cd /etc/rc.d vi rc.local chmod 755 rc.local echo never > /sys/kernel/mm/transparent_hugepage/enabled 啓動警告問題的解決
redis.conf redis配置文件java
daemonize yes Redis在後臺運行linux
/usr/software/redis/redis-3.0.1/utils/redis_init_script 腳本參考redis
vim /etc/init.d/redis 編寫腳本數據庫
PATH=/usr/local/redis-3.2.0/src REDISPORT=6379 EXEC=/usr/local/redis-3.2.0/src/redis-server REDIS_CLI=/usr/local/redis-3.2.0/src/redis-cli PIDFILE=/var/run/redis.pid CONF="/usr/local/redis-3.2.0/redis.conf" case "$1" in start) if [ -f $PIDFILE ] then echo "$PIDFILE exists" else echo "start redis server.." $EXEC $CONF fi #$? 就是輸出上次腳本的退出碼。若是是0說明上次腳本執行成功,若是非0說明上次腳本執行失敗。 if [ "$?"="0" ] then echo "redis is running" fi ;; stop) if [ ! -f $PIDFILE ] then echo "$PIDFILE exists" else PID=$(cat $PIDFILE) echo "stop" $REDIS_CLI -p $REDISPORT SHUTDOWN while [ -x $PIDFILE ] do echo "waiting redis shutdown" sleep 1 done echo "redis stopped" fi ;; restart|force-reload) ${0} stop ${0} start ;; *) exit 1 esac
相關命令vim
chmod +x /etc/init.d/redis 添加執行權限 update-rc.d redis defaults 設置開機運行 或 chkconfig redis on 或 vim /etc/rc.local /etc/init.d/redis start exit 0 update-rc.d -f redis remove 移除開機啓動 /etc/init.d/redis start 嘗試啓動或中止redis /etc/init.d/redis stop ps -ef | grep redis 查看redis是否運行
Redis.conf配置說明promise
-e filename 若是 filename存在,則爲真 -d filename 若是 filename爲目錄,則爲真 -f filename 若是 filename爲常規文件,則爲真 -L filename 若是 filename爲符號連接,則爲真 -r filename 若是 filename可讀,則爲真 -w filename 若是 filename可寫,則爲真 -x filename 若是 filename可執行,則爲真 -s filename 若是文件長度不爲0,則爲真 -h filename 若是文件是軟連接,則爲真 filename1 -nt filename2 若是 filename1比 filename2新,則爲真。 filename1 -ot filename2 若是 filename1比 filename2舊,則爲真。 -eq 等於 -ne 不等於 -gt 大於 -ge 大於等於 -lt 小於 -le 小於等於 至於!號那就是取非
# By default Redis does not run as a daemon. Use 'yes' if you need it. # Note that Redis will write a pid file in /var/run/redis.pid when daemonized. #Redis默認不是以守護進程的方式運行,能夠經過該配置項修改,使用yes啓用守護進程 daemonize no # When running daemonized, Redis writes a pid file in /var/run/redis.pid by # default. You can specify a custom pid file location here. #當 Redis 以守護進程的方式運行的時候,Redis 默認會把 pid 文件放在/var/run/redis.pid #可配置到其餘地址,當運行多個 redis 服務時,須要指定不一樣的 pid 文件和端口 pidfile /var/run/redis.pid # Accept connections on the specified port, default is 6379. # If port 0 is specified Redis will not listen on a TCP socket. #端口 port 6379 # If you want you can bind a single interface, if the bind option is not # specified all the interfaces will listen for incoming connections. #指定Redis可接收請求的IP地址,不設置將處理全部請求,建議生產環境中設置 # bind 127.0.0.1 # Close the connection after a client is idle for N seconds (0 to disable) #客戶端鏈接的超時時間,單位爲秒,超時後會關閉鏈接 timeout 0 # Set server verbosity to 'debug' # it can be one of: # debug (a lot of information, useful for development/testing) # verbose (many rarely useful info, but not a mess like the debug level) # notice (moderately verbose, what you want in production probably) # warning (only very important / critical messages are logged) #日誌記錄等級,4個可選值 loglevel notice # Specify the log file name. Also 'stdout' can be used to force # Redis to log on the standard output. Note that if you use standard # output for logging but daemonize, logs will be sent to /dev/null #配置 log 文件地址,默認打印在命令行終端的窗口上,也可設爲/dev/null屏蔽日誌、 logfile stdout # Set the number of databases. The default database is DB 0, you can select # a different one on a per-connection basis using SELECT where # dbid is a number between 0 and 'databases'-1 #設置數據庫的個數,可使用 SELECT 命令來切換數據庫。 databases 16 # # Save the DB on disk: # # save # # Will save the DB if both the given number of seconds and the given # number of write operations against the DB occurred. # # In the example below the behaviour will be to save: # after 900 sec (15 min) if at least 1 key changed # after 300 sec (5 min) if at least 10 keys changed # after 60 sec if at least 10000 keys changed # # Note: you can disable saving at all commenting all the "save" lines. #設置 Redis 進行數據庫鏡像的頻率。保存數據到disk的策略 #900秒以內有1個keys發生變化時 #30秒以內有10個keys發生變化時 #60秒以內有10000個keys發生變化時 save 900 1 save 300 10 save 60 10000 # Compress string objects using LZF when dump .rdb databases? # For default that's set to 'yes' as it's almost always a win. # If you want to save some CPU in the saving child set it to 'no' but # the dataset will likely be bigger if you have compressible values or keys. #在進行鏡像備份時,是否進行壓縮 rdbcompression yes # The filename where to dump the DB #鏡像備份文件的文件名 dbfilename dump.rdb # The working directory. # # The DB will be written inside this directory, with the filename specified # above using the 'dbfilename' configuration directive. # # Also the Append Only File will be created inside this directory. # # Note that you must specify a directory here, not a file name. #數據庫鏡像備份的文件放置的路徑 #路徑跟文件名分開配置是由於 Redis 備份時,先會將當前數據庫的狀態寫入到一個臨時文件 #等備份完成時,再把該臨時文件替換爲上面所指定的文件 #而臨時文件和上面所配置的備份文件都會放在這個指定的路徑當中 #默認值爲 ./ dir /var/lib/redis/ # Master-Slave replication. Use slaveof to make a Redis instance a copy of # another Redis server. Note that the configuration is local to the slave # 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. #設置該數據庫爲其餘數據庫的從數據庫 #slaveof <masterip> <masterport> 當本機爲從服務時,設置主服務的IP及端口 # slaveof # If the master is password protected (using the "requirepass" configuration # directive below) it is possible to tell the slave to authenticate before # starting the replication synchronization process, otherwise the master will # refuse the slave request. #指定與主數據庫鏈接時須要的密碼驗證 #masterauth <master-password> 當本機爲從服務時,設置主服務的鏈接密碼 # masterauth # 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. #當slave丟失與master的鏈接時,或slave仍然在於master進行數據同步時(未與master保持一致) #slave可有兩種方式來響應客戶端請求: #1)若是 slave-serve-stale-data 設置成 'yes'(默認),slave仍會響應客戶端請求,此時可能會有問題 #2)若是 slave-serve-stale-data 設置成 'no',slave會返回"SYNC with master in progress"錯誤信息,但 INFO 和SLAVEOF命令除外。 slave-serve-stale-data yes # Require clients to issue AUTH before processing any other # commands. This might be useful in environments in which you do not trust # others with access to the host running redis-server. # # This should stay commented out for backward compatibility and because most # people do not need auth (e.g. they run their own servers). # # Warning: since Redis is pretty fast an outside user can try up to # 150k passwords per second against a good box. This means that you should # use a very strong password otherwise it will be very easy to break. #設置客戶端鏈接後進行任何其餘指定前須要使用的密碼 #redis速度至關快,一個外部用戶在一秒鐘進行150K次密碼嘗試,需指定強大的密碼來防止暴力破解 # requirepass foobared # Set the max number of connected clients at the same time. By default there # is no limit, and it's up to the number of file descriptors the Redis process # is able to open. The special value '0' means no limits. # Once the limit is reached Redis will close all the new connections sending # an error 'max number of clients reached'. #限制同時鏈接的客戶數量。 #當鏈接數超過這個值時,redis 將再也不接收其餘鏈接請求,客戶端嘗試鏈接時將收到 error 信息 # 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 # accordingly to the eviction policy selected (see maxmemmory-policy). # # If Redis can't remove keys according to the policy, or if the policy is # set to 'noeviction', Redis will start to reply with errors to commands # that would use more memory, like SET, LPUSH, and so on, and will continue # to reply to read-only commands like GET. # # This option is usually useful when using Redis as an LRU cache, or to set # an hard memory limit for an instance (using the 'noeviction' policy). # # WARNING: If you have slaves attached to an instance with maxmemory on, # the size of the output buffers needed to feed the slaves are subtracted # from the used memory count, so that network problems / resyncs will # not trigger a loop where keys are evicted, and in turn the output # buffer of slaves is full with DELs of keys evicted triggering the deletion # of more keys, and so forth until the database is completely emptied. # # In short... if you have slaves attached it is suggested that you set a lower # limit for maxmemory so that there is some free RAM on the system for slave # output buffers (but this is not needed if the policy is 'noeviction'). #設置redis可以使用的最大內存。 #達到最大內存設置後,Redis會先嚐試清除已到期或即將到期的Key(設置過expire信息的key) #在刪除時,按照過時時間進行刪除,最先將要被過時的key將最早被刪除 #若是已到期或即將到期的key刪光,仍進行set操做,那麼將返回錯誤 #此時redis將再也不接收寫請求,只接收get請求。 #maxmemory的設置比較適合於把redis看成於相似memcached 的緩存來使用 # maxmemory <bytes> # By default Redis asynchronously dumps the dataset on disk. If you can live # with the idea that the latest records will be lost if something like a crash # happens this is the preferred way to run Redis. If instead you care a lot # about your data and don't want to that a single record can get lost you should # enable the append only mode: when this mode is enabled Redis will append # every write operation received in the file appendonly.aof. This file will # be read on startup in order to rebuild the full dataset in memory. # # 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. # # IMPORTANT: Check the BGREWRITEAOF to check how to rewrite the append # log file in background when it gets too big. #redis 默認每次更新操做後會在後臺異步的把數據庫鏡像備份到磁盤,但該備份很是耗時,且備份不宜太頻繁 #redis 同步數據文件是按上面save條件來同步的 #若是發生諸如拉閘限電、拔插頭等情況,那麼將形成比較大範圍的數據丟失 #因此redis提供了另一種更加高效的數據庫備份及災難恢復方式 #開啓append only 模式後,redis 將每一次寫操做請求都追加到appendonly.aof 文件中 #redis從新啓動時,會從該文件恢復出以前的狀態。 #但可能會形成 appendonly.aof 文件過大,因此redis支持BGREWRITEAOF 指令,對appendonly.aof從新整理 appendonly no # The name of the append only file (default: "appendonly.aof") ##更新日誌文件名,默認值爲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. # # Redis supports three different modes: # # no: don't fsync, just let the OS flush the data when it wants. Faster. # always: fsync after every write to the append only log . Slow, Safest. # everysec: fsync only if one second passed since the last fsync. Compromise. # # The default is "everysec" that's usually the right compromise between # speed and data safety. It's up to you to understand if you can relax this to # "no" that will will let the operating system flush the output buffer when # it wants, for better performances (but if you can live with the idea of # some data loss consider the default persistence mode that's snapshotting), # or on the contrary, use "always" that's very slow but a bit safer than # everysec. # # If unsure, use "everysec". #設置對 appendonly.aof 文件進行同步的頻率 #always 表示每次有寫操做都進行同步,everysec 表示對寫操做進行累積,每秒同步一次。 #no表示等操做系統進行數據緩存同步到磁盤,都進行同步,everysec 表示對寫操做進行累積,每秒同步一次 # appendfsync always appendfsync everysec # appendfsync no # 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. # # To enable VM just set 'vm-enabled' to yes, and set the following three # VM parameters accordingly to your needs. #是否開啓虛擬內存支持。 #redis 是一個內存數據庫,當內存滿時,沒法接收新的寫請求,因此在redis2.0後,提供了虛擬內存的支持 #但須要注意的,redis 全部的key都會放在內存中,在內存不夠時,只把value 值放入交換區 #雖使用虛擬內存,但性能基本不受影響,須要注意的是要把vm-max-memory設置到足夠來放下全部的key 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. # # The best kind of storage for the Redis swap file (that's accessed at random) # is a Solid State Disk (SSD). # # *** 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. #設置虛擬內存的交換文件路徑,不可多個Redis實例共享 vm-swap-file /tmp/redis.swap # vm-max-memory configures the VM to use at max the specified amount of # RAM. Everything that deos not fit will be swapped on disk *if* possible, that # is, if there is still enough contiguous space in the swap file. # # 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. #設置開啓虛擬內存後,redis將使用的最大物理內存大小。 #默認爲0,redis將把他全部能放到交換文件的都放到交換文件中,以儘可能少的使用物理內存 #即當vm-max-memory設置爲0的時候,實際上是全部value都存在於磁盤 #在生產環境下,須要根據實際狀況設置該值,最好不要使用默認的 0 vm-max-memory 0 # Redis swap files is split into pages. An object can be saved using multiple # contiguous pages, but pages can't be shared between different objects. # So if your page is too big, small objects swapped out on disk will waste # a lot of space. If you page is too small, there is less space in the swap # file (assuming you configured the same number of total swap file pages). # # If you use a lot of small objects, use a page size of 64 or 32 bytes. # If you use a lot of big objects, use a bigger page size. # If unsure, use the default :) #設置虛擬內存的頁大小 若是 value 值比較大,如要在 value 中放置博客、新聞之類的全部文章內容,就設大一點 vm-page-size 32 # Number of total memory pages in the swap file. # Given that the page table (a bitmap of free/used pages) is taken in memory, # every 8 pages on disk will consume 1 byte of RAM. # # The total swap size is 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. #設置交換文件的總的 page 數量 #注意page table信息是放在物理內存中,每8個page 就會佔據RAM中的 1 個 byte #總的虛擬內存大小 = vm-page-size * vm-pages 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. # # The special value of 0 turn off threaded I/O and enables the blocking # Virtual Memory implementation. #設置 VM IO 同時使用的線程數量。 vm-max-threads 4 # 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. #redis 2.0後引入了 hash 數據結構。 #hash 中包含超過指定元素個數而且最大的元素當沒有超過臨界時,hash 將以zipmap來存儲 #zipmap又稱爲 small hash,可大大減小內存的使用 hash-max-zipmap-entries 512 hash-max-zipmap-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. # # use "activerehashing yes" if you don't have such hard requirements but # want to free memory asap when possible. #是否重置Hash表 #設置成yes後redis將每100毫秒使用1毫秒CPU時間來對redis的hash表從新hash,可下降內存的使用 #當使用場景有較爲嚴格的實時性需求,不能接受Redis時不時的對請求有2毫秒的延遲的話,把這項配置爲no。 #若是沒有這麼嚴格的實時性要求,能夠設置爲 yes,以便可以儘量快的釋放內存 activerehashing yes Redis官方文檔對VM的使用提出了一些建議: 當key很小而value很大時,使用VM的效果會比較好.由於這樣節約的內存比較大 當key不小時,能夠考慮使用一些很是方法將很大的key變成很大的value,如可將key,value組合成一個新的value 最好使用linux ext3 等對稀疏文件支持比較好的文件系統保存你的swap文件 vm-max-threads參數可設置訪問swap文件的線程數,最好不要超過機器的核數;設置爲0則全部對swap文件的操做都是串行的,可能會形成比較長時間的延遲,可是對數據完整性有很好的保證 redis數據存儲 redis的存儲分爲內存存儲、磁盤存儲和log文件三部分,配置文件中有三個參數對其進行配置。 save seconds updates,save配置,指出在多長時間內,有多少次更新操做,就將數據同步到數據文件。可多個條件配合,默認配置了三個條件。 appendonly yes/no ,appendonly配置,指出是否在每次更新操做後進行日誌記錄,若是不開啓,可能會在斷電時致使一段時間內的數據丟失。由於redis自己同步數據文件是按上面的save條件來同步的,因此有的數據會在一段時間內只存在於內存中。 appendfsync no/always/everysec ,appendfsync配置,no表示等操做系統進行數據緩存同步到磁盤,always表示每次更新操做後手動調用fsync()將數據寫到磁盤,everysec表示每秒同步一次。