Python就业班——Redis数据库
1、redis参数配置(redis.windows.conf)
# Redis configuration file example # 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: # # 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. ################################## 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. # # Notice 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. # # include .\path\to\local.conf # include c:\path\to\other.conf ################################## NETWORK ##################################### # By default, if no "bind" configuration directive is specified, Redis listens # for connections from all the network interfaces available on the server. # It is possible to listen to just one or multiple selected interfaces using # the "bind" configuration directive, followed by one or more IP addresses. # # Examples: # # bind 192.168.1.100 10.0.0.1 # bind 127.0.0.1 ::1 # # ~~~ 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 into # the IPv4 lookback interface address (this means Redis will be able to # accept connections only from clients running into the same computer it # is running). # # IF YOU ARE SURE YOU WANT YOUR INSTANCE TO LISTEN TO ALL THE INTERFACES # JUST COMMENT THE FOLLOWING LINE. # ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ # 允许的IP,默认只允许本机访问——lgsp_Harold-Hua # bind 127.0.0.1 bind 0.0.0.0 # 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. 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. # 端口号,默认6379——lgsp_Harold-Hua port 6379 # TCP listen() backlog. # # In high requests-per-second environments you need an high backlog in order # to avoid slow clients connections 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. 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 /tmp/redis.sock # unixsocketperm 700 # Close the connection after a client is idle for N seconds (0 to disable) # client空闲多少秒后关闭连接,默认0代表无限制——lgsp_Harold-Hua # timeout 0 timeout 300 # 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) Take the connection alive from the point of view of network # equipment in the middle. # # 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 60 seconds. tcp-keepalive 0 ################################# 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. # NOT SUPPORTED ON WINDOWS daemonize no # 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 # supervised systemd - signal systemd by writing READY=1 to $NOTIFY_SOCKET # 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 liveness pings back to your supervisor. # NOT SUPPORTED ON WINDOWS supervised no # 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. # NOT SUPPORTED ON WINDOWS pidfile /var/run/redis.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) # 日志级别——lgsp_Harold-Hua loglevel notice # Specify the log file name. Also 'stdout' can be used to force # Redis to log on the standard output. # 日志文件地址——lgsp_Harold-Hua # logfile "" logfile "logs.log" # To enable logging to the Windows EventLog, just set 'syslog-enabled' to # yes, and optionally update the other syslog parameters to suit your needs. # If Redis is installed and launched as a Windows Service, this will # automatically be enabled. # 把日志记录到系统日志,默认yes——lgsp_Harold-Hua # syslog-enabled no syslog-enabled no # Specify the source name of the events in the Windows Application log. # syslog-ident redis # 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 # 逻辑库数量,默认16——lgsp_Harold-Hua # databases 16 databases 9 ################################ SNAPSHOTTING ################################ # # Save the DB on disk: # # save <seconds> <changes> # # Will save the DB if both the given number of seconds and the given # number of write operations against the DB occurred. # # In the example below the behaviour will be to save: # after 900 sec (15 min) if at least 1 key changed # after 300 sec (5 min) if at least 10 keys changed # after 60 sec if at least 10000 keys changed # # Note: you can disable saving completely by commenting out all "save" lines. # # It is also possible to remove all the previously configured save # points by adding a save directive with a single empty string argument # like in the following example: # # save "" # RDB文件同步频率——lgsp_Harold-Hua # 注释掉,开启AOF方式 # save 900 1 # save 300 10 # 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. stop-writes-on-bgsave-error yes # Compress string objects using LZF when dump .rdb databases? # For default that's set to 'yes' 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. # 同步RDB文件的时候是否采用压缩,默认yes——lgsp_Harold-Hua 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. rdbchecksum yes # The filename where to dump the DB # 镜像文件名称,默认dump.rdb——lgsp_Harold-Hua dbfilename dump.rdb # 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文件的目录,默认redis目录——lgsp_Harold-Hua dir ./ ################################# REPLICATION ################################# # Master-Slave replication. Use slaveof to make a Redis instance a copy of # another Redis server. A few things to understand ASAP about Redis replication. # # 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 slaves. # 2) Redis slaves 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 slaves automatically try to reconnect to masters # and resynchronize with them. # # slaveof <masterip> <masterport> # If the master is password protected (using the "requirepass" configuration # directive below) it is possible to tell the slave to authenticate before # starting the replication synchronization process, otherwise the master will # refuse the slave request. # # masterauth <master-password> # When a slave loses its connection with the master, or when the replication # is still in progress, the slave can act in two different ways: # # 1) if slave-serve-stale-data is set to 'yes' (the default) the slave 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 slave-serve-stale-data is set to 'no' the slave will reply with # an error "SYNC with master in progress" to all the kind of commands # but to INFO and SLAVEOF. # slave-serve-stale-data yes # You can configure a slave instance to accept writes or not. Writing against # a slave instance may be useful to store some ephemeral data (because data # written on a slave 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 slaves are read-only. # # Note: read only slaves 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 slave 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 slaves using 'rename-command' to shadow all the # administrative / dangerous commands. slave-read-only yes # Replication SYNC strategy: disk or socket. # # ------------------------------------------------------- # WARNING: DISKLESS REPLICATION IS EXPERIMENTAL CURRENTLY # ------------------------------------------------------- # # New slaves and reconnecting slaves 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 slaves. # 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 slaves incrementally. # 2) Diskless: The Redis master creates a new process that directly writes the # RDB file to slave sockets, without touching the disk at all. # # With disk-backed replication, while the RDB file is generated, more slaves # 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 slaves 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 slaves # 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 slaves. # # This is important since once the transfer starts, it is not possible to serve # new slaves arriving, that will be queued for the next RDB transfer, so the server # waits a delay in order to let more slaves 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 # Slaves send PINGs to server in a predefined interval. It's possible to change # this interval with the repl_ping_slave_period option. The default value is 10 # seconds. # # repl-ping-slave-period 10 # The following option sets the replication timeout for: # # 1) Bulk transfer I/O during SYNC, from the point of view of slave. # 2) Master timeout from the point of view of slaves (data, pings). # 3) Slave 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-slave-period otherwise a timeout will be detected # every time there is low traffic between the master and the slave. # # repl-timeout 60 # Disable TCP_NODELAY on the slave socket after SYNC? # # If you select "yes" Redis will use a smaller number of TCP packets and # less bandwidth to send data to slaves. But this can add a delay for # the data to appear on the slave side, up to 40 milliseconds with # Linux kernels using a default configuration. # # If you select "no" the delay for data to appear on the slave 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 slaves 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 # slave data when slaves are disconnected for some time, so that when a slave # wants to reconnect again, often a full resync is not needed, but a partial # resync is enough, just passing the portion of data the slave missed while # disconnected. # # The bigger the replication backlog, the longer the time the slave can be # disconnected and later be able to perform a partial resynchronization. # # The backlog is only allocated once there is at least a slave connected. # # repl-backlog-size 1mb # After a master has no longer connected slaves 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 slave disconnected, for # the backlog buffer to be freed. # # A value of 0 means to never release the backlog. # # repl-backlog-ttl 3600 # The slave priority is an integer number published by Redis in the INFO output. # It is used by Redis Sentinel in order to select a slave to promote into a # master if the master is no longer working correctly. # # A slave with a low priority number is considered better for promotion, so # for instance if there are three slaves 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 slave as not able to perform the # role of master, so a slave with priority of 0 will never be selected by # Redis Sentinel for promotion. # # By default the priority is 100. slave-priority 100 # It is possible for a master to stop accepting writes if there are less than # N slaves connected, having a lag less or equal than M seconds. # # The N slaves 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 slave, 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 slaves # are available, to the specified number of seconds. # # For example to require at least 3 slaves with a lag <= 10 seconds use: # # min-slaves-to-write 3 # min-slaves-max-lag 10 # # Setting one or the other to 0 disables the feature. # # By default min-slaves-to-write is set to 0 (feature disabled) and # min-slaves-max-lag is set to 10. ################################## SECURITY ################################### # Require clients to issue AUTH <PASSWORD> before processing any other # commands. This might be useful in environments in which you do not trust # others with access to the host running redis-server. # # This should stay commented out for backward compatibility and because most # people do not need auth (e.g. they run their own servers). # # Warning: since Redis is pretty fast an outside user can try up to # 150k passwords per second against a good box. This means that you should # use a very strong password otherwise it will be very easy to break. # # 设置redis访问密码,默认无需密码——lgsp_Harold-Hua # requirepass foobared requirepass root # Command renaming. # # 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 slaves may cause problems. ################################### LIMITS #################################### # 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'. # # 最大连接数,默认无限制——lgsp_Harold-Hua # maxclients 10000 maxclients 2000 # If Redis is to be used as an in-memory-only cache without any kind of # persistence, then the fork() mechanism used by the background AOF/RDB # persistence is unnecessary. As an optimization, all persistence can be # turned off in the Windows version of Redis. This will redirect heap # allocations to the system heap allocator, and disable commands that would # otherwise cause fork() operations: BGSAVE and BGREWRITEAOF. # This flag may not be combined with any of the other flags that configure # AOF and RDB operations. # persistence-available [(yes)|no] # Don't use more memory than 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 cache, or to set # a hard memory limit for an instance (using the 'noeviction' policy). # # WARNING: If you have slaves attached to an instance with maxmemory on, # the size of the output buffers needed to feed the slaves 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 slaves 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 slaves attached it is suggested that you set a lower # limit for maxmemory so that there is some free RAM on the system for slave # output buffers (but this is not needed if the policy is 'noeviction'). # # WARNING: not setting maxmemory will cause Redis to terminate with an # out-of-memory exception if the heap limit is reached. # # NOTE: since Redis uses the system paging file to allocate the heap memory, # the Working Set memory usage showed by the Windows Task Manager or by other # tools such as ProcessExplorer will not always be accurate. For example, right # after a background save of the RDB or the AOF files, the working set value # may drop significantly. In order to check the correct amount of memory used # by the redis-server to store the data, use the INFO client command. The INFO # command shows only the memory used to store the redis data, not the extra # memory used by the Windows process for its own requirements. Th3 extra amount # of memory not reported by the INFO command can be calculated subtracting the # Peak Working Set reported by the Windows Task Manager and the used_memory_peak # reported by the INFO command. # # 占用内存的大小,默认无限制——lgsp_Harold-Hua # maxmemory <bytes> maxmemory 500m # MAXMEMORY POLICY: how Redis will select what to remove when maxmemory # is reached. You can select among five behaviors: # # volatile-lru -> remove the key with an expire set using an LRU algorithm # allkeys-lru -> remove any key according to the LRU algorithm # volatile-random -> remove a random key with 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 expire at all, just return an error on write operations # # Note: with any of the above policies, Redis will return an error on write # operations, when there are no suitable keys for eviction. # # At the date of writing these commands are: set setnx setex append # incr decr rpush lpush rpushx lpushx linsert lset rpoplpush sadd # sinter sinterstore sunion sunionstore sdiff sdiffstore zadd zincrby # zunionstore zinterstore hset hsetnx hmset hincrby incrby decrby # getset mset msetnx exec sort # # The default is: # # maxmemory-policy noeviction # LRU 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. For default Redis will check five keys and pick the one that was # used less 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 a bit more CPU. 3 is very fast but not very accurate. # # maxmemory-samples 5 ############################## APPEND ONLY MODE ############################### # 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 http://redis.io/topics/persistence for more information. # 开启AOF备份——lgsp_Harold-Hua # appendonly no appendonly yes # The name of the append only file (default: "appendonly.aof") 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同步的频率——lgsp_Harold-Hua # appendfsync always appendfsync everysec # appendfsync no # 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 ################################ 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 called 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 ############################### # # ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ # WARNING EXPERIMENTAL: Redis Cluster is considered to be stable code, however # in order to mark it as "mature" we need to wait for a non trivial percentage # of users to deploy it in production. # ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ # # 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 multiple of the node timeout. # # cluster-node-timeout 15000 # A slave of a failing master will avoid to start a failover if its data # looks too old. # # There is no simple way for a slave to actually have a exact measure of # its "data age", so the following two checks are performed: # # 1) If there are multiple slaves able to failover, they exchange messages # in order to try to give an advantage to the slave with the best # replication offset (more data from the master processed). # Slaves 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 slave 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 slave will not try to failover # at all. # # The point "2" can be tuned by user. Specifically a slave will not perform # the failover if, since the last interaction with the master, the time # elapsed is greater than: # # (node-timeout * slave-validity-factor) + repl-ping-slave-period # # So for example if node-timeout is 30 seconds, and the slave-validity-factor # is 10, and assuming a default repl-ping-slave-period of 10 seconds, the # slave will not try to failover if it was not able to talk with the master # for longer than 310 seconds. # # A large slave-validity-factor may allow slaves with too old data to failover # a master, while a too small value may prevent the cluster from being able to # elect a slave at all. # # For maximum availability, it is possible to set the slave-validity-factor # to a value of 0, which means, that slaves 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-slave-validity-factor 10 # Cluster slaves are able to migrate to orphaned masters, that are masters # that are left without working slaves. 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 slaves. # # Slaves migrate to orphaned masters only if there are still at least a # given number of other working slaves for their old master. This number # is the "migration barrier". A migration barrier of 1 means that a slave # will migrate only if there is at least 1 other working slave for its master # and so forth. It usually reflects the number of slaves you want for every # master in your cluster. # # Default is 1 (slaves migrate only if their masters remain with at least # one slave). To disable migration just set it to a very large value. # A value of 0 can be set but is useful only for debugging and dangerous # in production. # # cluster-migration-barrier 1 # By default Redis Cluster nodes stop accepting queries if they detect there # is at least an 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 # In order to setup your cluster make sure to read the documentation # available at http://redis.io web site. ################################## 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 http://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) # A Alias for g$lshzxe, so that the "AKE" string means all the events. # # 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 "" ############################### 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 # 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 # slave -> slave 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 slave clients, since # subscribers and slaves 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 slave 256mb 64mb 60 client-output-buffer-limit pubsub 32mb 8mb 60 # Redis calls an internal function to perform many background tasks, like # closing connections of clients in timeot, purging expired keys that are # never requested, and so forth. # # Not all tasks are perforemd 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 # 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 ################################## INCLUDES ################################### # Include one or more other config files here. This is useful if you # have a standard template that goes to all Redis server but also need # to customize a few per-server settings. Include files can include # other files, so use this wisely. # # include /path/to/local.conf # include /path/to/other.conf
2、Redis字符串类型
2.1、字符串(String):最大存储512M数据
SET插入 >SET email scott@qq.com GET查询 >GET email DEL删除 >DEL email GETRANGE获取截取字符串内容 >GETRANGE email 0 3 STRLEN获得字符串长度 >STRLEN email SETEX设置带有过去时间(秒)的key-value >SETEX city 5 Beijing PSETEX设置带有过去时间(毫秒)的key-value >PSETEX city 5 Beijing MSET设置多个KEY-VALUE >MSET username scott sex male MGET获得多个VALUE >MGET username sex APPEND用于在字符串结尾追加内容 >SET temp ABCD >APPEND temp 1234 INCR数字自增加1 >INCR num INCRBY数字加上指定的整数值 >INCRBY num 25 INCRBYFLOAT数字加上指定的浮点数 >INCRBYFLOAT num 2.5 DECR数字自增减1 >DECR num 数字减去指定的整数值 >DECRBY num 10
2.2、哈希
HSET设置哈希表字段 >HSET 8000 ename Jim >HSET 8000 job SALESMAN HMSET设置哈希表多个字段 >HMSET 8000 ename TOM job SALESMAN deptno 10 HGET获得哈希表字段值 >HGET 8000 ename HMGET获取哈希表多个字字段值 >HMGET 8000 ename job deptno HGETALL获得哈希表所有 >HGETALL 8000 HKEYS获得哈希表所有字段名 >HKEYS 8000 HLEN获取哈希表中字段的数量 >HLEN 8000 HEXISTS判断哈希表是否存在某个字段 >HEXISTS 8000 job HVALS获得哈希表的所有字段值 >HVALS 8000 HDEL删除哈希表的字段 >HDEL 8000 job dept HINCRBY让哈希表某个字段值加上指定的整数值 >HINCRBY 8000 deptno 10 HINCRBYFLOAT 8000 sal 350.5
2.3、列表(值可以重复)
RPUSH向列表右侧添加数据 >RPUSH dname 技术部 后勤部 售后部 LPUSH向列表左侧添加数据 >LPUSH dname 秘书部 LSET修改列表的value值 >LSET dname 2 销售部 LRANGE输出列表所有value值 >LRANGE dname 0 -1 LLEN获得列表长度 >LLEN dname LINDEX获得列表某个元素 >LINDEX dname 2 LINSERT在某个位置插入元素 >LINSERT dname BEFORE[AFTER] 秘书处 董事会 LPOP删除最左侧的元素 >LPOP dname RPOP删除最右侧的元素 >RPOP dname LREM删除列表某些个元素 >LREM employee 2 scott
2.4、集合(值不可以重复)
SADD向集合添加元素 >SADD empno 8000 8001 8002 SMEMBERS无序获取集合所有元素 >SMEMBERS empno SCARD获得集合长度 >SCARD empno SISMEMBER判断是否含有某个元素 >SISMEMBER empno 8000 SREM删除元素 >SREM empno 8000 8001 SPOP随机删除并返回集合的某个元素 >SPOP empno SRANDMEMBER随机返回集合中的元素 >SRANDMEMBER empno 5
2.5、有序集合(有序集合带有排序功能的集合,Redis会按照元素分数值排序)
ZADD增加有序集合 >ZADD keyword 0 "AA" 0 "BB" 0 "CC" ZINCRBY加法运算 >ZINCRBY keyword 1 "AA" >ZINCRBY keyword 5 "BB" >ZINCRBY keyword 2 "CC" ZREVRANGE获得有序集合的内容(降序) >ZREVRANGE keyword 0 -1 >ZREVRANGE keyword 0 0 ZRANGE获得有序集合的内容(升序) >ZRANGE keyword 0 -1 >ZRANGE keyword 0 0 ZCARD获得有序集合长度 >ZCARD keyword ZCOUNT查询某个分数值区间内的元素数量 >ZCOUNT keyword 5 10 ZSCORE返回元素的分数值 >ZSCORE keyword "BB" ZRANGEBYSCORE获得分数值区间内的集合内容(升序) >ZRANGEBYSCORE keyword 5 10 >ZRANGEBYSCORE keyword 5 (10 >ZRANGEBYSCORE keyword 100000 +inf ZREVRANGEBYSCORE获得分数值区间内的集合内容(降序) >ZRANGEBYSCORE keyword 10 5
ZRANK获得元素的升序排名(从0开始) >ZRANK keyword "BB" ZREVRANK获得元素的降序排名(从0开始) >ZREVRANK keyword "BB" ZREM删除有序集合中的元素 >ZREM keyword "BB" "CC" ZREMRANGEBYRANK删除排名区间内的元素 >ZREMRANGEBYRANK keyword 0 2 ZREMRANGEBYSCORE删除分数值区间内的元素 >ZREMRANGEBYSCORE keyword -inf (5000
DEL删除记录 >DEL keyword EXISTS判断是否存在某个key >EXISTS employee EXPIRE设置记录过期时间(秒) >EXPIRE employee 5 EXPIRE设置记录过期时间(豪秒) >PEXPIRE employee 5000 EXPIREAT设置记录的过期时间(UNIX时间戳) >EXPIREAT employee 1644803200 MOVE把记录迁移到其他逻辑库 >MOVE keyword 1 RENAME修改key名称 >RENAME keyword tmp PERSIST移除过期时间 >PERSIST keyword TYPE判断VALUE数据类型 >TYPE keyword
3、Redis的事务
保持事务一致性:开启事务之前用WATCH命令监视要操作的记录
>WATCH kill_num kill_user
开启事务后所有操作都不会立即执行,只有执行EXEC命令的时候才会批处理执行
>MULTI >INCR kill_num >RPUSH kill_user 9502 >EXEC
取消事务:在事务没提交执行前,如提交则无法取消;被监视的数据没有发生变化,不然事务会被关闭。
>MULTI >... >DISCARD
4、安装redis-py
pip install redis
5、创建连接
import redis r = redis.Redis( host = "localhost", port = 6379, password = "root", db = 0 )
6、创建连接池
import redis pool = redis.ConnectionPool( host = "localhost", port = 6379, password = "root", db = 1, max_connections = 20 )
#!/usr/bin/env python3 # coding=utf-8 # Version:python3.6.1 # Project:pythonRedisProject # File:redis_db.py # Data:2020/10/21 19:58 # Author:LGSP_Harold import redis pool = redis.StrictRedis( host="localhost", port=6379, password="root", db=1, max_connections=20 )
7、创建与关闭连接
from redis_db import pool import redis conn = redis.Redis( connection_pool=pool )
...
del conn
#!/usr/bin/env python3 # coding=utf-8 # Version:python3.6.1 # Project:pythonRedisProject # File:example1.py # Data:2020/10/21 22:20 # Author:LGSP_Harold from redis_db import pool
connection_pool=pool
del connection_pool
8、操作指令
#!/usr/bin/env python3 # coding=utf-8 # Version:python3.6.1 # Project:pythonRedisProject # File:example1.py # Data:2020/10/21 22:20 # Author:LGSP_Harold from redis_db import pool
connection_pool = pool
connection_pool.set("country", "英国")
connection_pool.set("city", "伦敦")
city = connection_pool.get("city").decode("utf-8")
print(city)
del connection_pool
#!/usr/bin/env python3 # coding=utf-8 # Version:python3.6.1 # Project:pythonRedisProject # File:example_2.py # Data:2020/10/22 0:06 # Author:LGSP_Harold from redis_db import pool conn = pool try: conn.delete("country", "city") conn.mset({"country": "德国", "city": "柏林"}) rest = conn.mget("country", "city") print(rest) for one in rest: print(one.decode("utf-8")) except Exception as e: print(e) finally: del conn if __name__ == '__main__': pass
#!/usr/bin/env python3 # coding=utf-8 # Version:python3.6.1 # Project:pythonRedisProject # File:example_3.py # Data:2020/10/22 12:39 # Author:LGSP_Harold from redis_db import pool conn = pool try: conn.rpush("dname", "AA", "BB", "CC", "DD", "EE") conn.lpop("dname") rest = conn.lrange("dname", 0, -1) for one in rest: print(one.decode("utf-8")) except Exception as e: print(e) finally: del conn if __name__ == '__main__': pass
#!/usr/bin/env python3 # coding=utf-8 # Version:python3.6.1 # Project:pythonRedisProject # File:example_4.py # Data:2020/10/22 12:46 # Author:LGSP_Harold from redis_db import pool conn = pool try: conn.sadd("employee", 8001, 8002, 8003) conn.srem("employee", 8002) rest = conn.smembers("employee") for one in rest: print(one.decode("utf-8")) conn.zadd("keyword", {"AA": 0, "BB": 0, "CC": 0}) conn.zincrby("keyword", 10, "BB") rest = conn.zrevrange("keyword", 0, -1) for one in rest: print(one.decode("utf-8")) except Exception as e: print(e) finally: del conn if __name__ == '__main__': pass
#!/usr/bin/env python3 # coding=utf-8 # Version:python3.6.1 # Project:pythonRedisProject # File:example_5.py # Data:2020/10/22 22:52 # Author:LGSP_Harold from redis_db import pool conn = pool try: conn.hmset("9555", {"name": "scott", "age": 95, "sex": "male"}) conn.hset("9555", "city", "伦敦") conn.hdel("9555", "age") rest = conn.hexists("9555", "name") print(rest) rest = conn.hgetall("9555") print(rest) for one in rest: print(one,rest[one]) print(one.decode("utf-8"), rest[one].decode("utf-8")) except Exception as e: print(e) finally: del conn if __name__ == '__main__': pass
9、redis-py中哈希类型数据与事务管理
#!/usr/bin/env python3 # coding=utf-8 # Version:python3.6.1 # Project:pythonRedisProject # File:example_6.py # Data:2020/10/23 11:45 # Author:LGSP_Harold from redis_db import pool conn = pool try: pipline = conn.pipeline() pipline.watch("9555") pipline.multi() pipline.hset("9555", "name", "Jim") pipline.hset("9555", "age", 95) pipline.execute() except Exception as e: print(e) finally: if "pipline" in dir(): pipline.reset() del conn if __name__ == '__main__': pass
利用redis-py缓存学生考试信息
#!/usr/bin/env python3 # coding=utf-8 # Version:python3.6.1 # Project:pythonRedisProject # File:example_7.py # Data:2020/10/23 12:33 # Author:LGSP_Harold # 从TXT文档中解析学生的信息,把考试语数外成绩超过85分的同学信息,缓存到Redis的哈希表 """ 650,AA,2-1,77,88,99 651,BB,2-1,81,84,77 652,CC,2-2,99,88,44 653,DD,2-1,99,88,22 """ from redis_db import pool conn = pool try: file = open(file="example_7.txt", mode="r", encoding="utf-8") data = file.read().splitlines() print("data:", data) for one in data: temp = one.split(",") print("temp:", temp) sid = temp[0] name = temp[1] classmno = temp[2] score_1 = int(temp[3]) score_2 = int(temp[4]) score_3 = int(temp[5]) if score_1 >= 85 and score_2 >= 85 and score_3 >= 85: conn.hmset(sid, {"name": name, "classno": classmno, "score_1": score_1, "score_2": score_2, "score_3": score_3}) print("执行成功") except Exception as e: print(e) finally: if "file" in dir(): file.close() del conn if __name__ == '__main__': pass
缓存观众投票数据信息案例
#!/usr/bin/env python3 # coding=utf-8 # Version:python3.6.1 # Project:pythonRedisProject # File:example_8.py # Data:2020/10/23 17:47 # Author:LGSP_Harold # 模拟300位观众,为5位嘉宾随机投票,最后降序排列结果 from redis_db import pool import random conn = pool try: # conn.delete("ballot") names = ["Jim", "Harold", "Leslie", "Lucifer", "Adolph"] conn.zadd("ballot", {names[0]: 0, names[1]: 0, names[2]: 0, names[3]: 0, names[4]: 0}) for i in range(0, 300): num = random.randint(0, 4) name = names[num] conn.zincrby("ballot", 1, name) rest = conn.zrevrange("ballot", 0, -1, withscores=True) for one in rest: print(one[0].decode("utf-8"), int(one[1])) except Exception as e: print(e) finally: del conn if __name__ == '__main__': pass
模拟商品秒杀活动
EX:线程池
from concurrent.futures import ThreadPoolExecutor def say_hello(): print("Hello") executor = ThreadPoolExecutor(33) for i in range(0, 10): executor.submit(say_hello)
#!/usr/bin/env python3 # coding=utf-8 # Version:python3.6.1 # Project:pythonRedisProject # File:example_10.py # Data:2020/10/25 20:11 # Author:LGSP_Harold # 利用多线程模拟商品秒杀过程,不可以出现超买超卖的情况。假设A商品有50件参与秒杀活动,10分钟秒杀自动结束。 """ kill_total商品总数 kill_num成功抢购数 kill_flag有效标志位 kill_user成功抢购的用户ID """ from redis_db import pool import random from concurrent.futures import ThreadPoolExecutor s = set() while True: if len(s) == 1000: break num = random.randint(10000, 100000) s.add(num) conn = pool try: conn.delete("kill_total", "kill_num", "kill_flag", "kill_user") conn.set("kill_total", 50) conn.set("kill_num", 0) conn.set("kill_flag", 1) conn.expire("kill_flag", 600) except Exception as e: print(e) finally: del conn executor = ThreadPoolExecutor(200) def buy(): connection = pool pipeline = connection.pipeline() try: if connection.exists("kill_flag") == 1: pipeline.watch("kill_num", "kill_user") total = int(pipeline.get("kill_total").decode("utf-8")) num = int(pipeline.get("kill_num").decode("utf-8")) if num < total: pipeline.multi() pipeline.incr("kill_num") user_id = s.pop() pipeline.rpush("kill_user", user_id) pipeline.execute() except Exception as e: print(e) finally: if "pipeline" in dir(): pipeline.reset() del connection for i in range(0, 1000): executor.submit(buy) print("秒杀结束") if __name__ == '__main__': pass
P.S.1:Redis命令文档:http://doc.redisfans.com/
P.S.2:python操作Redis:https://www.cnblogs.com/john-xiong/p/12089103.html
略懂,略懂....