redis配置文件详解（转）

  1 # redis 配置文件示例  2   3 # 当你需要为某个配置项指定内存大小的时候，必须要带上单位，  4 # 通常的格式就是 1k 5gb 4m 等酱紫：  5 #  6 # 1k  => 1000 bytes  7 # 1kb => 1024 bytes  8 # 1m  => 1000000 bytes  9 # 1mb => 1024*1024 bytes 10 # 1g  => 1000000000 bytes 11 # 1gb => 1024*1024*1024 bytes 12 # 13 # 单位是不区分大小写的，你写 1K 5GB 4M 也行 14  15 ################################## INCLUDES ################################### 16  17 # 假如说你有一个可用于所有的 redis server 的标准配置模板， 18 # 但针对某些 server 又需要一些个性化的设置， 19 # 你可以使用 include 来包含一些其他的配置文件，这对你来说是非常有用的。 20 # 21 # 但是要注意哦，include 是不能被 config rewrite 命令改写的 22 # 由于 redis 总是以最后的加工线作为一个配置指令值，所以你最好是把 include 放在这个文件的最前面， 23 # 以避免在运行时覆盖配置的改变，相反，你就把它放在后面（外国人真啰嗦）。 24 # 25 # include /path/to/local.conf 26 # include /path/to/other.conf 27  28 ################################ 常用 ##################################### 29  30 # 默认情况下 redis 不是作为守护进程运行的，如果你想让它在后台运行，你就把它改成 yes。 31 # 当redis作为守护进程运行的时候，它会写一个 pid 到 /var/run/redis.pid 文件里面。 32 daemonize no 33  34 # 当redis作为守护进程运行的时候，它会把 pid 默认写到 /var/run/redis.pid 文件里面， 35 # 但是你可以在这里自己制定它的文件位置。 36 pidfile /var/run/redis.pid 37  38 # 监听端口号，默认为 6379，如果你设为 0 ，redis 将不在 socket 上监听任何客户端连接。 39 port 6379 40  41 # TCP 监听的最大容纳数量 42 # 43 # 在高并发的环境下，你需要把这个值调高以避免客户端连接缓慢的问题。 44 # Linux 内核会一声不响的把这个值缩小成 /proc/sys/net/core/somaxconn 对应的值， 45 # 所以你要修改这两个值才能达到你的预期。 46 tcp-backlog 511 47  48 # 默认情况下，redis 在 server 上所有有效的网络接口上监听客户端连接。 49 # 你如果只想让它在一个网络接口上监听，那你就绑定一个IP或者多个IP。 50 # 51 # 示例，多个IP用空格隔开: 52 # 53 # bind 192.168.1.100 10.0.0.1 54 # bind 127.0.0.1 55  56 # 指定 unix socket 的路径。 57 # 58 # unixsocket /tmp/redis.sock 59 # unixsocketperm 755 60  61 # 指定在一个 client 空闲多少秒之后关闭连接（0 就是不管它） 62 timeout 0 63  64 # tcp 心跳包。 65 # 66 # 如果设置为非零，则在与客户端缺乏通讯的时候使用 SO_KEEPALIVE 发送 tcp acks 给客户端。 67 # 这个之所有有用，主要由两个原因： 68 # 69 # 1) 防止死的 peers 70 # 2) Take the connection alive from the point of view of network 71 #    equipment in the middle. 72 # 73 # On Linux, the specified value (in seconds) is the period used to send ACKs. 74 # Note that to close the connection the double of the time is needed. 75 # On other kernels the period depends on the kernel configuration. 76 # 77 # A reasonable value for this option is 60 seconds. 78 # 推荐一个合理的值就是60秒 79 tcp-keepalive 0 80  81 # 定义日志级别。 82 # 可以是下面的这些值： 83 # debug (适用于开发或测试阶段) 84 # verbose (many rarely useful info, but not a mess like the debug level) 85 # notice (适用于生产环境) 86 # warning (仅仅一些重要的消息被记录) 87 loglevel notice 88  89 # 指定日志文件的位置 90 logfile "" 91  92 # 要想把日志记录到系统日志，就把它改成 yes， 93 # 也可以可选择性的更新其他的syslog 参数以达到你的要求 94 # syslog-enabled no 95  96 # 设置 syslog 的 identity。 97 # syslog-ident redis 98  99 # 设置 syslog 的 facility，必须是 USER 或者是 LOCAL0-LOCAL7 之间的值。100 # syslog-facility local0101 102 # 设置数据库的数目。103 # 默认数据库是 DB 0，你可以在每个连接上使用 select <dbid> 命令选择一个不同的数据库，104 # 但是 dbid 必须是一个介于 0 到 databasees - 1 之间的值105 databases 16106 107 ################################ 快照 ################################108 #109 # 存 DB 到磁盘：110 #111 #   格式：save <间隔时间（秒）> <写入次数>112 #113 #   根据给定的时间间隔和写入次数将数据保存到磁盘114 #115 #   下面的例子的意思是：116 #   900 秒后如果至少有 1 个 key 的值变化，则保存117 #   300 秒后如果至少有 10 个 key 的值变化，则保存118 #   60 秒后如果至少有 10000 个 key 的值变化，则保存119 #120 #   注意：你可以注释掉所有的 save 行来停用保存功能。121 #   也可以直接一个空字符串来实现停用：122 #   save ""123 124 save 900 1125 save 300 10126 save 60 10000127 128 # 默认情况下，如果 redis 最后一次的后台保存失败，redis 将停止接受写操作，129 # 这样以一种强硬的方式让用户知道数据不能正确的持久化到磁盘，130 # 否则就会没人注意到灾难的发生。131 #132 # 如果后台保存进程重新启动工作了，redis 也将自动的允许写操作。133 #134 # 然而你要是安装了靠谱的监控，你可能不希望 redis 这样做，那你就改成 no 好了。135 stop-writes-on-bgsave-error yes136 137 # 是否在 dump .rdb 数据库的时候使用 LZF 压缩字符串138 # 默认都设为 yes139 # 如果你希望保存子进程节省点 cpu ，你就设置它为 no ，140 # 不过这个数据集可能就会比较大141 rdbcompression yes142 143 # 是否校验rdb文件144 rdbchecksum yes145 146 # 设置 dump 的文件位置147 dbfilename dump.rdb148 149 # 工作目录150 # 例如上面的 dbfilename 只指定了文件名，151 # 但是它会写入到这个目录下。这个配置项一定是个目录，而不能是文件名。152 dir ./153 154 ################################# 主从复制 #################################155 156 # 主从复制。使用 slaveof 来让一个 redis 实例成为另一个reids 实例的副本。157 # 注意这个只需要在 slave 上配置。158 #159 # slaveof <masterip> <masterport>160 161 # 如果 master 需要密码认证，就在这里设置162 # masterauth <master-password>163 164 # 当一个 slave 与 master 失去联系，或者复制正在进行的时候，165 # slave 可能会有两种表现：166 #167 # 1) 如果为 yes ，slave 仍然会应答客户端请求，但返回的数据可能是过时，168 #    或者数据可能是空的在第一次同步的时候169 #170 # 2) 如果为 no ，在你执行除了 info he salveof 之外的其他命令时，171 #    slave 都将返回一个 "SYNC with master in progress" 的错误，172 #173 slave-serve-stale-data yes174 175 # 你可以配置一个 slave 实体是否接受写入操作。176 # 通过写入操作来存储一些短暂的数据对于一个 slave 实例来说可能是有用的，177 # 因为相对从 master 重新同步数而言，据数据写入到 slave 会更容易被删除。178 # 但是如果客户端因为一个错误的配置写入，也可能会导致一些问题。179 #180 # 从 redis 2.6 版起，默认 slaves 都是只读的。181 #182 # Note: read only slaves are not designed to be exposed to untrusted clients183 # on the internet. It's just a protection layer against misuse of the instance.184 # Still a read only slave exports by default all the administrative commands185 # such as CONFIG, DEBUG, and so forth. To a limited extent you can improve186 # security of read only slaves using 'rename-command' to shadow all the187 # administrative / dangerous commands.188 # 注意：只读的 slaves 没有被设计成在 internet 上暴露给不受信任的客户端。189 # 它仅仅是一个针对误用实例的一个保护层。190 slave-read-only yes191 192 # Slaves 在一个预定义的时间间隔内发送 ping 命令到 server 。193 # 你可以改变这个时间间隔。默认为 10 秒。194 #195 # repl-ping-slave-period 10196 197 # The following option sets the replication timeout for:198 # 设置主从复制过期时间199 #200 # 1) Bulk transfer I/O during SYNC, from the point of view of slave.201 # 2) Master timeout from the point of view of slaves (data, pings).202 # 3) Slave timeout from the point of view of masters (REPLCONF ACK pings).203 #204 # It is important to make sure that this value is greater than the value205 # specified for repl-ping-slave-period otherwise a timeout will be detected206 # every time there is low traffic between the master and the slave.207 # 这个值一定要比 repl-ping-slave-period 大208 #209 # repl-timeout 60210 211 # Disable TCP_NODELAY on the slave socket after SYNC?212 #213 # If you select "yes" Redis will use a smaller number of TCP packets and214 # less bandwidth to send data to slaves. But this can add a delay for215 # the data to appear on the slave side, up to 40 milliseconds with216 # Linux kernels using a default configuration.217 #218 # If you select "no" the delay for data to appear on the slave side will219 # be reduced but more bandwidth will be used for replication.220 #221 # By default we optimize for low latency, but in very high traffic conditions222 # or when the master and slaves are many hops away, turning this to "yes" may223 # be a good idea.224 repl-disable-tcp-nodelay no225 226 # 设置主从复制容量大小。这个 backlog 是一个用来在 slaves 被断开连接时227 # 存放 slave 数据的 buffer，所以当一个 slave 想要重新连接，通常不希望全部重新同步，228 # 只是部分同步就够了，仅仅传递 slave 在断开连接时丢失的这部分数据。229 #230 # The biggest the replication backlog, the longer the time the slave can be231 # disconnected and later be able to perform a partial resynchronization.232 # 这个值越大，salve 可以断开连接的时间就越长。233 #234 # The backlog is only allocated once there is at least a slave connected.235 #236 # repl-backlog-size 1mb237 238 # After a master has no longer connected slaves for some time, the backlog239 # will be freed. The following option configures the amount of seconds that240 # need to elapse, starting from the time the last slave disconnected, for241 # the backlog buffer to be freed.242 # 在某些时候，master 不再连接 slaves，backlog 将被释放。243 #244 # A value of 0 means to never release the backlog.245 # 如果设置为 0 ，意味着绝不释放 backlog 。246 #247 # repl-backlog-ttl 3600248 249 # 当 master 不能正常工作的时候，Redis Sentinel 会从 slaves 中选出一个新的 master，250 # 这个值越小，就越会被优先选中，但是如果是 0 ， 那是意味着这个 slave 不可能被选中。251 #252 # 默认优先级为 100。253 slave-priority 100254 255 # It is possible for a master to stop accepting writes if there are less than256 # N slaves connected, having a lag less or equal than M seconds.257 #258 # The N slaves need to be in "online" state.259 #260 # The lag in seconds, that must be <= the specified value, is calculated from261 # the last ping received from the slave, that is usually sent every second.262 #263 # This option does not GUARANTEES that N replicas will accept the write, but264 # will limit the window of exposure for lost writes in case not enough slaves265 # are available, to the specified number of seconds.266 #267 # For example to require at least 3 slaves with a lag <= 10 seconds use:268 #269 # min-slaves-to-write 3270 # min-slaves-max-lag 10271 #272 # Setting one or the other to 0 disables the feature.273 #274 # By default min-slaves-to-write is set to 0 (feature disabled) and275 # min-slaves-max-lag is set to 10.276 277 ################################## 安全 ###################################278 279 # Require clients to issue AUTH <PASSWORD> before processing any other280 # commands.  This might be useful in environments in which you do not trust281 # others with access to the host running redis-server.282 #283 # This should stay commented out for backward compatibility and because most284 # people do not need auth (e.g. they run their own servers).285 # 286 # Warning: since Redis is pretty fast an outside user can try up to287 # 150k passwords per second against a good box. This means that you should288 # use a very strong password otherwise it will be very easy to break.289 # 290 # 设置认证密码291 # requirepass foobared292 293 # Command renaming.294 #295 # It is possible to change the name of dangerous commands in a shared296 # environment. For instance the CONFIG command may be renamed into something297 # hard to guess so that it will still be available for internal-use tools298 # but not available for general clients.299 #300 # Example:301 #302 # rename-command CONFIG b840fc02d524045429941cc15f59e41cb7be6c52303 #304 # It is also possible to completely kill a command by renaming it into305 # an empty string:306 #307 # rename-command CONFIG ""308 #309 # Please note that changing the name of commands that are logged into the310 # AOF file or transmitted to slaves may cause problems.311 312 ################################### 限制 ####################################313 314 # Set the max number of connected clients at the same time. By default315 # this limit is set to 10000 clients, however if the Redis server is not316 # able to configure the process file limit to allow for the specified limit317 # the max number of allowed clients is set to the current file limit318 # minus 32 (as Redis reserves a few file descriptors for internal uses).319 #320 # 一旦达到最大限制，redis 将关闭所有的新连接321 # 并发送一个‘max number of clients reached’的错误。322 #323 # maxclients 10000324 325 # 如果你设置了这个值，当缓存的数据容量达到这个值， redis 将根据你选择的326 # eviction 策略来移除一些 keys。327 #328 # 如果 redis 不能根据策略移除 keys ，或者是策略被设置为 ‘noeviction’，329 # redis 将开始响应错误给命令，如 set，lpush 等等，330 # 并继续响应只读的命令，如 get331 #332 # This option is usually useful when using Redis as an LRU cache, or to set333 # a hard memory limit for an instance (using the 'noeviction' policy).334 #335 # WARNING: If you have slaves attached to an instance with maxmemory on,336 # the size of the output buffers needed to feed the slaves are subtracted337 # from the used memory count, so that network problems / resyncs will338 # not trigger a loop where keys are evicted, and in turn the output339 # buffer of slaves is full with DELs of keys evicted triggering the deletion340 # of more keys, and so forth until the database is completely emptied.341 #342 # In short... if you have slaves attached it is suggested that you set a lower343 # limit for maxmemory so that there is some free RAM on the system for slave344 # output buffers (but this is not needed if the policy is 'noeviction').345 #346 # 最大使用内存347 # maxmemory <bytes>348 349 # 最大内存策略，你有 5 个选择。350 # 351 # volatile-lru -> remove the key with an expire set using an LRU algorithm352 # volatile-lru -> 使用 LRU 算法移除包含过期设置的 key 。353 # allkeys-lru -> remove any key accordingly to the LRU algorithm354 # allkeys-lru -> 根据 LRU 算法移除所有的 key 。355 # volatile-random -> remove a random key with an expire set356 # allkeys-random -> remove a random key, any key357 # volatile-ttl -> remove the key with the nearest expire time (minor TTL)358 # noeviction -> don't expire at all, just return an error on write operations359 # noeviction -> 不让任何 key 过期，只是给写入操作返回一个错误360 # 361 # Note: with any of the above policies, Redis will return an error on write362 #       operations, when there are not suitable keys for eviction.363 #364 #       At the date of writing this commands are: set setnx setex append365 #       incr decr rpush lpush rpushx lpushx linsert lset rpoplpush sadd366 #       sinter sinterstore sunion sunionstore sdiff sdiffstore zadd zincrby367 #       zunionstore zinterstore hset hsetnx hmset hincrby incrby decrby368 #       getset mset msetnx exec sort369 #370 # The default is:371 #372 # maxmemory-policy noeviction373 374 # LRU and minimal TTL algorithms are not precise algorithms but approximated375 # algorithms (in order to save memory), so you can tune it for speed or376 # accuracy. For default Redis will check five keys and pick the one that was377 # used less recently, you can change the sample size using the following378 # configuration directive.379 #380 # The default of 5 produces good enough results. 10 Approximates very closely381 # true LRU but costs a bit more CPU. 3 is very fast but not very accurate.382 #383 # maxmemory-samples 5384 385 ############################## APPEND ONLY MODE ###############################386 387 # By default Redis asynchronously dumps the dataset on disk. This mode is388 # good enough in many applications, but an issue with the Redis process or389 # a power outage may result into a few minutes of writes lost (depending on390 # the configured save points).391 #392 # The Append Only File is an alternative persistence mode that provides393 # much better durability. For instance using the default data fsync policy394 # (see later in the config file) Redis can lose just one second of writes in a395 # dramatic event like a server power outage, or a single write if something396 # wrong with the Redis process itself happens, but the operating system is397 # still running correctly.398 #399 # AOF and RDB persistence can be enabled at the same time without problems.400 # If the AOF is enabled on startup Redis will load the AOF, that is the file401 # with the better durability guarantees.402 #403 # Please check http://redis.io/topics/persistence for more information.404 405 appendonly no406 407 # The name of the append only file (default: "appendonly.aof")408 409 appendfilename "appendonly.aof"410 411 # The fsync() call tells the Operating System to actually write data on disk412 # instead to wait for more data in the output buffer. Some OS will really flush 413 # data on disk, some other OS will just try to do it ASAP.414 #415 # Redis supports three different modes:416 #417 # no: don't fsync, just let the OS flush the data when it wants. Faster.418 # always: fsync after every write to the append only log . Slow, Safest.419 # everysec: fsync only one time every second. Compromise.420 #421 # The default is "everysec", as that's usually the right compromise between422 # speed and data safety. It's up to you to understand if you can relax this to423 # "no" that will let the operating system flush the output buffer when424 # it wants, for better performances (but if you can live with the idea of425 # some data loss consider the default persistence mode that's snapshotting),426 # or on the contrary, use "always" that's very slow but a bit safer than427 # everysec.428 #429 # More details please check the following article:430 # http://antirez.com/post/redis-persistence-demystified.html431 #432 # If unsure, use "everysec".433 434 # appendfsync always435 appendfsync everysec436 # appendfsync no437 438 # When the AOF fsync policy is set to always or everysec, and a background439 # saving process (a background save or AOF log background rewriting) is440 # performing a lot of I/O against the disk, in some Linux configurations441 # Redis may block too long on the fsync() call. Note that there is no fix for442 # this currently, as even performing fsync in a different thread will block443 # our synchronous write(2) call.444 #445 # In order to mitigate this problem it's possible to use the following option446 # that will prevent fsync() from being called in the main process while a447 # BGSAVE or BGREWRITEAOF is in progress.448 #449 # This means that while another child is saving, the durability of Redis is450 # the same as "appendfsync none". In practical terms, this means that it is451 # possible to lose up to 30 seconds of log in the worst scenario (with the452 # default Linux settings).453 # 454 # If you have latency problems turn this to "yes". Otherwise leave it as455 # "no" that is the safest pick from the point of view of durability.456 457 no-appendfsync-on-rewrite no458 459 # Automatic rewrite of the append only file.460 # Redis is able to automatically rewrite the log file implicitly calling461 # BGREWRITEAOF when the AOF log size grows by the specified percentage.462 # 463 # This is how it works: Redis remembers the size of the AOF file after the464 # latest rewrite (if no rewrite has happened since the restart, the size of465 # the AOF at startup is used).466 #467 # This base size is compared to the current size. If the current size is468 # bigger than the specified percentage, the rewrite is triggered. Also469 # you need to specify a minimal size for the AOF file to be rewritten, this470 # is useful to avoid rewriting the AOF file even if the percentage increase471 # is reached but it is still pretty small.472 #473 # Specify a percentage of zero in order to disable the automatic AOF474 # rewrite feature.475 476 auto-aof-rewrite-percentage 100477 auto-aof-rewrite-min-size 64mb478 479 ################################ LUA SCRIPTING  ###############################480 481 # Max execution time of a Lua script in milliseconds.482 #483 # If the maximum execution time is reached Redis will log that a script is484 # still in execution after the maximum allowed time and will start to485 # reply to queries with an error.486 #487 # When a long running script exceed the maximum execution time only the488 # SCRIPT KILL and SHUTDOWN NOSAVE commands are available. The first can be489 # used to stop a script that did not yet called write commands. The second490 # is the only way to shut down the server in the case a write commands was491 # already issue by the script but the user don't want to wait for the natural492 # termination of the script.493 #494 # Set it to 0 or a negative value for unlimited execution without warnings.495 lua-time-limit 5000496 497 ################################ REDIS 集群  ###############################498 #499 # 启用或停用集群500 # cluster-enabled yes501 502 # Every cluster node has a cluster configuration file. This file is not503 # intended to be edited by hand. It is created and updated by Redis nodes.504 # Every Redis Cluster node requires a different cluster configuration file.505 # Make sure that instances running in the same system does not have506 # overlapping cluster configuration file names.507 #508 # cluster-config-file nodes-6379.conf509 510 # Cluster node timeout is the amount of milliseconds a node must be unreachable 511 # for it to be considered in failure state.512 # Most other internal time limits are multiple of the node timeout.513 #514 # cluster-node-timeout 15000515 516 # A slave of a failing master will avoid to start a failover if its data517 # looks too old.518 #519 # There is no simple way for a slave to actually have a exact measure of520 # its "data age", so the following two checks are performed:521 #522 # 1) If there are multiple slaves able to failover, they exchange messages523 #    in order to try to give an advantage to the slave with the best524 #    replication offset (more data from the master processed).525 #    Slaves will try to get their rank by offset, and apply to the start526 #    of the failover a delay proportional to their rank.527 #528 # 2) Every single slave computes the time of the last interaction with529 #    its master. This can be the last ping or command received (if the master530 #    is still in the "connected" state), or the time that elapsed since the531 #    disconnection with the master (if the replication link is currently down).532 #    If the last interaction is too old, the slave will not try to failover533 #    at all.534 #535 # The point "2" can be tuned by user. Specifically a slave will not perform536 # the failover if, since the last interaction with the master, the time537 # elapsed is greater than:538 #539 #   (node-timeout * slave-validity-factor) + repl-ping-slave-period540 #541 # So for example if node-timeout is 30 seconds, and the slave-validity-factor542 # is 10, and assuming a default repl-ping-slave-period of 10 seconds, the543 # slave will not try to failover if it was not able to talk with the master544 # for longer than 310 seconds.545 #546 # A large slave-validity-factor may allow slaves with too old data to failover547 # a master, while a too small value may prevent the cluster from being able to548 # elect a slave at all.549 #550 # For maximum availability, it is possible to set the slave-validity-factor551 # to a value of 0, which means, that slaves will always try to failover the552 # master regardless of the last time they interacted with the master.553 # (However they'll always try to apply a delay proportional to their554 # offset rank).555 #556 # Zero is the only value able to guarantee that when all the partitions heal557 # the cluster will always be able to continue.558 #559 # cluster-slave-validity-factor 10560 561 # Cluster slaves are able to migrate to orphaned masters, that are masters562 # that are left without working slaves. This improves the cluster ability563 # to resist to failures as otherwise an orphaned master can't be failed over564 # in case of failure if it has no working slaves.565 #566 # Slaves migrate to orphaned masters only if there are still at least a567 # given number of other working slaves for their old master. This number568 # is the "migration barrier". A migration barrier of 1 means that a slave569 # will migrate only if there is at least 1 other working slave for its master570 # and so forth. It usually reflects the number of slaves you want for every571 # master in your cluster.572 #573 # Default is 1 (slaves migrate only if their masters remain with at least574 # one slave). To disable migration just set it to a very large value.575 # A value of 0 can be set but is useful only for debugging and dangerous576 # in production.577 #578 # cluster-migration-barrier 1579 580 # In order to setup your cluster make sure to read the documentation581 # available at http://redis.io web site.582 583 ################################## SLOW LOG ###################################584 585 # The Redis Slow Log is a system to log queries that exceeded a specified586 # execution time. The execution time does not include the I/O operations587 # like talking with the client, sending the reply and so forth,588 # but just the time needed to actually execute the command (this is the only589 # stage of command execution where the thread is blocked and can not serve590 # other requests in the meantime).591 # 592 # You can configure the slow log with two parameters: one tells Redis593 # what is the execution time, in microseconds, to exceed in order for the594 # command to get logged, and the other parameter is the length of the595 # slow log. When a new command is logged the oldest one is removed from the596 # queue of logged commands.597 598 # The following time is expressed in microseconds, so 1000000 is equivalent599 # to one second. Note that a negative number disables the slow log, while600 # a value of zero forces the logging of every command.601 slowlog-log-slower-than 10000602 603 # There is no limit to this length. Just be aware that it will consume memory.604 # You can reclaim memory used by the slow log with SLOWLOG RESET.605 slowlog-max-len 128606 607 ############################# Event notification ##############################608 609 # Redis can notify Pub/Sub clients about events happening in the key space.610 # This feature is documented at http://redis.io/topics/keyspace-events611 # 612 # For instance if keyspace events notification is enabled, and a client613 # performs a DEL operation on key "foo" stored in the Database 0, two614 # messages will be published via Pub/Sub:615 #616 # PUBLISH __keyspace@0__:foo del617 # PUBLISH __keyevent@0__:del foo618 #619 # It is possible to select the events that Redis will notify among a set620 # of classes. Every class is identified by a single character:621 #622 #  K     Keyspace events, published with __keyspace@<db>__ prefix.623 #  E     Keyevent events, published with __keyevent@<db>__ prefix.624 #  g     Generic commands (non-type specific) like DEL, EXPIRE, RENAME, ...625 #  $     String commands626 #  l     List commands627 #  s     Set commands628 #  h     Hash commands629 #  z     Sorted set commands630 #  x     Expired events (events generated every time a key expires)631 #  e     Evicted events (events generated when a key is evicted for maxmemory)632 #  A     Alias for g$lshzxe, so that the "AKE" string means all the events.633 #634 #  The "notify-keyspace-events" takes as argument a string that is composed635 #  by zero or multiple characters. The empty string means that notifications636 #  are disabled at all.637 #638 #  Example: to enable list and generic events, from the point of view of the639 #           event name, use:640 #641 #  notify-keyspace-events Elg642 #643 #  Example 2: to get the stream of the expired keys subscribing to channel644 #             name __keyevent@0__:expired use:645 #646 #  notify-keyspace-events Ex647 #648 #  By default all notifications are disabled because most users don't need649 #  this feature and the feature has some overhead. Note that if you don't650 #  specify at least one of K or E, no events will be delivered.651 notify-keyspace-events ""652 653 ############################### ADVANCED CONFIG ###############################654 655 # Hashes are encoded using a memory efficient data structure when they have a656 # small number of entries, and the biggest entry does not exceed a given657 # threshold. These thresholds can be configured using the following directives.658 hash-max-ziplist-entries 512659 hash-max-ziplist-value 64660 661 # Similarly to hashes, small lists are also encoded in a special way in order662 # to save a lot of space. The special representation is only used when663 # you are under the following limits:664 list-max-ziplist-entries 512665 list-max-ziplist-value 64666 667 # Sets have a special encoding in just one case: when a set is composed668 # of just strings that happens to be integers in radix 10 in the range669 # of 64 bit signed integers.670 # The following configuration setting sets the limit in the size of the671 # set in order to use this special memory saving encoding.672 set-max-intset-entries 512673 674 # Similarly to hashes and lists, sorted sets are also specially encoded in675 # order to save a lot of space. This encoding is only used when the length and676 # elements of a sorted set are below the following limits:677 zset-max-ziplist-entries 128678 zset-max-ziplist-value 64679 680 # HyperLogLog sparse representation bytes limit. The limit includes the681 # 16 bytes header. When an HyperLogLog using the sparse representation crosses682 # this limit, it is converted into the dense representation.683 #684 # A value greater than 16000 is totally useless, since at that point the685 # dense representation is more memory efficient.686 # 687 # The suggested value is ~ 3000 in order to have the benefits of688 # the space efficient encoding without slowing down too much PFADD,689 # which is O(N) with the sparse encoding. The value can be raised to690 # ~ 10000 when CPU is not a concern, but space is, and the data set is691 # composed of many HyperLogLogs with cardinality in the 0 - 15000 range.692 hll-sparse-max-bytes 3000693 694 # Active rehashing uses 1 millisecond every 100 milliseconds of CPU time in695 # order to help rehashing the main Redis hash table (the one mapping top-level696 # keys to values). The hash table implementation Redis uses (see dict.c)697 # performs a lazy rehashing: the more operation you run into a hash table698 # that is rehashing, the more rehashing "steps" are performed, so if the699 # server is idle the rehashing is never complete and some more memory is used700 # by the hash table.701 # 702 # The default is to use this millisecond 10 times every second in order to703 # active rehashing the main dictionaries, freeing memory when possible.704 #705 # If unsure:706 # use "activerehashing no" if you have hard latency requirements and it is707 # not a good thing in your environment that Redis can reply form time to time708 # to queries with 2 milliseconds delay.709 #710 # use "activerehashing yes" if you don't have such hard requirements but711 # want to free memory asap when possible.712 activerehashing yes713 714 # The client output buffer limits can be used to force disconnection of clients715 # that are not reading data from the server fast enough for some reason (a716 # common reason is that a Pub/Sub client can't consume messages as fast as the717 # publisher can produce them).718 #719 # The limit can be set differently for the three different classes of clients:720 #721 # normal -> normal clients722 # slave  -> slave clients and MONITOR clients723 # pubsub -> clients subscribed to at least one pubsub channel or pattern724 #725 # The syntax of every client-output-buffer-limit directive is the following:726 #727 # client-output-buffer-limit <class> <hard limit> <soft limit> <soft seconds>728 #729 # A client is immediately disconnected once the hard limit is reached, or if730 # the soft limit is reached and remains reached for the specified number of731 # seconds (continuously).732 # So for instance if the hard limit is 32 megabytes and the soft limit is733 # 16 megabytes / 10 seconds, the client will get disconnected immediately734 # if the size of the output buffers reach 32 megabytes, but will also get735 # disconnected if the client reaches 16 megabytes and continuously overcomes736 # the limit for 10 seconds.737 #738 # By default normal clients are not limited because they don't receive data739 # without asking (in a push way), but just after a request, so only740 # asynchronous clients may create a scenario where data is requested faster741 # than it can read.742 #743 # Instead there is a default limit for pubsub and slave clients, since744 # subscribers and slaves receive data in a push fashion.745 #746 # Both the hard or the soft limit can be disabled by setting them to zero.747 client-output-buffer-limit normal 0 0 0748 client-output-buffer-limit slave 256mb 64mb 60749 client-output-buffer-limit pubsub 32mb 8mb 60750 751 # Redis calls an internal function to perform many background tasks, like752 # closing connections of clients in timeout, purging expired keys that are753 # never requested, and so forth.754 #755 # Not all tasks are performed with the same frequency, but Redis checks for756 # tasks to perform accordingly to the specified "hz" value.757 #758 # By default "hz" is set to 10. Raising the value will use more CPU when759 # Redis is idle, but at the same time will make Redis more responsive when760 # there are many keys expiring at the same time, and timeouts may be761 # handled with more precision.762 #763 # The range is between 1 and 500, however a value over 100 is usually not764 # a good idea. Most users should use the default of 10 and raise this up to765 # 100 only in environments where very low latency is required.766 hz 10767 768 # When a child rewrites the AOF file, if the following option is enabled769 # the file will be fsync-ed every 32 MB of data generated. This is useful770 # in order to commit the file to the disk more incrementally and avoid771 # big latency spikes.772 aof-rewrite-incremental-fsync yes