Redis

【1】conf文件如下：

# Redis configuration file example.## Note that in order to read the configuration file, Redis must be# started with the file path as first argument:## ./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:## 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 /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.## 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 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.# ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~bind 127.0.0.1# 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.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.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)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) 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 300 seconds, which is the new# Redis default starting with Redis 3.2.1.tcp-keepalive 300################################# 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.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#   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.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.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)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/nulllogfile ""# 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# 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'-1databases 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. 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.always-show-logo yes################################ 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 ""save 900 1save 300 10save 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.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 DBdbfilename 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.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.## Note that slaves never free the backlog for timeout, since they may be# promoted to masters later, and should be able to correctly "partially# resynchronize" with the slaves: hence they should always accumulate backlog.## 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.# A Redis master is able to list the address and port of the attached# slaves 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 slave instances.# Another place where this info is available is in the output of the# "ROLE" command of a master.## The listed IP and address normally reported by a slave is obtained# in the following way:##   IP: The address is auto detected by checking the peer address#   of the socket used by the slave to connect with the master.##   Port: The port is communicated by the slave during the replication#   handshake, and is normally the port that the slave is using to#   list for connections.## However when port forwarding or Network Address Translation (NAT) is# used, the slave may be actually reachable via different IP and port# pairs. The following two options can be used by a slave 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.## slave-announce-ip 5.5.5.5# slave-announce-port 1234################################## 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.## requirepass foobared# 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.################################### 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'.## 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 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').## maxmemory <bytes># MAXMEMORY POLICY: how Redis will select what to remove when maxmemory# is reached. You can select among five behaviors:## volatile-lru -> Evict using approximated LRU among the keys with an expire set.# allkeys-lru -> Evict any key using approximated LRU.# volatile-lfu -> Evict using approximated LFU among the keys with an expire set.# allkeys-lfu -> Evict any key using approximated LFU.# volatile-random -> Remove a random key among the ones 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 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, 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, 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. 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 more CPU. 3 is faster but not very accurate.## maxmemory-samples 5############################# 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 th 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 an 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 slave performs a full resynchronization with#    its master, the content of the whole database is removed in order to#    load the RDB file just transfered.## 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 nolazyfree-lazy-expire nolazyfree-lazy-server-del noslave-lazy-flush no############################## 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.appendonly no# 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".# appendfsync alwaysappendfsync 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 100auto-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, and continues loading the AOF# tail.## This is currently turned off by default in order to avoid the surprise# of a format change, but will at some point be used as the default.aof-use-rdb-preamble no################################ 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 an 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.########################## 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 known its public address is needed. The# following two options are used for this scope, and are:## * cluster-announce-ip# * cluster-announce-port# * cluster-announce-bus-port## Each instruct the node about its address, client port, 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 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 usually.## Example:## cluster-announce-ip 10.1.1.5# cluster-announce-port 6379# 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 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 512hash-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 128zset-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 0client-output-buffer-limit slave 256mb 64mb 60client-output-buffer-limit pubsub 32mb 8mb 60# 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# 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# 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 ######################### WARNING THIS FEATURE IS EXPERIMENTAL. However it was stress tested# even in production and manually tested by multiple engineers for some# time.## 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 an "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 yes# 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# active-defrag-cycle-min 25# Maximal effort for defrag in CPU percentage# active-defrag-cycle-max 75

---

【2】includes

和我们的Struts2配置文件类似，可以通过includes包含，redis.conf可以作为总闸，包含其他。

如果你有多个配置文件，可以引入进来作为总的最后的配置文件。

---

【3】NETWORK

• bind 127.0.0.1
  

  绑定的主机地址。

---

• port 6379
  

  默认端口 6379，一般都要更改

---

• tcp-backlog 511
  

  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 + 已经完成三次握手队列。
  
  在高并发环境下你需要一个高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

---

• timeout 0
  

  当一个客户端链接空闲N秒后，关闭链接。若N为0 ，表示禁用该功能。

---

• tcp-keepalive 300
  

  单位为秒，如果设置为0，则不会进行Keepalive检测，建议设置成60

---

【4】GENERAL

• daemonize yes

redis 默认非守护进程方式运行。可以将daemonize no修改为yes使其以守护进程方式运行。

---

• pidfile /var/run/redis_6379.pid

redis的进程管道pid文件。若未显示指定，则使用默认的。

---

• 日志级别和文件名

如下图所示，有四个日志级别：debug,verbose,notice和warning

---

• syslog-enabled no

  是否把日志输出到syslog中

• syslog-ident redis

  指定syslog里的日志标志

• syslog-facility local0

  指定syslog设备，值可以是USER或LOCAL0-LOCAL7,默认为local0

• database 16

  默认有16个数据库，默认使用第一个。

---

【5】SECURITY

Redis默认不使用密码，若想设置密码可以入下图所示设置。

---

【6】CLIENTS

设置redis同时可以与多少个客户端进行连接。默认情况下为10000个客户端。

当你无法设置进程文件句柄限制时，redis会设置为当前的文件句柄限制值减去32，因为redis会为自身内部处理逻辑留一些句柄出来。

如果达到了此限制，redis则会拒绝新的连接请求，并且向这些连接请求方发出“max number of clients reached”以作回应。

---

【7】MEMORY MANAGEMENT

• maxmemory <bytes>

设置redis可以使用的内存量。一旦到达内存使用上限，redis将会试图移除内部数据，移除规则可以通过maxmemory-policy来指定。

如果redis无法根据移除规则来移除内存中的数据，或者设置了“不允许移除”，那么redis则会针对那些需要申请内存的指令返回错误信息，比如SET、LPUSH等。

但是对于无内存申请的指令，仍然会正常响应，比如GET等。如果你的redis是主redis（说明你的redis有从redis），那么在设置内存使用上限时，需要在系统中留出一些内存空间给同步队列缓存，只有在你设置的是“不移除”的情况下，才不用考虑这个因素

---

• MAXMEMORY POLICY(缓存清理策略)

（1）volatile-lru：使用LRU算法移除key，只对设置了过期时间的键使用
（2）allkeys-lru：使用LRU算法移除key
（3）volatile-lfu：使用LFU算法移除key，只对设置了过期时间的键使用
（4）allkeys-lfu：使用LFU算法移除key
（5）volatile-random：在集合中移除随机的key，只对设置了过期时间的键
（6）allkeys-random：移除随机的key
（7）volatile-ttl：移除那些TTL值最小的key，即那些最近要过期的key
（8）noeviction：不进行移除。针对写操作，只是返回错误信息

LRU:最近最少使用；
LFU:使用次数最少;

---

Redis默认配置的为永不过期：

---

maxmemory-samples

设置样本数量。

LRU算法和最小TTL算法都并非是精确的算法，而是估算值。所以你可以设置样本的大小，redis默认会检查这么多个key并选择其中LRU的那个。

即，redis会根据你设置的样本数量进行算法间的检测比较，从而能够使你设置最优的缓存清理策略。

---