16、Redis手动创建集群

 写在前面的话:读书破万卷,编码如有神

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1、手工创建集群
需要搭建的redis集群如下图所示:
1.1、 首先进行集群配置
(1)拷贝redis.conf文件6份,分别命名为:redis6381.conf、redis6382.conf、redis6383.conf、redis6384.conf、redis6385.conf、redis6386.conf
(2)只需要将每个数据库配置文件中的cluster-enable配置选项打开,然后再修改如下内容:pidfile、port、logfile、dbfilename、cluster-config-file
redis6381.conf 具体的配置如下:
   1 # Redis configuration file example.
   2 #
   3 # Note that in order to read the configuration file, Redis must be
   4 # started with the file path as first argument:
   5 #
   6 # ./redis-server /path/to/redis.conf
   7 
   8 # Note on units: when memory size is needed, it is possible to specify
   9 # it in the usual form of 1k 5GB 4M and so forth:
  10 #
  11 # 1k => 1000 bytes
  12 # 1kb => 1024 bytes
  13 # 1m => 1000000 bytes
  14 # 1mb => 1024*1024 bytes
  15 # 1g => 1000000000 bytes
  16 # 1gb => 1024*1024*1024 bytes
  17 #
  18 # units are case insensitive so 1GB 1Gb 1gB are all the same.
  19 
  20 ################################## INCLUDES ###################################
  21 
  22 # Include one or more other config files here.  This is useful if you
  23 # have a standard template that goes to all Redis servers but also need
  24 # to customize a few per-server settings.  Include files can include
  25 # other files, so use this wisely.
  26 #
  27 # Notice option "include" won't be rewritten by command "CONFIG REWRITE"
  28 # from admin or Redis Sentinel. Since Redis always uses the last processed
  29 # line as value of a configuration directive, you'd better put includes
  30 # at the beginning of this file to avoid overwriting config change at runtime.
  31 #
  32 # If instead you are interested in using includes to override configuration
  33 # options, it is better to use include as the last line.
  34 #
  35 # include /path/to/local.conf
  36 # include /path/to/other.conf
  37 
  38 ################################## MODULES #####################################
  39 
  40 # Load modules at startup. If the server is not able to load modules
  41 # it will abort. It is possible to use multiple loadmodule directives.
  42 #
  43 # loadmodule /path/to/my_module.so
  44 # loadmodule /path/to/other_module.so
  45 
  46 ################################## NETWORK #####################################
  47 
  48 # By default, if no "bind" configuration directive is specified, Redis listens
  49 # for connections from all the network interfaces available on the server.
  50 # It is possible to listen to just one or multiple selected interfaces using
  51 # the "bind" configuration directive, followed by one or more IP addresses.
  52 #
  53 # Examples:
  54 #
  55 # bind 192.168.1.100 10.0.0.1
  56 # bind 127.0.0.1 ::1
  57 #
  58 # ~~~ WARNING ~~~ If the computer running Redis is directly exposed to the
  59 # internet, binding to all the interfaces is dangerous and will expose the
  60 # instance to everybody on the internet. So by default we uncomment the
  61 # following bind directive, that will force Redis to listen only into
  62 # the IPv4 lookback interface address (this means Redis will be able to
  63 # accept connections only from clients running into the same computer it
  64 # is running).
  65 #
  66 # IF YOU ARE SURE YOU WANT YOUR INSTANCE TO LISTEN TO ALL THE INTERFACES
  67 # JUST COMMENT THE FOLLOWING LINE.
  68 # ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  69 bind 127.0.0.1
  70 
  71 # Protected mode is a layer of security protection, in order to avoid that
  72 # Redis instances left open on the internet are accessed and exploited.
  73 #
  74 # When protected mode is on and if:
  75 #
  76 # 1) The server is not binding explicitly to a set of addresses using the
  77 #    "bind" directive.
  78 # 2) No password is configured.
  79 #
  80 # The server only accepts connections from clients connecting from the
  81 # IPv4 and IPv6 loopback addresses 127.0.0.1 and ::1, and from Unix domain
  82 # sockets.
  83 #
  84 # By default protected mode is enabled. You should disable it only if
  85 # you are sure you want clients from other hosts to connect to Redis
  86 # even if no authentication is configured, nor a specific set of interfaces
  87 # are explicitly listed using the "bind" directive.
  88 protected-mode yes
  89 
  90 # Accept connections on the specified port, default is 6379 (IANA #815344).
  91 # If port 0 is specified Redis will not listen on a TCP socket.
  92 port 6381
  93 
  94 # TCP listen() backlog.
  95 #
  96 # In high requests-per-second environments you need an high backlog in order
  97 # to avoid slow clients connections issues. Note that the Linux kernel
  98 # will silently truncate it to the value of /proc/sys/net/core/somaxconn so
  99 # make sure to raise both the value of somaxconn and tcp_max_syn_backlog
 100 # in order to get the desired effect.
 101 tcp-backlog 511
 102 
 103 # Unix socket.
 104 #
 105 # Specify the path for the Unix socket that will be used to listen for
 106 # incoming connections. There is no default, so Redis will not listen
 107 # on a unix socket when not specified.
 108 #
 109 # unixsocket /tmp/redis.sock
 110 # unixsocketperm 700
 111 
 112 # Close the connection after a client is idle for N seconds (0 to disable)
 113 timeout 0
 114 
 115 # TCP keepalive.
 116 #
 117 # If non-zero, use SO_KEEPALIVE to send TCP ACKs to clients in absence
 118 # of communication. This is useful for two reasons:
 119 #
 120 # 1) Detect dead peers.
 121 # 2) Take the connection alive from the point of view of network
 122 #    equipment in the middle.
 123 #
 124 # On Linux, the specified value (in seconds) is the period used to send ACKs.
 125 # Note that to close the connection the double of the time is needed.
 126 # On other kernels the period depends on the kernel configuration.
 127 #
 128 # A reasonable value for this option is 300 seconds, which is the new
 129 # Redis default starting with Redis 3.2.1.
 130 tcp-keepalive 300
 131 
 132 ################################# GENERAL #####################################
 133 
 134 # By default Redis does not run as a daemon. Use 'yes' if you need it.
 135 # Note that Redis will write a pid file in /var/run/redis.pid when daemonized.
 136 daemonize yes
 137 
 138 # If you run Redis from upstart or systemd, Redis can interact with your
 139 # supervision tree. Options:
 140 #   supervised no      - no supervision interaction
 141 #   supervised upstart - signal upstart by putting Redis into SIGSTOP mode
 142 #   supervised systemd - signal systemd by writing READY=1 to $NOTIFY_SOCKET
 143 #   supervised auto    - detect upstart or systemd method based on
 144 #                        UPSTART_JOB or NOTIFY_SOCKET environment variables
 145 # Note: these supervision methods only signal "process is ready."
 146 #       They do not enable continuous liveness pings back to your supervisor.
 147 supervised no
 148 
 149 # If a pid file is specified, Redis writes it where specified at startup
 150 # and removes it at exit.
 151 #
 152 # When the server runs non daemonized, no pid file is created if none is
 153 # specified in the configuration. When the server is daemonized, the pid file
 154 # is used even if not specified, defaulting to "/var/run/redis.pid".
 155 #
 156 # Creating a pid file is best effort: if Redis is not able to create it
 157 # nothing bad happens, the server will start and run normally.
 158 pidfile /var/run/redis_6381.pid
 159 
 160 # Specify the server verbosity level.
 161 # This can be one of:
 162 # debug (a lot of information, useful for development/testing)
 163 # verbose (many rarely useful info, but not a mess like the debug level)
 164 # notice (moderately verbose, what you want in production probably)
 165 # warning (only very important / critical messages are logged)
 166 loglevel notice
 167 
 168 # Specify the log file name. Also the empty string can be used to force
 169 # Redis to log on the standard output. Note that if you use standard
 170 # output for logging but daemonize, logs will be sent to /dev/null
 171 logfile "redis_6381.log"
 172 
 173 # To enable logging to the system logger, just set 'syslog-enabled' to yes,
 174 # and optionally update the other syslog parameters to suit your needs.
 175 # syslog-enabled no
 176 
 177 # Specify the syslog identity.
 178 # syslog-ident redis
 179 
 180 # Specify the syslog facility. Must be USER or between LOCAL0-LOCAL7.
 181 # syslog-facility local0
 182 
 183 # Set the number of databases. The default database is DB 0, you can select
 184 # a different one on a per-connection basis using SELECT <dbid> where
 185 # dbid is a number between 0 and 'databases'-1
 186 databases 16
 187 
 188 # By default Redis shows an ASCII art logo only when started to log to the
 189 # standard output and if the standard output is a TTY. Basically this means
 190 # that normally a logo is displayed only in interactive sessions.
 191 #
 192 # However it is possible to force the pre-4.0 behavior and always show a
 193 # ASCII art logo in startup logs by setting the following option to yes.
 194 always-show-logo yes
 195 
 196 ################################ SNAPSHOTTING  ################################
 197 #
 198 # Save the DB on disk:
 199 #
 200 #   save <seconds> <changes>
 201 #
 202 #   Will save the DB if both the given number of seconds and the given
 203 #   number of write operations against the DB occurred.
 204 #
 205 #   In the example below the behaviour will be to save:
 206 #   after 900 sec (15 min) if at least 1 key changed
 207 #   after 300 sec (5 min) if at least 10 keys changed
 208 #   after 60 sec if at least 10000 keys changed
 209 #
 210 #   Note: you can disable saving completely by commenting out all "save" lines.
 211 #
 212 #   It is also possible to remove all the previously configured save
 213 #   points by adding a save directive with a single empty string argument
 214 #   like in the following example:
 215 #
 216 #   save ""
 217 
 218 save 900 1
 219 save 300 10
 220 save 60 10000
 221 
 222 # By default Redis will stop accepting writes if RDB snapshots are enabled
 223 # (at least one save point) and the latest background save failed.
 224 # This will make the user aware (in a hard way) that data is not persisting
 225 # on disk properly, otherwise chances are that no one will notice and some
 226 # disaster will happen.
 227 #
 228 # If the background saving process will start working again Redis will
 229 # automatically allow writes again.
 230 #
 231 # However if you have setup your proper monitoring of the Redis server
 232 # and persistence, you may want to disable this feature so that Redis will
 233 # continue to work as usual even if there are problems with disk,
 234 # permissions, and so forth.
 235 stop-writes-on-bgsave-error yes
 236 
 237 # Compress string objects using LZF when dump .rdb databases?
 238 # For default that's set to 'yes' as it's almost always a win.
 239 # If you want to save some CPU in the saving child set it to 'no' but
 240 # the dataset will likely be bigger if you have compressible values or keys.
 241 rdbcompression yes
 242 
 243 # Since version 5 of RDB a CRC64 checksum is placed at the end of the file.
 244 # This makes the format more resistant to corruption but there is a performance
 245 # hit to pay (around 10%) when saving and loading RDB files, so you can disable it
 246 # for maximum performances.
 247 #
 248 # RDB files created with checksum disabled have a checksum of zero that will
 249 # tell the loading code to skip the check.
 250 rdbchecksum yes
 251 
 252 # The filename where to dump the DB
 253 dbfilename dump_6381.rdb
 254 
 255 # The working directory.
 256 #
 257 # The DB will be written inside this directory, with the filename specified
 258 # above using the 'dbfilename' configuration directive.
 259 #
 260 # The Append Only File will also be created inside this directory.
 261 #
 262 # Note that you must specify a directory here, not a file name.
 263 dir ./
 264 
 265 ################################# REPLICATION #################################
 266 
 267 # Master-Slave replication. Use slaveof to make a Redis instance a copy of
 268 # another Redis server. A few things to understand ASAP about Redis replication.
 269 #
 270 # 1) Redis replication is asynchronous, but you can configure a master to
 271 #    stop accepting writes if it appears to be not connected with at least
 272 #    a given number of slaves.
 273 # 2) Redis slaves are able to perform a partial resynchronization with the
 274 #    master if the replication link is lost for a relatively small amount of
 275 #    time. You may want to configure the replication backlog size (see the next
 276 #    sections of this file) with a sensible value depending on your needs.
 277 # 3) Replication is automatic and does not need user intervention. After a
 278 #    network partition slaves automatically try to reconnect to masters
 279 #    and resynchronize with them.
 280 #
 281 # slaveof <masterip> <masterport>
 282 
 283 # If the master is password protected (using the "requirepass" configuration
 284 # directive below) it is possible to tell the slave to authenticate before
 285 # starting the replication synchronization process, otherwise the master will
 286 # refuse the slave request.
 287 #
 288 # masterauth <master-password>
 289 
 290 # When a slave loses its connection with the master, or when the replication
 291 # is still in progress, the slave can act in two different ways:
 292 #
 293 # 1) if slave-serve-stale-data is set to 'yes' (the default) the slave will
 294 #    still reply to client requests, possibly with out of date data, or the
 295 #    data set may just be empty if this is the first synchronization.
 296 #
 297 # 2) if slave-serve-stale-data is set to 'no' the slave will reply with
 298 #    an error "SYNC with master in progress" to all the kind of commands
 299 #    but to INFO and SLAVEOF.
 300 #
 301 slave-serve-stale-data yes
 302 
 303 # You can configure a slave instance to accept writes or not. Writing against
 304 # a slave instance may be useful to store some ephemeral data (because data
 305 # written on a slave will be easily deleted after resync with the master) but
 306 # may also cause problems if clients are writing to it because of a
 307 # misconfiguration.
 308 #
 309 # Since Redis 2.6 by default slaves are read-only.
 310 #
 311 # Note: read only slaves are not designed to be exposed to untrusted clients
 312 # on the internet. It's just a protection layer against misuse of the instance.
 313 # Still a read only slave exports by default all the administrative commands
 314 # such as CONFIG, DEBUG, and so forth. To a limited extent you can improve
 315 # security of read only slaves using 'rename-command' to shadow all the
 316 # administrative / dangerous commands.
 317 slave-read-only yes
 318 
 319 # Replication SYNC strategy: disk or socket.
 320 #
 321 # -------------------------------------------------------
 322 # WARNING: DISKLESS REPLICATION IS EXPERIMENTAL CURRENTLY
 323 # -------------------------------------------------------
 324 #
 325 # New slaves and reconnecting slaves that are not able to continue the replication
 326 # process just receiving differences, need to do what is called a "full
 327 # synchronization". An RDB file is transmitted from the master to the slaves.
 328 # The transmission can happen in two different ways:
 329 #
 330 # 1) Disk-backed: The Redis master creates a new process that writes the RDB
 331 #                 file on disk. Later the file is transferred by the parent
 332 #                 process to the slaves incrementally.
 333 # 2) Diskless: The Redis master creates a new process that directly writes the
 334 #              RDB file to slave sockets, without touching the disk at all.
 335 #
 336 # With disk-backed replication, while the RDB file is generated, more slaves
 337 # can be queued and served with the RDB file as soon as the current child producing
 338 # the RDB file finishes its work. With diskless replication instead once
 339 # the transfer starts, new slaves arriving will be queued and a new transfer
 340 # will start when the current one terminates.
 341 #
 342 # When diskless replication is used, the master waits a configurable amount of
 343 # time (in seconds) before starting the transfer in the hope that multiple slaves
 344 # will arrive and the transfer can be parallelized.
 345 #
 346 # With slow disks and fast (large bandwidth) networks, diskless replication
 347 # works better.
 348 repl-diskless-sync no
 349 
 350 # When diskless replication is enabled, it is possible to configure the delay
 351 # the server waits in order to spawn the child that transfers the RDB via socket
 352 # to the slaves.
 353 #
 354 # This is important since once the transfer starts, it is not possible to serve
 355 # new slaves arriving, that will be queued for the next RDB transfer, so the server
 356 # waits a delay in order to let more slaves arrive.
 357 #
 358 # The delay is specified in seconds, and by default is 5 seconds. To disable
 359 # it entirely just set it to 0 seconds and the transfer will start ASAP.
 360 repl-diskless-sync-delay 5
 361 
 362 # Slaves send PINGs to server in a predefined interval. It's possible to change
 363 # this interval with the repl_ping_slave_period option. The default value is 10
 364 # seconds.
 365 #
 366 # repl-ping-slave-period 10
 367 
 368 # The following option sets the replication timeout for:
 369 #
 370 # 1) Bulk transfer I/O during SYNC, from the point of view of slave.
 371 # 2) Master timeout from the point of view of slaves (data, pings).
 372 # 3) Slave timeout from the point of view of masters (REPLCONF ACK pings).
 373 #
 374 # It is important to make sure that this value is greater than the value
 375 # specified for repl-ping-slave-period otherwise a timeout will be detected
 376 # every time there is low traffic between the master and the slave.
 377 #
 378 # repl-timeout 60
 379 
 380 # Disable TCP_NODELAY on the slave socket after SYNC?
 381 #
 382 # If you select "yes" Redis will use a smaller number of TCP packets and
 383 # less bandwidth to send data to slaves. But this can add a delay for
 384 # the data to appear on the slave side, up to 40 milliseconds with
 385 # Linux kernels using a default configuration.
 386 #
 387 # If you select "no" the delay for data to appear on the slave side will
 388 # be reduced but more bandwidth will be used for replication.
 389 #
 390 # By default we optimize for low latency, but in very high traffic conditions
 391 # or when the master and slaves are many hops away, turning this to "yes" may
 392 # be a good idea.
 393 repl-disable-tcp-nodelay no
 394 
 395 # Set the replication backlog size. The backlog is a buffer that accumulates
 396 # slave data when slaves are disconnected for some time, so that when a slave
 397 # wants to reconnect again, often a full resync is not needed, but a partial
 398 # resync is enough, just passing the portion of data the slave missed while
 399 # disconnected.
 400 #
 401 # The bigger the replication backlog, the longer the time the slave can be
 402 # disconnected and later be able to perform a partial resynchronization.
 403 #
 404 # The backlog is only allocated once there is at least a slave connected.
 405 #
 406 # repl-backlog-size 1mb
 407 
 408 # After a master has no longer connected slaves for some time, the backlog
 409 # will be freed. The following option configures the amount of seconds that
 410 # need to elapse, starting from the time the last slave disconnected, for
 411 # the backlog buffer to be freed.
 412 #
 413 # Note that slaves never free the backlog for timeout, since they may be
 414 # promoted to masters later, and should be able to correctly "partially
 415 # resynchronize" with the slaves: hence they should always accumulate backlog.
 416 #
 417 # A value of 0 means to never release the backlog.
 418 #
 419 # repl-backlog-ttl 3600
 420 
 421 # The slave priority is an integer number published by Redis in the INFO output.
 422 # It is used by Redis Sentinel in order to select a slave to promote into a
 423 # master if the master is no longer working correctly.
 424 #
 425 # A slave with a low priority number is considered better for promotion, so
 426 # for instance if there are three slaves with priority 10, 100, 25 Sentinel will
 427 # pick the one with priority 10, that is the lowest.
 428 #
 429 # However a special priority of 0 marks the slave as not able to perform the
 430 # role of master, so a slave with priority of 0 will never be selected by
 431 # Redis Sentinel for promotion.
 432 #
 433 # By default the priority is 100.
 434 slave-priority 100
 435 
 436 # It is possible for a master to stop accepting writes if there are less than
 437 # N slaves connected, having a lag less or equal than M seconds.
 438 #
 439 # The N slaves need to be in "online" state.
 440 #
 441 # The lag in seconds, that must be <= the specified value, is calculated from
 442 # the last ping received from the slave, that is usually sent every second.
 443 #
 444 # This option does not GUARANTEE that N replicas will accept the write, but
 445 # will limit the window of exposure for lost writes in case not enough slaves
 446 # are available, to the specified number of seconds.
 447 #
 448 # For example to require at least 3 slaves with a lag <= 10 seconds use:
 449 #
 450 # min-slaves-to-write 3
 451 # min-slaves-max-lag 10
 452 #
 453 # Setting one or the other to 0 disables the feature.
 454 #
 455 # By default min-slaves-to-write is set to 0 (feature disabled) and
 456 # min-slaves-max-lag is set to 10.
 457 
 458 # A Redis master is able to list the address and port of the attached
 459 # slaves in different ways. For example the "INFO replication" section
 460 # offers this information, which is used, among other tools, by
 461 # Redis Sentinel in order to discover slave instances.
 462 # Another place where this info is available is in the output of the
 463 # "ROLE" command of a master.
 464 #
 465 # The listed IP and address normally reported by a slave is obtained
 466 # in the following way:
 467 #
 468 #   IP: The address is auto detected by checking the peer address
 469 #   of the socket used by the slave to connect with the master.
 470 #
 471 #   Port: The port is communicated by the slave during the replication
 472 #   handshake, and is normally the port that the slave is using to
 473 #   list for connections.
 474 #
 475 # However when port forwarding or Network Address Translation (NAT) is
 476 # used, the slave may be actually reachable via different IP and port
 477 # pairs. The following two options can be used by a slave in order to
 478 # report to its master a specific set of IP and port, so that both INFO
 479 # and ROLE will report those values.
 480 #
 481 # There is no need to use both the options if you need to override just
 482 # the port or the IP address.
 483 #
 484 # slave-announce-ip 5.5.5.5
 485 # slave-announce-port 1234
 486 
 487 ################################## SECURITY ###################################
 488 
 489 # Require clients to issue AUTH <PASSWORD> before processing any other
 490 # commands.  This might be useful in environments in which you do not trust
 491 # others with access to the host running redis-server.
 492 #
 493 # This should stay commented out for backward compatibility and because most
 494 # people do not need auth (e.g. they run their own servers).
 495 #
 496 # Warning: since Redis is pretty fast an outside user can try up to
 497 # 150k passwords per second against a good box. This means that you should
 498 # use a very strong password otherwise it will be very easy to break.
 499 #
 500 # requirepass foobared
 501 
 502 # Command renaming.
 503 #
 504 # It is possible to change the name of dangerous commands in a shared
 505 # environment. For instance the CONFIG command may be renamed into something
 506 # hard to guess so that it will still be available for internal-use tools
 507 # but not available for general clients.
 508 #
 509 # Example:
 510 #
 511 # rename-command CONFIG b840fc02d524045429941cc15f59e41cb7be6c52
 512 #
 513 # It is also possible to completely kill a command by renaming it into
 514 # an empty string:
 515 #
 516 # rename-command CONFIG ""
 517 #
 518 # Please note that changing the name of commands that are logged into the
 519 # AOF file or transmitted to slaves may cause problems.
 520 
 521 ################################### CLIENTS ####################################
 522 
 523 # Set the max number of connected clients at the same time. By default
 524 # this limit is set to 10000 clients, however if the Redis server is not
 525 # able to configure the process file limit to allow for the specified limit
 526 # the max number of allowed clients is set to the current file limit
 527 # minus 32 (as Redis reserves a few file descriptors for internal uses).
 528 #
 529 # Once the limit is reached Redis will close all the new connections sending
 530 # an error 'max number of clients reached'.
 531 #
 532 # maxclients 10000
 533 
 534 ############################## MEMORY MANAGEMENT ################################
 535 
 536 # Set a memory usage limit to the specified amount of bytes.
 537 # When the memory limit is reached Redis will try to remove keys
 538 # according to the eviction policy selected (see maxmemory-policy).
 539 #
 540 # If Redis can't remove keys according to the policy, or if the policy is
 541 # set to 'noeviction', Redis will start to reply with errors to commands
 542 # that would use more memory, like SET, LPUSH, and so on, and will continue
 543 # to reply to read-only commands like GET.
 544 #
 545 # This option is usually useful when using Redis as an LRU or LFU cache, or to
 546 # set a hard memory limit for an instance (using the 'noeviction' policy).
 547 #
 548 # WARNING: If you have slaves attached to an instance with maxmemory on,
 549 # the size of the output buffers needed to feed the slaves are subtracted
 550 # from the used memory count, so that network problems / resyncs will
 551 # not trigger a loop where keys are evicted, and in turn the output
 552 # buffer of slaves is full with DELs of keys evicted triggering the deletion
 553 # of more keys, and so forth until the database is completely emptied.
 554 #
 555 # In short... if you have slaves attached it is suggested that you set a lower
 556 # limit for maxmemory so that there is some free RAM on the system for slave
 557 # output buffers (but this is not needed if the policy is 'noeviction').
 558 #
 559 # maxmemory <bytes>
 560 
 561 # MAXMEMORY POLICY: how Redis will select what to remove when maxmemory
 562 # is reached. You can select among five behaviors:
 563 #
 564 # volatile-lru -> Evict using approximated LRU among the keys with an expire set.
 565 # allkeys-lru -> Evict any key using approximated LRU.
 566 # volatile-lfu -> Evict using approximated LFU among the keys with an expire set.
 567 # allkeys-lfu -> Evict any key using approximated LFU.
 568 # volatile-random -> Remove a random key among the ones with an expire set.
 569 # allkeys-random -> Remove a random key, any key.
 570 # volatile-ttl -> Remove the key with the nearest expire time (minor TTL)
 571 # noeviction -> Don't evict anything, just return an error on write operations.
 572 #
 573 # LRU means Least Recently Used
 574 # LFU means Least Frequently Used
 575 #
 576 # Both LRU, LFU and volatile-ttl are implemented using approximated
 577 # randomized algorithms.
 578 #
 579 # Note: with any of the above policies, Redis will return an error on write
 580 #       operations, when there are no suitable keys for eviction.
 581 #
 582 #       At the date of writing these commands are: set setnx setex append
 583 #       incr decr rpush lpush rpushx lpushx linsert lset rpoplpush sadd
 584 #       sinter sinterstore sunion sunionstore sdiff sdiffstore zadd zincrby
 585 #       zunionstore zinterstore hset hsetnx hmset hincrby incrby decrby
 586 #       getset mset msetnx exec sort
 587 #
 588 # The default is:
 589 #
 590 # maxmemory-policy noeviction
 591 
 592 # LRU, LFU and minimal TTL algorithms are not precise algorithms but approximated
 593 # algorithms (in order to save memory), so you can tune it for speed or
 594 # accuracy. For default Redis will check five keys and pick the one that was
 595 # used less recently, you can change the sample size using the following
 596 # configuration directive.
 597 #
 598 # The default of 5 produces good enough results. 10 Approximates very closely
 599 # true LRU but costs more CPU. 3 is faster but not very accurate.
 600 #
 601 # maxmemory-samples 5
 602 
 603 ############################# LAZY FREEING ####################################
 604 
 605 # Redis has two primitives to delete keys. One is called DEL and is a blocking
 606 # deletion of the object. It means that the server stops processing new commands
 607 # in order to reclaim all the memory associated with an object in a synchronous
 608 # way. If the key deleted is associated with a small object, the time needed
 609 # in order to execute the DEL command is very small and comparable to most other
 610 # O(1) or O(log_N) commands in Redis. However if the key is associated with an
 611 # aggregated value containing millions of elements, the server can block for
 612 # a long time (even seconds) in order to complete the operation.
 613 #
 614 # For the above reasons Redis also offers non blocking deletion primitives
 615 # such as UNLINK (non blocking DEL) and the ASYNC option of FLUSHALL and
 616 # FLUSHDB commands, in order to reclaim memory in background. Those commands
 617 # are executed in constant time. Another thread will incrementally free the
 618 # object in the background as fast as possible.
 619 #
 620 # DEL, UNLINK and ASYNC option of FLUSHALL and FLUSHDB are user-controlled.
 621 # It's up to the design of the application to understand when it is a good
 622 # idea to use one or the other. However the Redis server sometimes has to
 623 # delete keys or flush the whole database as a side effect of other operations.
 624 # Specifically Redis deletes objects independently of a user call in the
 625 # following scenarios:
 626 #
 627 # 1) On eviction, because of the maxmemory and maxmemory policy configurations,
 628 #    in order to make room for new data, without going over the specified
 629 #    memory limit.
 630 # 2) Because of expire: when a key with an associated time to live (see the
 631 #    EXPIRE command) must be deleted from memory.
 632 # 3) Because of a side effect of a command that stores data on a key that may
 633 #    already exist. For example the RENAME command may delete the old key
 634 #    content when it is replaced with another one. Similarly SUNIONSTORE
 635 #    or SORT with STORE option may delete existing keys. The SET command
 636 #    itself removes any old content of the specified key in order to replace
 637 #    it with the specified string.
 638 # 4) During replication, when a slave performs a full resynchronization with
 639 #    its master, the content of the whole database is removed in order to
 640 #    load the RDB file just transfered.
 641 #
 642 # In all the above cases the default is to delete objects in a blocking way,
 643 # like if DEL was called. However you can configure each case specifically
 644 # in order to instead release memory in a non-blocking way like if UNLINK
 645 # was called, using the following configuration directives:
 646 
 647 lazyfree-lazy-eviction no
 648 lazyfree-lazy-expire no
 649 lazyfree-lazy-server-del no
 650 slave-lazy-flush no
 651 
 652 ############################## APPEND ONLY MODE ###############################
 653 
 654 # By default Redis asynchronously dumps the dataset on disk. This mode is
 655 # good enough in many applications, but an issue with the Redis process or
 656 # a power outage may result into a few minutes of writes lost (depending on
 657 # the configured save points).
 658 #
 659 # The Append Only File is an alternative persistence mode that provides
 660 # much better durability. For instance using the default data fsync policy
 661 # (see later in the config file) Redis can lose just one second of writes in a
 662 # dramatic event like a server power outage, or a single write if something
 663 # wrong with the Redis process itself happens, but the operating system is
 664 # still running correctly.
 665 #
 666 # AOF and RDB persistence can be enabled at the same time without problems.
 667 # If the AOF is enabled on startup Redis will load the AOF, that is the file
 668 # with the better durability guarantees.
 669 #
 670 # Please check http://redis.io/topics/persistence for more information.
 671 
 672 appendonly no
 673 
 674 # The name of the append only file (default: "appendonly.aof")
 675 
 676 appendfilename "appendonly6381.aof"
 677 
 678 # The fsync() call tells the Operating System to actually write data on disk
 679 # instead of waiting for more data in the output buffer. Some OS will really flush
 680 # data on disk, some other OS will just try to do it ASAP.
 681 #
 682 # Redis supports three different modes:
 683 #
 684 # no: don't fsync, just let the OS flush the data when it wants. Faster.
 685 # always: fsync after every write to the append only log. Slow, Safest.
 686 # everysec: fsync only one time every second. Compromise.
 687 #
 688 # The default is "everysec", as that's usually the right compromise between
 689 # speed and data safety. It's up to you to understand if you can relax this to
 690 # "no" that will let the operating system flush the output buffer when
 691 # it wants, for better performances (but if you can live with the idea of
 692 # some data loss consider the default persistence mode that's snapshotting),
 693 # or on the contrary, use "always" that's very slow but a bit safer than
 694 # everysec.
 695 #
 696 # More details please check the following article:
 697 # http://antirez.com/post/redis-persistence-demystified.html
 698 #
 699 # If unsure, use "everysec".
 700 
 701 # appendfsync always
 702 appendfsync everysec
 703 # appendfsync no
 704 
 705 # When the AOF fsync policy is set to always or everysec, and a background
 706 # saving process (a background save or AOF log background rewriting) is
 707 # performing a lot of I/O against the disk, in some Linux configurations
 708 # Redis may block too long on the fsync() call. Note that there is no fix for
 709 # this currently, as even performing fsync in a different thread will block
 710 # our synchronous write(2) call.
 711 #
 712 # In order to mitigate this problem it's possible to use the following option
 713 # that will prevent fsync() from being called in the main process while a
 714 # BGSAVE or BGREWRITEAOF is in progress.
 715 #
 716 # This means that while another child is saving, the durability of Redis is
 717 # the same as "appendfsync none". In practical terms, this means that it is
 718 # possible to lose up to 30 seconds of log in the worst scenario (with the
 719 # default Linux settings).
 720 #
 721 # If you have latency problems turn this to "yes". Otherwise leave it as
 722 # "no" that is the safest pick from the point of view of durability.
 723 
 724 no-appendfsync-on-rewrite no
 725 
 726 # Automatic rewrite of the append only file.
 727 # Redis is able to automatically rewrite the log file implicitly calling
 728 # BGREWRITEAOF when the AOF log size grows by the specified percentage.
 729 #
 730 # This is how it works: Redis remembers the size of the AOF file after the
 731 # latest rewrite (if no rewrite has happened since the restart, the size of
 732 # the AOF at startup is used).
 733 #
 734 # This base size is compared to the current size. If the current size is
 735 # bigger than the specified percentage, the rewrite is triggered. Also
 736 # you need to specify a minimal size for the AOF file to be rewritten, this
 737 # is useful to avoid rewriting the AOF file even if the percentage increase
 738 # is reached but it is still pretty small.
 739 #
 740 # Specify a percentage of zero in order to disable the automatic AOF
 741 # rewrite feature.
 742 
 743 auto-aof-rewrite-percentage 100
 744 auto-aof-rewrite-min-size 64mb
 745 
 746 # An AOF file may be found to be truncated at the end during the Redis
 747 # startup process, when the AOF data gets loaded back into memory.
 748 # This may happen when the system where Redis is running
 749 # crashes, especially when an ext4 filesystem is mounted without the
 750 # data=ordered option (however this can't happen when Redis itself
 751 # crashes or aborts but the operating system still works correctly).
 752 #
 753 # Redis can either exit with an error when this happens, or load as much
 754 # data as possible (the default now) and start if the AOF file is found
 755 # to be truncated at the end. The following option controls this behavior.
 756 #
 757 # If aof-load-truncated is set to yes, a truncated AOF file is loaded and
 758 # the Redis server starts emitting a log to inform the user of the event.
 759 # Otherwise if the option is set to no, the server aborts with an error
 760 # and refuses to start. When the option is set to no, the user requires
 761 # to fix the AOF file using the "redis-check-aof" utility before to restart
 762 # the server.
 763 #
 764 # Note that if the AOF file will be found to be corrupted in the middle
 765 # the server will still exit with an error. This option only applies when
 766 # Redis will try to read more data from the AOF file but not enough bytes
 767 # will be found.
 768 aof-load-truncated yes
 769 
 770 # When rewriting the AOF file, Redis is able to use an RDB preamble in the
 771 # AOF file for faster rewrites and recoveries. When this option is turned
 772 # on the rewritten AOF file is composed of two different stanzas:
 773 #
 774 #   [RDB file][AOF tail]
 775 #
 776 # When loading Redis recognizes that the AOF file starts with the "REDIS"
 777 # string and loads the prefixed RDB file, and continues loading the AOF
 778 # tail.
 779 #
 780 # This is currently turned off by default in order to avoid the surprise
 781 # of a format change, but will at some point be used as the default.
 782 aof-use-rdb-preamble no
 783 
 784 ################################ LUA SCRIPTING  ###############################
 785 
 786 # Max execution time of a Lua script in milliseconds.
 787 #
 788 # If the maximum execution time is reached Redis will log that a script is
 789 # still in execution after the maximum allowed time and will start to
 790 # reply to queries with an error.
 791 #
 792 # When a long running script exceeds the maximum execution time only the
 793 # SCRIPT KILL and SHUTDOWN NOSAVE commands are available. The first can be
 794 # used to stop a script that did not yet called write commands. The second
 795 # is the only way to shut down the server in the case a write command was
 796 # already issued by the script but the user doesn't want to wait for the natural
 797 # termination of the script.
 798 #
 799 # Set it to 0 or a negative value for unlimited execution without warnings.
 800 lua-time-limit 5000
 801 
 802 ################################ REDIS CLUSTER  ###############################
 803 #
 804 # ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 805 # WARNING EXPERIMENTAL: Redis Cluster is considered to be stable code, however
 806 # in order to mark it as "mature" we need to wait for a non trivial percentage
 807 # of users to deploy it in production.
 808 # ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 809 #
 810 # Normal Redis instances can't be part of a Redis Cluster; only nodes that are
 811 # started as cluster nodes can. In order to start a Redis instance as a
 812 # cluster node enable the cluster support uncommenting the following:
 813 #
 814 cluster-enabled yes
 815 
 816 # Every cluster node has a cluster configuration file. This file is not
 817 # intended to be edited by hand. It is created and updated by Redis nodes.
 818 # Every Redis Cluster node requires a different cluster configuration file.
 819 # Make sure that instances running in the same system do not have
 820 # overlapping cluster configuration file names.
 821 #
 822 cluster-config-file nodes-6381.conf
 823 
 824 # Cluster node timeout is the amount of milliseconds a node must be unreachable
 825 # for it to be considered in failure state.
 826 # Most other internal time limits are multiple of the node timeout.
 827 #
 828 # cluster-node-timeout 15000
 829 
 830 # A slave of a failing master will avoid to start a failover if its data
 831 # looks too old.
 832 #
 833 # There is no simple way for a slave to actually have an exact measure of
 834 # its "data age", so the following two checks are performed:
 835 #
 836 # 1) If there are multiple slaves able to failover, they exchange messages
 837 #    in order to try to give an advantage to the slave with the best
 838 #    replication offset (more data from the master processed).
 839 #    Slaves will try to get their rank by offset, and apply to the start
 840 #    of the failover a delay proportional to their rank.
 841 #
 842 # 2) Every single slave computes the time of the last interaction with
 843 #    its master. This can be the last ping or command received (if the master
 844 #    is still in the "connected" state), or the time that elapsed since the
 845 #    disconnection with the master (if the replication link is currently down).
 846 #    If the last interaction is too old, the slave will not try to failover
 847 #    at all.
 848 #
 849 # The point "2" can be tuned by user. Specifically a slave will not perform
 850 # the failover if, since the last interaction with the master, the time
 851 # elapsed is greater than:
 852 #
 853 #   (node-timeout * slave-validity-factor) + repl-ping-slave-period
 854 #
 855 # So for example if node-timeout is 30 seconds, and the slave-validity-factor
 856 # is 10, and assuming a default repl-ping-slave-period of 10 seconds, the
 857 # slave will not try to failover if it was not able to talk with the master
 858 # for longer than 310 seconds.
 859 #
 860 # A large slave-validity-factor may allow slaves with too old data to failover
 861 # a master, while a too small value may prevent the cluster from being able to
 862 # elect a slave at all.
 863 #
 864 # For maximum availability, it is possible to set the slave-validity-factor
 865 # to a value of 0, which means, that slaves will always try to failover the
 866 # master regardless of the last time they interacted with the master.
 867 # (However they'll always try to apply a delay proportional to their
 868 # offset rank).
 869 #
 870 # Zero is the only value able to guarantee that when all the partitions heal
 871 # the cluster will always be able to continue.
 872 #
 873 # cluster-slave-validity-factor 10
 874 
 875 # Cluster slaves are able to migrate to orphaned masters, that are masters
 876 # that are left without working slaves. This improves the cluster ability
 877 # to resist to failures as otherwise an orphaned master can't be failed over
 878 # in case of failure if it has no working slaves.
 879 #
 880 # Slaves migrate to orphaned masters only if there are still at least a
 881 # given number of other working slaves for their old master. This number
 882 # is the "migration barrier". A migration barrier of 1 means that a slave
 883 # will migrate only if there is at least 1 other working slave for its master
 884 # and so forth. It usually reflects the number of slaves you want for every
 885 # master in your cluster.
 886 #
 887 # Default is 1 (slaves migrate only if their masters remain with at least
 888 # one slave). To disable migration just set it to a very large value.
 889 # A value of 0 can be set but is useful only for debugging and dangerous
 890 # in production.
 891 #
 892 # cluster-migration-barrier 1
 893 
 894 # By default Redis Cluster nodes stop accepting queries if they detect there
 895 # is at least an hash slot uncovered (no available node is serving it).
 896 # This way if the cluster is partially down (for example a range of hash slots
 897 # are no longer covered) all the cluster becomes, eventually, unavailable.
 898 # It automatically returns available as soon as all the slots are covered again.
 899 #
 900 # However sometimes you want the subset of the cluster which is working,
 901 # to continue to accept queries for the part of the key space that is still
 902 # covered. In order to do so, just set the cluster-require-full-coverage
 903 # option to no.
 904 #
 905 # cluster-require-full-coverage yes
 906 
 907 # In order to setup your cluster make sure to read the documentation
 908 # available at http://redis.io web site.
 909 
 910 ########################## CLUSTER DOCKER/NAT support  ########################
 911 
 912 # In certain deployments, Redis Cluster nodes address discovery fails, because
 913 # addresses are NAT-ted or because ports are forwarded (the typical case is
 914 # Docker and other containers).
 915 #
 916 # In order to make Redis Cluster working in such environments, a static
 917 # configuration where each node knows its public address is needed. The
 918 # following two options are used for this scope, and are:
 919 #
 920 # * cluster-announce-ip
 921 # * cluster-announce-port
 922 # * cluster-announce-bus-port
 923 #
 924 # Each instruct the node about its address, client port, and cluster message
 925 # bus port. The information is then published in the header of the bus packets
 926 # so that other nodes will be able to correctly map the address of the node
 927 # publishing the information.
 928 #
 929 # If the above options are not used, the normal Redis Cluster auto-detection
 930 # will be used instead.
 931 #
 932 # Note that when remapped, the bus port may not be at the fixed offset of
 933 # clients port + 10000, so you can specify any port and bus-port depending
 934 # on how they get remapped. If the bus-port is not set, a fixed offset of
 935 # 10000 will be used as usually.
 936 #
 937 # Example:
 938 #
 939 # cluster-announce-ip 10.1.1.5
 940 # cluster-announce-port 6379
 941 # cluster-announce-bus-port 6380
 942 
 943 ################################## SLOW LOG ###################################
 944 
 945 # The Redis Slow Log is a system to log queries that exceeded a specified
 946 # execution time. The execution time does not include the I/O operations
 947 # like talking with the client, sending the reply and so forth,
 948 # but just the time needed to actually execute the command (this is the only
 949 # stage of command execution where the thread is blocked and can not serve
 950 # other requests in the meantime).
 951 #
 952 # You can configure the slow log with two parameters: one tells Redis
 953 # what is the execution time, in microseconds, to exceed in order for the
 954 # command to get logged, and the other parameter is the length of the
 955 # slow log. When a new command is logged the oldest one is removed from the
 956 # queue of logged commands.
 957 
 958 # The following time is expressed in microseconds, so 1000000 is equivalent
 959 # to one second. Note that a negative number disables the slow log, while
 960 # a value of zero forces the logging of every command.
 961 slowlog-log-slower-than 10000
 962 
 963 # There is no limit to this length. Just be aware that it will consume memory.
 964 # You can reclaim memory used by the slow log with SLOWLOG RESET.
 965 slowlog-max-len 128
 966 
 967 ################################ LATENCY MONITOR ##############################
 968 
 969 # The Redis latency monitoring subsystem samples different operations
 970 # at runtime in order to collect data related to possible sources of
 971 # latency of a Redis instance.
 972 #
 973 # Via the LATENCY command this information is available to the user that can
 974 # print graphs and obtain reports.
 975 #
 976 # The system only logs operations that were performed in a time equal or
 977 # greater than the amount of milliseconds specified via the
 978 # latency-monitor-threshold configuration directive. When its value is set
 979 # to zero, the latency monitor is turned off.
 980 #
 981 # By default latency monitoring is disabled since it is mostly not needed
 982 # if you don't have latency issues, and collecting data has a performance
 983 # impact, that while very small, can be measured under big load. Latency
 984 # monitoring can easily be enabled at runtime using the command
 985 # "CONFIG SET latency-monitor-threshold <milliseconds>" if needed.
 986 latency-monitor-threshold 0
 987 
 988 ############################# EVENT NOTIFICATION ##############################
 989 
 990 # Redis can notify Pub/Sub clients about events happening in the key space.
 991 # This feature is documented at http://redis.io/topics/notifications
 992 #
 993 # For instance if keyspace events notification is enabled, and a client
 994 # performs a DEL operation on key "foo" stored in the Database 0, two
 995 # messages will be published via Pub/Sub:
 996 #
 997 # PUBLISH __keyspace@0__:foo del
 998 # PUBLISH __keyevent@0__:del foo
 999 #
1000 # It is possible to select the events that Redis will notify among a set
1001 # of classes. Every class is identified by a single character:
1002 #
1003 #  K     Keyspace events, published with __keyspace@<db>__ prefix.
1004 #  E     Keyevent events, published with __keyevent@<db>__ prefix.
1005 #  g     Generic commands (non-type specific) like DEL, EXPIRE, RENAME, ...
1006 #  $     String commands
1007 #  l     List commands
1008 #  s     Set commands
1009 #  h     Hash commands
1010 #  z     Sorted set commands
1011 #  x     Expired events (events generated every time a key expires)
1012 #  e     Evicted events (events generated when a key is evicted for maxmemory)
1013 #  A     Alias for g$lshzxe, so that the "AKE" string means all the events.
1014 #
1015 #  The "notify-keyspace-events" takes as argument a string that is composed
1016 #  of zero or multiple characters. The empty string means that notifications
1017 #  are disabled.
1018 #
1019 #  Example: to enable list and generic events, from the point of view of the
1020 #           event name, use:
1021 #
1022 #  notify-keyspace-events Elg
1023 #
1024 #  Example 2: to get the stream of the expired keys subscribing to channel
1025 #             name __keyevent@0__:expired use:
1026 #
1027 #  notify-keyspace-events Ex
1028 #
1029 #  By default all notifications are disabled because most users don't need
1030 #  this feature and the feature has some overhead. Note that if you don't
1031 #  specify at least one of K or E, no events will be delivered.
1032 notify-keyspace-events ""
1033 
1034 ############################### ADVANCED CONFIG ###############################
1035 
1036 # Hashes are encoded using a memory efficient data structure when they have a
1037 # small number of entries, and the biggest entry does not exceed a given
1038 # threshold. These thresholds can be configured using the following directives.
1039 hash-max-ziplist-entries 512
1040 hash-max-ziplist-value 64
1041 
1042 # Lists are also encoded in a special way to save a lot of space.
1043 # The number of entries allowed per internal list node can be specified
1044 # as a fixed maximum size or a maximum number of elements.
1045 # For a fixed maximum size, use -5 through -1, meaning:
1046 # -5: max size: 64 Kb  <-- not recommended for normal workloads
1047 # -4: max size: 32 Kb  <-- not recommended
1048 # -3: max size: 16 Kb  <-- probably not recommended
1049 # -2: max size: 8 Kb   <-- good
1050 # -1: max size: 4 Kb   <-- good
1051 # Positive numbers mean store up to _exactly_ that number of elements
1052 # per list node.
1053 # The highest performing option is usually -2 (8 Kb size) or -1 (4 Kb size),
1054 # but if your use case is unique, adjust the settings as necessary.
1055 list-max-ziplist-size -2
1056 
1057 # Lists may also be compressed.
1058 # Compress depth is the number of quicklist ziplist nodes from *each* side of
1059 # the list to *exclude* from compression.  The head and tail of the list
1060 # are always uncompressed for fast push/pop operations.  Settings are:
1061 # 0: disable all list compression
1062 # 1: depth 1 means "don't start compressing until after 1 node into the list,
1063 #    going from either the head or tail"
1064 #    So: [head]->node->node->...->node->[tail]
1065 #    [head], [tail] will always be uncompressed; inner nodes will compress.
1066 # 2: [head]->[next]->node->node->...->node->[prev]->[tail]
1067 #    2 here means: don't compress head or head->next or tail->prev or tail,
1068 #    but compress all nodes between them.
1069 # 3: [head]->[next]->[next]->node->node->...->node->[prev]->[prev]->[tail]
1070 # etc.
1071 list-compress-depth 0
1072 
1073 # Sets have a special encoding in just one case: when a set is composed
1074 # of just strings that happen to be integers in radix 10 in the range
1075 # of 64 bit signed integers.
1076 # The following configuration setting sets the limit in the size of the
1077 # set in order to use this special memory saving encoding.
1078 set-max-intset-entries 512
1079 
1080 # Similarly to hashes and lists, sorted sets are also specially encoded in
1081 # order to save a lot of space. This encoding is only used when the length and
1082 # elements of a sorted set are below the following limits:
1083 zset-max-ziplist-entries 128
1084 zset-max-ziplist-value 64
1085 
1086 # HyperLogLog sparse representation bytes limit. The limit includes the
1087 # 16 bytes header. When an HyperLogLog using the sparse representation crosses
1088 # this limit, it is converted into the dense representation.
1089 #
1090 # A value greater than 16000 is totally useless, since at that point the
1091 # dense representation is more memory efficient.
1092 #
1093 # The suggested value is ~ 3000 in order to have the benefits of
1094 # the space efficient encoding without slowing down too much PFADD,
1095 # which is O(N) with the sparse encoding. The value can be raised to
1096 # ~ 10000 when CPU is not a concern, but space is, and the data set is
1097 # composed of many HyperLogLogs with cardinality in the 0 - 15000 range.
1098 hll-sparse-max-bytes 3000
1099 
1100 # Active rehashing uses 1 millisecond every 100 milliseconds of CPU time in
1101 # order to help rehashing the main Redis hash table (the one mapping top-level
1102 # keys to values). The hash table implementation Redis uses (see dict.c)
1103 # performs a lazy rehashing: the more operation you run into a hash table
1104 # that is rehashing, the more rehashing "steps" are performed, so if the
1105 # server is idle the rehashing is never complete and some more memory is used
1106 # by the hash table.
1107 #
1108 # The default is to use this millisecond 10 times every second in order to
1109 # actively rehash the main dictionaries, freeing memory when possible.
1110 #
1111 # If unsure:
1112 # use "activerehashing no" if you have hard latency requirements and it is
1113 # not a good thing in your environment that Redis can reply from time to time
1114 # to queries with 2 milliseconds delay.
1115 #
1116 # use "activerehashing yes" if you don't have such hard requirements but
1117 # want to free memory asap when possible.
1118 activerehashing yes
1119 
1120 # The client output buffer limits can be used to force disconnection of clients
1121 # that are not reading data from the server fast enough for some reason (a
1122 # common reason is that a Pub/Sub client can't consume messages as fast as the
1123 # publisher can produce them).
1124 #
1125 # The limit can be set differently for the three different classes of clients:
1126 #
1127 # normal -> normal clients including MONITOR clients
1128 # slave  -> slave clients
1129 # pubsub -> clients subscribed to at least one pubsub channel or pattern
1130 #
1131 # The syntax of every client-output-buffer-limit directive is the following:
1132 #
1133 # client-output-buffer-limit <class> <hard limit> <soft limit> <soft seconds>
1134 #
1135 # A client is immediately disconnected once the hard limit is reached, or if
1136 # the soft limit is reached and remains reached for the specified number of
1137 # seconds (continuously).
1138 # So for instance if the hard limit is 32 megabytes and the soft limit is
1139 # 16 megabytes / 10 seconds, the client will get disconnected immediately
1140 # if the size of the output buffers reach 32 megabytes, but will also get
1141 # disconnected if the client reaches 16 megabytes and continuously overcomes
1142 # the limit for 10 seconds.
1143 #
1144 # By default normal clients are not limited because they don't receive data
1145 # without asking (in a push way), but just after a request, so only
1146 # asynchronous clients may create a scenario where data is requested faster
1147 # than it can read.
1148 #
1149 # Instead there is a default limit for pubsub and slave clients, since
1150 # subscribers and slaves receive data in a push fashion.
1151 #
1152 # Both the hard or the soft limit can be disabled by setting them to zero.
1153 client-output-buffer-limit normal 0 0 0
1154 client-output-buffer-limit slave 256mb 64mb 60
1155 client-output-buffer-limit pubsub 32mb 8mb 60
1156 
1157 # Client query buffers accumulate new commands. They are limited to a fixed
1158 # amount by default in order to avoid that a protocol desynchronization (for
1159 # instance due to a bug in the client) will lead to unbound memory usage in
1160 # the query buffer. However you can configure it here if you have very special
1161 # needs, such us huge multi/exec requests or alike.
1162 #
1163 # client-query-buffer-limit 1gb
1164 
1165 # In the Redis protocol, bulk requests, that are, elements representing single
1166 # strings, are normally limited ot 512 mb. However you can change this limit
1167 # here.
1168 #
1169 # proto-max-bulk-len 512mb
1170 
1171 # Redis calls an internal function to perform many background tasks, like
1172 # closing connections of clients in timeout, purging expired keys that are
1173 # never requested, and so forth.
1174 #
1175 # Not all tasks are performed with the same frequency, but Redis checks for
1176 # tasks to perform according to the specified "hz" value.
1177 #
1178 # By default "hz" is set to 10. Raising the value will use more CPU when
1179 # Redis is idle, but at the same time will make Redis more responsive when
1180 # there are many keys expiring at the same time, and timeouts may be
1181 # handled with more precision.
1182 #
1183 # The range is between 1 and 500, however a value over 100 is usually not
1184 # a good idea. Most users should use the default of 10 and raise this up to
1185 # 100 only in environments where very low latency is required.
1186 hz 10
1187 
1188 # When a child rewrites the AOF file, if the following option is enabled
1189 # the file will be fsync-ed every 32 MB of data generated. This is useful
1190 # in order to commit the file to the disk more incrementally and avoid
1191 # big latency spikes.
1192 aof-rewrite-incremental-fsync yes
1193 
1194 # Redis LFU eviction (see maxmemory setting) can be tuned. However it is a good
1195 # idea to start with the default settings and only change them after investigating
1196 # how to improve the performances and how the keys LFU change over time, which
1197 # is possible to inspect via the OBJECT FREQ command.
1198 #
1199 # There are two tunable parameters in the Redis LFU implementation: the
1200 # counter logarithm factor and the counter decay time. It is important to
1201 # understand what the two parameters mean before changing them.
1202 #
1203 # The LFU counter is just 8 bits per key, it's maximum value is 255, so Redis
1204 # uses a probabilistic increment with logarithmic behavior. Given the value
1205 # of the old counter, when a key is accessed, the counter is incremented in
1206 # this way:
1207 #
1208 # 1. A random number R between 0 and 1 is extracted.
1209 # 2. A probability P is calculated as 1/(old_value*lfu_log_factor+1).
1210 # 3. The counter is incremented only if R < P.
1211 #
1212 # The default lfu-log-factor is 10. This is a table of how the frequency
1213 # counter changes with a different number of accesses with different
1214 # logarithmic factors:
1215 #
1216 # +--------+------------+------------+------------+------------+------------+
1217 # | factor | 100 hits   | 1000 hits  | 100K hits  | 1M hits    | 10M hits   |
1218 # +--------+------------+------------+------------+------------+------------+
1219 # | 0      | 104        | 255        | 255        | 255        | 255        |
1220 # +--------+------------+------------+------------+------------+------------+
1221 # | 1      | 18         | 49         | 255        | 255        | 255        |
1222 # +--------+------------+------------+------------+------------+------------+
1223 # | 10     | 10         | 18         | 142        | 255        | 255        |
1224 # +--------+------------+------------+------------+------------+------------+
1225 # | 100    | 8          | 11         | 49         | 143        | 255        |
1226 # +--------+------------+------------+------------+------------+------------+
1227 #
1228 # NOTE: The above table was obtained by running the following commands:
1229 #
1230 #   redis-benchmark -n 1000000 incr foo
1231 #   redis-cli object freq foo
1232 #
1233 # NOTE 2: The counter initial value is 5 in order to give new objects a chance
1234 # to accumulate hits.
1235 #
1236 # The counter decay time is the time, in minutes, that must elapse in order
1237 # for the key counter to be divided by two (or decremented if it has a value
1238 # less <= 10).
1239 #
1240 # The default value for the lfu-decay-time is 1. A Special value of 0 means to
1241 # decay the counter every time it happens to be scanned.
1242 #
1243 # lfu-log-factor 10
1244 # lfu-decay-time 1
1245 
1246 ########################### ACTIVE DEFRAGMENTATION #######################
1247 #
1248 # WARNING THIS FEATURE IS EXPERIMENTAL. However it was stress tested
1249 # even in production and manually tested by multiple engineers for some
1250 # time.
1251 #
1252 # What is active defragmentation?
1253 # -------------------------------
1254 #
1255 # Active (online) defragmentation allows a Redis server to compact the
1256 # spaces left between small allocations and deallocations of data in memory,
1257 # thus allowing to reclaim back memory.
1258 #
1259 # Fragmentation is a natural process that happens with every allocator (but
1260 # less so with Jemalloc, fortunately) and certain workloads. Normally a server
1261 # restart is needed in order to lower the fragmentation, or at least to flush
1262 # away all the data and create it again. However thanks to this feature
1263 # implemented by Oran Agra for Redis 4.0 this process can happen at runtime
1264 # in an "hot" way, while the server is running.
1265 #
1266 # Basically when the fragmentation is over a certain level (see the
1267 # configuration options below) Redis will start to create new copies of the
1268 # values in contiguous memory regions by exploiting certain specific Jemalloc
1269 # features (in order to understand if an allocation is causing fragmentation
1270 # and to allocate it in a better place), and at the same time, will release the
1271 # old copies of the data. This process, repeated incrementally for all the keys
1272 # will cause the fragmentation to drop back to normal values.
1273 #
1274 # Important things to understand:
1275 #
1276 # 1. This feature is disabled by default, and only works if you compiled Redis
1277 #    to use the copy of Jemalloc we ship with the source code of Redis.
1278 #    This is the default with Linux builds.
1279 #
1280 # 2. You never need to enable this feature if you don't have fragmentation
1281 #    issues.
1282 #
1283 # 3. Once you experience fragmentation, you can enable this feature when
1284 #    needed with the command "CONFIG SET activedefrag yes".
1285 #
1286 # The configuration parameters are able to fine tune the behavior of the
1287 # defragmentation process. If you are not sure about what they mean it is
1288 # a good idea to leave the defaults untouched.
1289 
1290 # Enabled active defragmentation
1291 # activedefrag yes
1292 
1293 # Minimum amount of fragmentation waste to start active defrag
1294 # active-defrag-ignore-bytes 100mb
1295 
1296 # Minimum percentage of fragmentation to start active defrag
1297 # active-defrag-threshold-lower 10
1298 
1299 # Maximum percentage of fragmentation at which we use maximum effort
1300 # active-defrag-threshold-upper 100
1301 
1302 # Minimal effort for defrag in CPU percentage
1303 # active-defrag-cycle-min 25
1304 
1305 # Maximal effort for defrag in CPU percentage
1306 # active-defrag-cycle-max 75
View Code
剩下的配置文件内容,只需要参考redis6381.conf,把其中涉及到6381修改为自己对应的6382、6383、6384...就可以了。
1.2、 分别启动这些Redis数据库
(1)启动6个redis示例:
  ./redis-server redis6381.conf
  ./redis-server redis6382.conf
  ./redis-server redis6383.conf
  ./redis-server redis6384.conf
  ./redis-server redis6385.conf
  ./redis-server redis6386.conf
(2)执行命令:ps -ef|grep redis
  501 12169     1   0  8:11上午 ??         0:00.03 ./redis-server 127.0.0.1:6381 [cluster]
  501 12171     1   0  8:11上午 ??         0:00.02 ./redis-server 127.0.0.1:6382 [cluster]
  501 12173     1   0  8:11上午 ??         0:00.02 ./redis-server 127.0.0.1:6383 [cluster]
  501 12175     1   0  8:11上午 ??         0:00.02 ./redis-server 127.0.0.1:6384 [cluster]
  501 12177     1   0  8:11上午 ??         0:00.01 ./redis-server 127.0.0.1:6385 [cluster]
  501 12179     1   0  8:11上午 ??         0:00.01 ./redis-server 127.0.0.1:6386 [cluster]
  501 12181 11792   0  8:11上午 ttys004    0:00.01 grep redis
(3)可以用cluster info来进行查看,目前这6个redis实例是孤立的,它们之间还没有建立集群的关系
127.0.0.1:6381机器上执行命令:cluster info
127.0.0.1:6382机器上执行命令:cluster info

1.3、 连接节点,使用cluster meet,把所有的数据库都放到一个集群中来
在127.0.0.1:6381机器上执行如下命令:
1.4、 可以通过cluster info,或者cluster nodes查看信息
在127.0.0.1:6381机器上执行 cluster info、cluster nodes。(在其它的机器上执行也是一样的效果)
1.5、 设置部分数据库为slave,使用cluster replicate
在127.0.0.1:6384机器上执行:cluster replicate 5f0fa9ce5b911e4ed2e7230929a9a5951a58d48b
在127.0.0.1:6385机器上执行:cluster replicate 6a80d0d12cbb927e6efffb417a4fe15028edf33b
在127.0.0.1:6386机器上执行:cluster replicate 7d09251534236145bea1aac58aa095b789bf857d
1.6、 分配插槽
使用cluster addSlots,这个命令目前只能一个一个加,如果要加区间的话,就得客户端编写代码来循环添加了。
有个实用的技巧:把所有的Redis停下来,然后直接修改node的配置文件,只需要配置master的数据库就可以了,然后再重启数据库。
nodes-6381.conf的配置如下:(其它的5个文件也照着这样去配置)

重写启动6个redis数据库实例

  ./redis-server redis6381.conf
  ./redis-server redis6382.conf
  ./redis-server redis6383.conf
  ./redis-server redis6384.conf
  ./redis-server redis6385.conf
  ./redis-server redis6386.conf

 可以使用cluster keyslot key来查看每个key应该放到哪个插槽里面,如下:

1.7、 通过cluster info查看集群信息,如果显示ok,那就是可以使用了
 
 
 
 
 
 
 
 
 
 
 
 
 

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转载自www.cnblogs.com/xinhuaxuan/p/9363901.html