redis-cli 命令详解
redis-cli 命令详解
redis-cli命令使用
命令使用
redis-cli [OPTIONS] [cmd [arg [arg ...]]]
选项说明
-h <hostname> Server hostname (default: 127.0.0.1). ip地址
-p <port> Server port (default: 6379). 服务器端口号
-s <socket> Server socket (overrides hostname and port).
-a <password> Password to use when connecting to the server. 密码
-u <uri> Server URI. url格式的地址
-r <repeat> Execute specified command N times.
-i <interval> When -r is used, waits <interval> seconds per command.
It is possible to specify sub-second times like -i 0.1.
-n <db> Database number. 指定数据库
-x Read last argument from STDIN.
-d <delimiter> Multi-bulk delimiter in for raw formatting (default: \n).
-c Enable cluster mode (follow -ASK and -MOVED redirections).
--raw Use raw formatting for replies (default when STDOUT is
not a tty).
--no-raw Force formatted output even when STDOUT is not a tty.
--csv Output in CSV format.
--stat Print rolling stats about server: mem, clients, ... 统计数据 连续输出
--latency Enter a special mode continuously sampling latency.
If you use this mode in an interactive session it runs
forever displaying real-time stats. Otherwise if --raw or
--csv is specified, or if you redirect the output to a non
TTY, it samples the latency for 1 second (you can use
-i to change the interval), then produces a single output
and exits. 延时统计
--latency-history Like --latency but tracking latency changes over time.
Default time interval is 15 sec. Change it using -i.
--latency-dist Shows latency as a spectrum, requires xterm 256 colors.
Default time interval is 1 sec. Change it using -i.
--lru-test <keys> Simulate a cache workload with an 80-20 distribution.
--replica Simulate a replica showing commands received from the master.
--rdb <filename> Transfer an RDB dump from remote server to local file. 导出rdb文件
--pipe Transfer raw Redis protocol from stdin to server.
管道模式
--pipe-timeout <n> In --pipe mode, abort with error if after sending all data.
no reply is received within <n> seconds.
Default timeout: 30. Use 0 to wait forever.
管道超时
--bigkeys Sample Redis keys looking for big keys.
--hotkeys Sample Redis keys looking for hot keys.
only works when maxmemory-policy is *lfu.
--scan List all keys using the SCAN command.获取服务器所有的键
--pattern <pat> Useful with --scan to specify a SCAN pattern.
正则表达式 用于scan命令中
--intrinsic-latency <sec> Run a test to measure intrinsic system latency.
The test will run for the specified amount of seconds.
--eval <file> Send an EVAL command using the Lua script at <file>.
--ldb Used with --eval enable the Redis Lua debugger.
--ldb-sync-mode Like --ldb but uses the synchronous Lua debugger, in
this mode the server is blocked and script changes are
not rolled back from the server memory.
--cluster <command> [args...] [opts...]
Cluster Manager command and arguments (see below).
--verbose Verbose mode.
--no-auth-warning Don't show warning message when using password on command
line interface.
注意：
- -u选项中url格式参考文档https://www.iana.org/assignments/uri-schemes/prov/redis 格式为：redis://user:secret@localhost:6379/0?foo=bar&qux=baz
举例：
例子１：
root@hylaz:~# redis-cli
127.0.0.1:6379> set name hylaz
OK
127.0.0.1:6379> quit
root@hylaz:~# redis-cli -h 127.0.0.1
127.0.0.1:6379> get name
"hylaz"
127.0.0.1:6379> quit
root@hylaz:~# redis-cli -h 127.0.0.1 -p 6379
127.0.0.1:6379> set age 20
OK
127.0.0.1:6379> get age
"20"
127.0.0.1:6379> quit
root@hylaz:~# redis-cli -h 127.0.0.1 -p 6379 -n 2
127.0.0.1:6379[2]> get age
(nil)
127.0.0.1:6379[2]> set age 23
OK
127.0.0.1:6379[2]> get age
"23"
127.0.0.1:6379[2]> quit
例子２：
server中统计选项
root@hylaz:~# redis-cli --stat
------- data ------ --------------------- load -------------------- - child -
keys mem clients blocked requests connections
11 835.52K 1 0 12 (+0) 5
11 835.52K 1 0 13 (+1) 5
11 835.52K 1 0 14 (+1) 5
11 835.52K 1 0 15 (+1) 5
列表中选项说明：
| 选项 | 含义 |
|---|---|
| keys | server中key的数量 |
| mem | 键值对的总内存量 |
| clients | 当前连接的总clients数量 |
| blocked | 当前阻塞的客户端数量 |
| requests | 服务器请求总次数 (+1) 截止上次请求增加次数 |
| connections | 服务器连接次数 |
使用info命令获取服务器的信息
例子３：
导入rdb文件 命令：redis-cli --rdb rdb.log
root@hylaz:~# redis-cli --rdb rdb.log
SYNC sent to master, writing 344 bytes to 'rdb.log'
Transfer finished with success.
该命令选项实现：
- 向server发送SYNC命令，返回需要写的总字节数
- 从server读取总字节数据写到指定文件中
例子４：
找出各种数据类型的最大键值对 命令：redis-cli --big-keys
root@hylaz:~# redis-cli --bigkeys
# Scanning the entire keyspace to find biggest keys as well as
# average sizes per key type. You can use -i 0.1 to sleep 0.1 sec
# per 100 SCAN commands (not usually needed).
[00.00%] Biggest string found so far 'name1' with 5 bytes
[00.00%] Biggest set found so far 'myset' with 1 members
[00.00%] Biggest string found so far 'key' with 6 bytes
-------- summary -------
Sampled 13 keys in the keyspace!
Total key length in bytes is 52 (avg len 4.00)
Biggest string found 'key' has 6 bytes
Biggest set found 'myset' has 1 members
12 strings with 33 bytes (92.31% of keys, avg size 2.75)
0 lists with 0 items (00.00% of keys, avg size 0.00)
1 sets with 1 members (07.69% of keys, avg size 1.00)
0 hashs with 0 fields (00.00% of keys, avg size 0.00)
0 zsets with 0 members (00.00% of keys, avg size 0.00)
0 streams with 0 entries (00.00% of keys, avg size 0.00)
该选项实现：通过使用scan命令遍历server中的键值对，针对不同数据类型进行统计，
例子５：
找出server中热点key 命令：redis-cli --hotkeys
# Scanning the entire keyspace to find hot keys as well as
# average sizes per key type. You can use -i 0.1 to sleep 0.1 sec
# per 100 SCAN commands (not usually needed).
[00.00%] Hot key 'dd' found so far with counter 4
[00.00%] Hot key 'myset' found so far with counter 5
[00.00%] Hot key 'a' found so far with counter 5
[00.00%] Hot key 'dds' found so far with counter 4
[71.43%] Hot key 'aa' found so far with counter 4
[71.43%] Hot key 'key' found so far with counter 4
-------- summary -------
Sampled 14 keys in the keyspace!
hot key found with counter: 5 keyname: myset
hot key found with counter: 5 keyname: a
hot key found with counter: 4 keyname: dd
hot key found with counter: 4 keyname: dds
hot key found with counter: 4 keyname: aa
hot key found with counter: 4 keyname: key
选项实现：
-
redis实现8种缓存淘汰策略：
voltile-lru：从已设置过期时间的数据集（server.db[i].expires）中挑选最近最少使用的数据淘汰
volatile-ttl：从已设置过期时间的数据集（server.db[i].expires）中挑选将要过期的数据淘汰
volatile-random：从已设置过期时间的数据集（server.db[i].expires）中任意选择数据淘汰
volatile-lfu: 从已设置过期时间的数据集驱逐使用频率最少的键
allkeys-lru:从数据集（server.db[i].dict）中挑选最近最少使用的数据淘汰
allkeys-lfu: 从所有键中驱逐使用频率最少的键
allkeys-random：从数据集（server.db[i].dict）中任意选择数据淘汰
no-enviction（驱逐）：禁止驱逐数据 当内存不足以容纳新写入数据时，新写入操作会报错
需要设置淘汰策略为lru或者lfu
２．命令实现使用scan命令遍历所有的键值对，针对每个键值对使用OBJECT freq 获取该键值对的信息
