增量复制：将master新的到的值，复制给slave
注意点：master主机一般都是只写不读，slave是只读不写，执行写命令时报错
如果主机断开连接，我们可以使用命令，让自己成为主机
# 让自己变成主机（手动）
slaveod no one
Redis哨兵模式
在上面的主从复制，我们介绍了可以使用命令slaveod 主机IP 端口号 来确定主从，我们也可以使用配置文件来配置(为讲解)，但是都有问题，使用手动模式，每次都需要认主机，使用配置文件也可以实现，但是主节点宕机后，将要平凡的修改配置文件，将会严重的影响工作效率，下面我们来介绍一种可以自动配置主节点，和从节点的一种模式。哨兵模式
哨兵模式原理图：
哨兵模式概述：
哨兵：在一定时间间隔类，向Redis发送命令，并等待回复，如果有回复，则认为服务器正常。（同时监测多个Redis）
多哨兵：如果启动哨兵的服务器宕机，其他节点跟随宕机，也会造成不可以，所以引入多哨兵互相监督。
工作流程：在服务启动后每个哨兵会向其他哨兵和Redis服务器发送消息并等待回复。如果监测到某个哨兵或者Redis服务器没有回复，则哨兵会请求其他哨兵也发送请求再次确认，在多个哨兵的确认下，如果都没有回复，则认为服务器或哨兵已经宕机，如果宕机的是Master节点，那么哨兵和哨兵之间会进行投票选举出新的Master，当以前的Master再次上线时，作为slave 使用，这样的设计思路，解决了我们在主从复制中需要手动改变主机。提高使用效率。
哨兵模式搭建
修改三台服务器的redis.conf配置文件
# 使得Redis服务器可以跨网络访问
bind 0.0.0.0
# 设置密码
requirepass "123456"
# 指定主服务器，注意：有关slaveof的配置只是配置从服务器，主服务器不需要配置(master不用配置)
slaveof 192.168.137.129 6379
# 主服务器密码，注意：有关slaveof的配置只是配置从服务器，主服务器不需要配置(master不用配置)
masterauth 123456
master
slave
编辑启动哨兵的配置文件sentinel.conf（3个都需要配置）
# 在安装的目录下找到sentinel.conf文件，并复制到启动目录的redisconf
cp /opt/redis-6.2.2/sentinel.conf /usr/local/bin/redisconf/
编辑移动后的配置文件
vim /usr/local/bin/redisconf/sentinel.conf
# 添加以下内容
# 禁止保护模式
protected-mode no
# 配置监听的主服务器，这里sentinel monitor代表监控，mymaster代表服务器的名称，可以自定义，192.168.11.128代表监控的主服务器，6379代表端口，2代表只有两个或两个以上的哨兵认为主服务器不可用的时候，才会进行failover操作。
sentinel monitor mymaster 192.168.137.129 6379 2
sentinel monitor myslave1 192.168.137.130 6379 2
sentinel monitor myslave2 192.168.137.131 6379 2
# sentinel author-pass定义服务的密码，mymaster是服务名称，123456是Redis服务器密码
# sentinel auth-pass <master-name> <password>
sentinel auth-pass mymaster 123456
sentinel auth-pass myslave1 123456
sentinel auth-pass myslave2 123456
# 注意禁用它自己配置的默认监控
哨兵的更多配置文件详解sentinel.conf
# Example sentinel.conf
# 哨兵sentinel实例运行的端口 默认26379
port 26379
# 哨兵sentinel的工作目录
dir /tmp
# 哨兵sentinel监控的redis主节点的 ip port
# master-name 可以自己命名的主节点名字 只能由字母A-z、数字0-9 、这三个字符".-_"组成。
# quorum 当这些quorum个数sentinel哨兵认为master主节点失联 那么这时 客观上认为主节点失联了
# sentinel monitor <master-name> <ip> <redis-port> <quorum>
sentinel monitor mymaster 127.0.0.1 6379 2
# 当在Redis实例中开启了requirepass foobared 授权密码 这样所有连接Redis实例的客户端都要提供密码
# 设置哨兵sentinel 连接主从的密码 注意必须为主从设置一样的验证密码
# sentinel auth-pass <master-name> <password>
sentinel auth-pass mymaster MySUPER--secret-0123passw0rd
# 指定多少毫秒之后 主节点没有应答哨兵sentinel 此时 哨兵主观上认为主节点下线 默认30秒
# sentinel down-after-milliseconds <master-name> <milliseconds>
sentinel down-after-milliseconds mymaster 30000
# 这个配置项指定了在发生failover主备切换时最多可以有多少个slave同时对新的master进行 同步，
这个数字越小，完成failover所需的时间就越长，
但是如果这个数字越大，就意味着越 多的slave因为replication而不可用。
可以通过将这个值设为 1 来保证每次只有一个slave 处于不能处理命令请求的状态。
# sentinel parallel-syncs <master-name> <numslaves>
sentinel parallel-syncs mymaster 1
# 故障转移的超时时间 failover-timeout 可以用在以下这些方面：
#1. 同一个sentinel对同一个master两次failover之间的间隔时间。
#2. 当一个slave从一个错误的master那里同步数据开始计算时间。直到slave被纠正为向正确的master那里同步数据时。
#3.当想要取消一个正在进行的failover所需要的时间。
#4.当进行failover时，配置所有slaves指向新的master所需的最大时间。不过，即使过了这个超时，slaves依然会被正确配置为指向master，但是就不按parallel-syncs所配置的规则来了
# 默认三分钟
# sentinel failover-timeout <master-name> <milliseconds>
sentinel failover-timeout mymaster 180000
# SCRIPTS EXECUTION
#配置当某一事件发生时所需要执行的脚本，可以通过脚本来通知管理员，例如当系统运行不正常时发邮件通知相关人员。
#对于脚本的运行结果有以下规则：
#若脚本执行后返回1，那么该脚本稍后将会被再次执行，重复次数目前默认为10
#若脚本执行后返回2，或者比2更高的一个返回值，脚本将不会重复执行。
#如果脚本在执行过程中由于收到系统中断信号被终止了，则同返回值为1时的行为相同。
#一个脚本的最大执行时间为60s，如果超过这个时间，脚本将会被一个SIGKILL信号终止，之后重新执行。
#通知型脚本:当sentinel有任何警告级别的事件发生时（比如说redis实例的主观失效和客观失效等等），将会去调用这个脚本，这时这个脚本应该通过邮件，SMS等方式去通知系统管理员关于系统不正常运行的信息。调用该脚本时，将传给脚本两个参数， 一个是事件的类型， 一个是事件的描述。如果sentinel.conf配置文件中配置了这个脚本路径，那么必须保证这个脚本存在于这个路径，并且是可执行的，否则sentinel无法正常启动成功。
#通知脚本
# sentinel notification-script <master-name> <script-path>
sentinel notification-script mymaster /var/redis/notify.sh
# 客户端重新配置主节点参数脚本
# 当一个master由于failover而发生改变时，这个脚本将会被调用，通知相关的客户端关于master地址已经发生改变的信息。
# 以下参数将会在调用脚本时传给脚本:
# <master-name> <role> <state> <from-ip> <from-port> <to-ip> <to-port>
# 目前<state>总是“failover”,
# <role>是“leader”或者“observer”中的一个。
# 参数 from-ip, from-port, to-ip, to-port是用来和旧的master和新的master(即旧的slave)通信的
# 这个脚本应该是通用的，能被多次调用，不是针对性的。
# sentinel client-reconfig-script <master-name> <script-path>
sentinel client-reconfig-script mymaster /var/redis/reconfig.sh
测试启动：首先是主机的Redis服务进程，然后启动从机的服务进程，最后启动3个哨兵的服务进程。
# 启动Redis服务器进程
./redis-server ../redis.conf
# 启动哨兵进程
./redis-sentinel ../sentinel.conf
我们查看主机的启动信息
[root@localhost bin]# redis-cli -p 6379
127.0.0.1:6379>
127.0.0.1:6379> auth 123456 # 密码登录，刚刚配置文件中设置了密码
ok
故意断开主机去从机测试再次测试
master连接后再次查看信息
至此：搭建完成
