Redis預設設定檔redis.conf詳解

標籤：

# Redis設定檔範例# Note on units: when memory size is needed, it is possible to specifiy# it in the usual form of 1k 5GB 4M and so forth:## 1k => 1000 bytes# 1kb => 1024 bytes# 1m => 1000000 bytes# 1mb => 1024*1024 bytes# 1g => 1000000000 bytes# 1gb => 1024*1024*1024 bytes## units are case insensitive so 1GB 1Gb 1gB are all the same.# Redis預設不是以守護進程的方式運行，可以通過該配置項修改，使用yes啟用守護進程# 啟用守護進程後，Redis會把pid寫到一個pidfile中，在/var/run/redis.piddaemonize no# 當Redis以守護進程方式運行時，Redis預設會把pid寫入/var/run/redis.pid檔案，可以通過pidfile指定pidfile /var/run/redis.pid# 指定Redis監聽連接埠，預設連接埠為6379# 如果指定0連接埠，表示Redis不監聽TCP串連port 6379# 綁定的主機地址# 你可以綁定單一介面，如果沒有綁定，所有介面都會監聽到來的串連# bind 127.0.0.1# Specify the path for the unix socket that will be used to listen for# incoming connections. There is no default, so Redis will not listen# on a unix socket when not specified.## unixsocket /tmp/redis.sock# unixsocketperm 755# 當用戶端閑置多長時間後關閉串連，如果指定為0，表示關閉該功能timeout 0# 指定日誌記錄層級，Redis總共支援四個層級：debug、verbose、notice、warning，預設為verbose# debug (很多資訊, 對開發／測試比較有用)# verbose (many rarely useful info, but not a mess like the debug level)# notice (moderately verbose, what you want in production probably)# warning (only very important / critical messages are logged)loglevel verbose# 日誌記錄方式，預設為標準輸出，如果配置為redis為守護進程方式運行，而這裡又配置為標準輸出，則日誌將會發送給/dev/nulllogfile stdout# To enable logging to the system logger, just set 'syslog-enabled' to yes,# and optionally update the other syslog parameters to suit your needs.# syslog-enabled no# Specify the syslog identity.# syslog-ident redis# Specify the syslog facility.  Must be USER or between LOCAL0-LOCAL7.# syslog-facility local0# 設定資料庫的數量，預設資料庫為0，可以使用select <dbid>命令在串連上指定資料庫id# dbid是從0到‘databases’-1的數目databases 16################################ SNAPSHOTTING  ################################## 指定在多長時間內，有多少次更新操作，就將資料同步到資料檔案，可以多個條件配合# Save the DB on disk:##   save <seconds> <changes>##   Will save the DB if both the given number of seconds and the given#   number of write operations against the DB occurred.##   滿足以下條件將會同步資料:#   900秒（15分鐘）內有1個更改#   300秒（5分鐘）內有10個更改#   60秒內有10000個更改#   Note: 可以把所有“save”行注釋掉，這樣就取消同步操作了save 900 1save 300 10save 60 10000# 指定儲存至本機資料庫時是否壓縮資料，預設為yes，Redis採用LZF壓縮，如果為了節省CPU時間，可以關閉該選項，但會導致資料庫檔案變的巨大rdbcompression yes# 指定本機資料庫檔案名稱，預設值為dump.rdbdbfilename dump.rdb# 工作目錄.# 指定本機資料庫存放目錄，檔案名稱由上一個dbfilename配置項指定# # Also the Append Only File will be created inside this directory.# # 注意，這裡只能指定一個目錄，不能指定檔案名稱dir ./################################# REPLICATION ################################## 主從複製。使用slaveof從 Redis伺服器複製一個Redis執行個體。注意，該配置僅限於當前slave有效# so for example it is possible to configure the slave to save the DB with a# different interval, or to listen to another port, and so on.# 設定當本機為slav服務時，設定master服務的ip地址及連接埠，在Redis啟動時，它會自動從master進行資料同步# slaveof <masterip> <masterport># 當master服務設定了密碼保護時，slav服務串連master的密碼# 下文的“requirepass”配置項可以指定密碼# masterauth <master-password># When a slave lost the connection with the master, or when the replication# is still in progress, the slave can act in two different ways:## 1) if slave-serve-stale-data is set to 'yes' (the default) the slave will#    still reply to client requests, possibly with out of data data, or the#    data set may just be empty if this is the first synchronization.## 2) if slave-serve-stale data is set to 'no' the slave will reply with#    an error "SYNC with master in progress" to all the kind of commands#    but to INFO and SLAVEOF.#slave-serve-stale-data yes# Slaves send PINGs to server in a predefined interval. It's possible to change# this interval with the repl_ping_slave_period option. The default value is 10# seconds.## repl-ping-slave-period 10# The following option sets a timeout for both Bulk transfer I/O timeout and# master data or ping response timeout. The default value is 60 seconds.## It is important to make sure that this value is greater than the value# specified for repl-ping-slave-period otherwise a timeout will be detected# every time there is low traffic between the master and the slave.## repl-timeout 60################################## SECURITY #################################### Warning: since Redis is pretty fast an outside user can try up to# 150k passwords per second against a good box. This means that you should# use a very strong password otherwise it will be very easy to break.# 設定Redis串連密碼，如果配置了串連密碼，用戶端在串連Redis時需要通過auth <password>命令提供密碼，預設關閉# requirepass foobared# Command renaming.## It is possilbe to change the name of dangerous commands in a shared# environment. For instance the CONFIG command may be renamed into something# of hard to guess so that it will be still available for internal-use# tools but not available for general clients.## Example:## rename-command CONFIG b840fc02d524045429941cc15f59e41cb7be6c52## It is also possilbe to completely kill a command renaming it into# an empty string:## rename-command CONFIG ""################################### LIMITS ##################################### 設定同一時間最大用戶端串連數，預設無限制，Redis可以同時開啟的用戶端串連數為Redis進程可以開啟的最大檔案描述符數，# 如果設定maxclients 0，表示不作限制。當用戶端串連數到達限制時，Redis會關閉新的串連並向用戶端返回max Number of clients reached錯誤資訊# maxclients 128# Don't use more memory than the specified amount of bytes.# When the memory limit is reached Redis will try to remove keys with an# EXPIRE set. It will try to start freeing keys that are going to expire# in little time and preserve keys with a longer time to live.# Redis will also try to remove objects from free lists if possible.## If all this fails, Redis will start to reply with errors to commands# that will use more memory, like SET, LPUSH, and so on, and will continue# to reply to most read-only commands like GET.## WARNING: maxmemory can be a good idea mainly if you want to use Redis as a# 'state' server or cache, not as a real DB. When Redis is used as a real# database the memory usage will grow over the weeks, it will be obvious if# it is going to use too much memory in the long run, and you'll have the time# to upgrade. With maxmemory after the limit is reached you'll start to get# errors for write operations, and this may even lead to DB inconsistency.# 指定Redis最大記憶體限制，Redis在啟動時會把資料載入到記憶體中，達到最大記憶體後，Redis會先嘗試清除已到期或即將到期的Key，# 當此方法處理後，仍然到達最大記憶體設定，將無法再進行寫入操作，但仍然可以進行讀取操作。# Redis新的vm機制，會把Key存放記憶體，Value會存放在swap區# maxmemory <bytes># MAXMEMORY POLICY: how Redis will select what to remove when maxmemory# is reached? You can select among five behavior:# # volatile-lru -> remove the key with an expire set using an LRU algorithm# allkeys-lru -> remove any key accordingly to the LRU algorithm# volatile-random -> remove a random key with an expire set# allkeys->random -> remove a random key, any key# volatile-ttl -> remove the key with the nearest expire time (minor TTL)# noeviction -> don't expire at all, just return an error on write operations# # Note: with all the kind of policies, Redis will return an error on write#       operations, when there are not suitable keys for eviction.##       At the date of writing this commands are: set setnx setex append#       incr decr rpush lpush rpushx lpushx linsert lset rpoplpush sadd#       sinter sinterstore sunion sunionstore sdiff sdiffstore zadd zincrby#       zunionstore zinterstore hset hsetnx hmset hincrby incrby decrby#       getset mset msetnx exec sort## The default is:## maxmemory-policy volatile-lru# LRU and minimal TTL algorithms are not precise algorithms but approximated# algorithms (in order to save memory), so you can select as well the sample# size to check. For instance for default Redis will check three keys and# pick the one that was used less recently, you can change the sample size# using the following configuration directive.## maxmemory-samples 3############################## APPEND ONLY MODE ################################ # Note that you can have both the async dumps and the append only file if you# like (you have to comment the "save" statements above to disable the dumps).# Still if append only mode is enabled Redis will load the data from the# log file at startup ignoring the dump.rdb file.# 指定是否在每次更新操作後進行日誌記錄，Redis在預設情況下是非同步把資料寫入磁碟，如果不開啟，可能會在斷電時導致一段時間內的資料丟失。# 因為redis本身同步資料檔案是按上面save條件來同步的，所以有的資料會在一段時間內只存在於記憶體中。預設為no# IMPORTANT: Check the BGREWRITEAOF to check how to rewrite the append# log file in background when it gets too big.appendonly no# 指定更新記錄檔名，預設為appendonly.aof# appendfilename appendonly.aof# The fsync() call tells the Operating System to actually write data on disk# instead to wait for more data in the output buffer. Some OS will really flush # data on disk, some other OS will just try to do it ASAP.# 指定更新日誌條件，共有3個可選值：# no:表示等作業系統進行資料緩衝同步到磁碟（快）# always:表示每次更新操作後手動調用fsync()將資料寫到磁碟（慢，安全）# everysec:表示每秒同步一次（折衷，預設值）appendfsync everysec# appendfsync no# When the AOF fsync policy is set to always or everysec, and a background# saving process (a background save or AOF log background rewriting) is# performing a lot of I/O against the disk, in some Linux configurations# Redis may block too long on the fsync() call. Note that there is no fix for# this currently, as even performing fsync in a different thread will block# our synchronous write(2) call.## In order to mitigate this problem it's possible to use the following option# that will prevent fsync() from being called in the main process while a# BGSAVE or BGREWRITEAOF is in progress.## This means that while another child is saving the durability of Redis is# the same as "appendfsync none", that in pratical terms means that it is# possible to lost up to 30 seconds of log in the worst scenario (with the# default Linux settings).# # If you have latency problems turn this to "yes". Otherwise leave it as# "no" that is the safest pick from the point of view of durability.no-appendfsync-on-rewrite no# Automatic rewrite of the append only file.# Redis is able to automatically rewrite the log file implicitly calling# BGREWRITEAOF when the AOF log size will growth by the specified percentage.# # This is how it works: Redis remembers the size of the AOF file after the# latest rewrite (or if no rewrite happened since the restart, the size of# the AOF at startup is used).## This base size is compared to the current size. If the current size is# bigger than the specified percentage, the rewrite is triggered. Also# you need to specify a minimal size for the AOF file to be rewritten, this# is useful to avoid rewriting the AOF file even if the percentage increase# is reached but it is still pretty small.## Specify a precentage of zero in order to disable the automatic AOF# rewrite feature.auto-aof-rewrite-percentage 100auto-aof-rewrite-min-size 64mb################################## SLOW LOG #################################### The Redis Slow Log is a system to log queries that exceeded a specified# execution time. The execution time does not include the I/O operations# like talking with the client, sending the reply and so forth,# but just the time needed to actually execute the command (this is the only# stage of command execution where the thread is blocked and can not serve# other requests in the meantime).# # You can configure the slow log with two parameters: one tells Redis# what is the execution time, in microseconds, to exceed in order for the# command to get logged, and the other parameter is the length of the# slow log. When a new command is logged the oldest one is removed from the# queue of logged commands.# The following time is expressed in microseconds, so 1000000 is equivalent# to one second. Note that a negative number disables the slow log, while# a value of zero forces the logging of every command.slowlog-log-slower-than 10000# There is no limit to this length. Just be aware that it will consume memory.# You can reclaim memory used by the slow log with SLOWLOG RESET.slowlog-max-len 1024################################ VIRTUAL MEMORY ################################## WARNING! Virtual Memory is deprecated in Redis 2.4### The use of Virtual Memory is strongly discouraged.### WARNING! Virtual Memory is deprecated in Redis 2.4### The use of Virtual Memory is strongly discouraged.# Virtual Memory allows Redis to work with datasets bigger than the actual# amount of RAM needed to hold the whole dataset in memory.# In order to do so very used keys are taken in memory while the other keys# are swapped into a swap file, similarly to what operating systems do# with memory pages.# 指定是否啟用虛擬記憶體機制，預設值為no，# VM機制將資料分頁存放，由Redis將訪問量較少的頁即冷資料swap到磁碟上，訪問多的頁面由磁碟自動換出到記憶體中# 把vm-enabled設定為yes，根據需要設定好接下來的三個VM參數，就可以啟動VM了vm-enabled no# vm-enabled yes# This is the path of the Redis swap file. As you can guess, swap files# can't be shared by different Redis instances, so make sure to use a swap# file for every redis process you are running. Redis will complain if the# swap file is already in use.## Redis分頁檔最好的儲存是SSD（固態硬碟）# 虛擬記憶體檔案路徑，預設值為/tmp/redis.swap，不可多個Redis執行個體共用# *** WARNING *** if you are using a shared hosting the default of putting# the swap file under /tmp is not secure. Create a dir with access granted# only to Redis user and configure Redis to create the swap file there.vm-swap-file /tmp/redis.swap# With vm-max-memory 0 the system will swap everything it can. Not a good# default, just specify the max amount of RAM you can in bytes, but it's# better to leave some margin. For instance specify an amount of RAM# that's more or less between 60 and 80% of your free RAM.# 將所有大於vm-max-memory的資料存入虛擬記憶體，無論vm-max-memory設定多少，所有索引資料都是記憶體儲存的（Redis的索引資料就是keys）# 也就是說當vm-max-memory設定為0的時候，其實是所有value都存在於磁碟。預設值為0vm-max-memory 0# Redis swap檔案分成了很多的page，一個對象可以儲存在多個page上面，但一個page上不能被多個對象共用，vm-page-size是要根據儲存的資料大小來設定的。# 建議如果儲存很多小對象，page大小最後設定為32或64bytes；如果儲存很大的對象，則可以使用更大的page，如果不確定，就使用預設值vm-page-size 32# 設定swap檔案中的page數量由於頁表（一種表示頁面空閑或使用的bitmap）是存放在記憶體中的，在磁碟上每8個pages將消耗1byte的記憶體# swap空間總容量為 vm-page-size * vm-pages## With the default of 32-bytes memory pages and 134217728 pages Redis will# use a 4 GB swap file, that will use 16 MB of RAM for the page table.## It's better to use the smallest acceptable value for your application,# but the default is large in order to work in most conditions.vm-pages 134217728# Max number of VM I/O threads running at the same time.# This threads are used to read/write data from/to swap file, since they# also encode and decode objects from disk to memory or the reverse, a bigger# number of threads can help with big objects even if they can't help with# I/O itself as the physical device may not be able to couple with many# reads/writes operations at the same time.# 設定訪問swap檔案的I/O線程數，最後不要超過機器的核心數，如果設定為0，那麼所有對swap檔案的操作都是串列的，可能會造成比較長時間的延遲，預設值為4vm-max-threads 4############################### ADVANCED CONFIG ################################ Hashes are encoded in a special way (much more memory efficient) when they# have at max a given numer of elements, and the biggest element does not# exceed a given threshold. You can configure this limits with the following# configuration directives.# 指定在超過一定的數量或者最大的元素超過某一臨界值時，採用一種特殊的雜湊演算法hash-max-zipmap-entries 512hash-max-zipmap-value 64# Similarly to hashes, small lists are also encoded in a special way in order# to save a lot of space. The special representation is only used when# you are under the following limits:list-max-ziplist-entries 512list-max-ziplist-value 64# Sets have a special encoding in just one case: when a set is composed# of just strings that happens to be integers in radix 10 in the range# of 64 bit signed integers.# The following configuration setting sets the limit in the size of the# set in order to use this special memory saving encoding.set-max-intset-entries 512# Similarly to hashes and lists, sorted sets are also specially encoded in# order to save a lot of space. This encoding is only used when the length and# elements of a sorted set are below the following limits:zset-max-ziplist-entries 128zset-max-ziplist-value 64# Active rehashing uses 1 millisecond every 100 milliseconds of CPU time in# order to help rehashing the main Redis hash table (the one mapping top-level# keys to values). The hash table implementation redis uses (see dict.c)# performs a lazy rehashing: the more operation you run into an hash table# that is rhashing, the more rehashing "steps" are performed, so if the# server is idle the rehashing is never complete and some more memory is used# by the hash table.# # The default is to use this millisecond 10 times every second in order to# active rehashing the main dictionaries, freeing memory when possible.## If unsure:# use "activerehashing no" if you have hard latency requirements and it is# not a good thing in your environment that Redis can reply form time to time# to queries with 2 milliseconds delay.# 指定是否啟用重設雜湊，預設為開啟activerehashing yes################################## INCLUDES #################################### 指定包含其他的設定檔，可以在同一主機上多個Redis執行個體之間使用同一份設定檔，而同時各執行個體又擁有自己的特定設定檔# include /path/to/local.conf# include /path/to/other.conf

Redis預設設定檔redis.conf詳解