NoSql redis windows下的環境搭建

Redis 簡介

Redis 是徹底開源免費的，遵照BSD協議，是一個高性能的key-value數據庫。

 

Redis 與其餘 key - value 緩存產品有如下三個特色：

• Redis支持數據的持久化，能夠將內存中的數據保存在磁盤中，重啓的時候能夠再次加載進行使用。
• Redis不只僅支持簡單的key-value類型的數據，同時還提供list，set，zset，hash等數據結構的存儲。
• Redis支持數據的備份，即master-slave模式的數據備份。

Redis 優點

• 性能極高 – Redis能讀的速度是110000次/s,寫的速度是81000次/s 。
• 豐富的數據類型 – Redis支持二進制案例的 Strings, Lists, Hashes, Sets 及 Ordered Sets 數據類型操做。
• 原子 – Redis的全部操做都是原子性的，同時Redis還支持對幾個操做全並後的原子性執行。
• 豐富的特性 – Redis還支持 publish/subscribe, 通知, key 過時等等特性。

（一）、下載Redis

下載地址：https://github.com/dmajkic/Redis/downloads 下載下來的包裏有兩個，一個是32位的，一個是64位的。根據本身的實情狀況選擇，個人是64bit；

（一）、安裝步驟

1. 在D盤新建文件夾【redis】，右鍵解壓Redis ZIP包，把全部文件解壓到redis文件夾中。（其餘盤符也能夠滴^_^）

   文件介紹：

   redis-benchmark.exe         #基準測試

   redis-check-aof.exe         # aof

   redischeck-dump.exe        # dump

   redis-cli.exe               # 客戶端

   redis-server.exe            # 服務器

   redis.windows.conf          # 配置文件

2. windows 運行（快捷鍵：windows鍵+R鍵），輸入【cmd】命令，進入DOC操做系統窗口。

   使用命令【redis-server.exe  redis.windows.conf】，啓動redis 服務【若是您沒出現以下的錯誤，直接跳過】。若是您也像我同樣出現以下的錯誤，不用急，總有解決辦法滴！

   解決辦法：

   根據提示，是 maxheap 標識有問題,打開配置文件 redis.windows.conf ,搜索 maxheap , 而後直接指定好內容便可.

   ......

   # 

   # maxheap <bytes>

   maxheap 1024000000

   .......

   而後再次啓動,OK,成功.

3. 服務啓動成功狀態

4. 啓動redis服務的doc窗口，不用關閉，由於服務須要一直執行，關閉服務，直接關閉窗口就行。

   新打開一個doc窗口，用自帶的客戶端工具進行測試 命令【redis-cli.exe】,詳細操做以下。。事例展現了一個基本的讀寫操做，設置set key->age，value->21，get age 獲得key的值。^_^

（二）、文件信息說明

    這時候，就已經完成配置了，如今說下它的的redis.conf配置文件。下面是相關項的說明：

    # Redis configuration file example  
 
    # 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.  
 
   
 
    # By default Redis does not run as a daemon. Use 'yes' if you need it.  
 
    # Note that Redis will write a pid file in /var/run/redis.pid when daemonized.  
 
    daemonize no    
 
    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  
 
   
 
    # When running daemonized, Redis writes a pid file in /var/run/redis.pid by  
 
    # default. You can specify a custom pid file location here.  
 
    pidfile /var/run/redis.pid  
 
    當Redis以守護進程方式運行時，Redis默認會把pid寫入/var/run/redis.pid文件，能夠經過pidfile指定  
 
    # Accept connections on the specified port, default is 6379.  
 
    # If port 0 is specified Redis will not listen on a TCP socket.  
     
    port 6379  
 
    指定Redis監聽端口，默認端口爲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.  
 
    #  
 
    # bind 127.0.0.1  
 
    綁定的主機地址  
 
    # 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  
 
   
 
    # Close the connection after a client is idle for N seconds (0 to disable)  
 
    timeout 0  
 
    當 客戶端閒置多長時間後關閉鏈接，若是指定爲0，表示關閉該功能  
 
    # 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)  
 
    loglevel verbose  
 
    指定日誌記錄級別，Redis總共支持四個級別：debug、verbose、notice、warning，默認爲verbose  
 
    # 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  
 
    logfile stdout  
 
    日誌記錄方式，默認爲標準輸出，若是配置Redis爲守護進程方式運行，而這裏又配置爲日誌記錄方式爲   標準輸出，則日誌將會發送給/dev/null  
 
    # To enable logging to the system logger, just set 'syslog-enabled' to yes,  
 
    # and optionally update the other syslog parameters to suit your needs.  
 
    # syslog-enabled no  
 
   
 
    # Specify the syslog identity.  
 
    # syslog-ident redis  
 
   
 
    # Specify the syslog facility.  Must be USER or between LOCAL0-LOCAL7.  
 
    # syslog-facility local0  
 
   
 
    # Set the number of databases. The default database is DB 0, you can select  
 
    # a different one on a per-connection basis using SELECT <dbid> where  
 
    # dbid is a number between 0 and 'databases'-1  
 
    databases 16  
 
    設置數據庫的數量，默認數據庫爲0，可使用SELECT <dbid>命令在鏈接上指定數據庫id  
 
    ################################ SNAPSHOTTING      #################################  
 
    #  
 
    # Save the DB on disk:  
 
    #  
 
    #   save <seconds> <changes>  
 
    #  
 
    #   Will save the DB if both the given number of seconds and the given  
 
    #   number of write operations against the DB occurred.  
 
    #  
 
    #   In the example below the behaviour will be to save:  
 
    #   after 900 sec (15 min) if at least 1 key changed  
 
    #   after 300 sec (5 min) if at least 10 keys changed  
 
    #   after 60 sec if at least 10000 keys changed  
 
    #  
 
    #   Note: you can disable saving at all commenting all the "save" lines.  
 
   
 
    save 900 1  
 
    save 300 10  
 
    save 60 10000  
 
    分別表示900秒（15分鐘）內有1個更改，300秒（5分鐘）內有10個更改以及60秒內有10000個更改。  

    指定在多長時間內，有多少次更新操做，就將數據同步到數據文件，能夠多個條件配合  
 
    # Compress string objects using LZF when dump .rdb databases?  
 
    # For default that's set to 'yes' as it's almost always a win.  
 
    # If you want to save some CPU in the saving child set it to 'no' but  
 
    # the dataset will likely be bigger if you have compressible values or keys.  
 
    rdbcompression yes  
 
    指定存儲至本地數據庫時是否壓縮數據，默認爲yes，Redis採用LZF壓縮，若是爲了節省CPU時間，能夠關閉該選項，但會致使數據庫文件變的巨大  
 
    # The filename where to dump the DB  
 
    dbfilename dump.rdb  
 
    指定本地數據庫文件名，默認值爲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.  
 
    dir ./  
 
    指定本地數據庫存放目錄  
 
    ################################# REPLICATION     #################################  
 
   
 
    # 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.  
 
    #  
 
    # slaveof <masterip> <masterport>  
 
    slaveof <masterip> <masterport> 設置當本機爲slav服務時，設置master服務的IP地址及端口，在Redis啓動時，它會自動從master進行數據同步  
 
    # If the master is password protected (using the "requirepass" configuration  
 
    # directive below) it is possible to tell the slave to authenticate before  
 
    # starting the replication synchronization process, otherwise the master will  
 
    # refuse the slave request.  
 
    #  
 
    # masterauth <master-password>  
 
    masterauth <master-password> 當master服務設置了密碼保護時，slav服務鏈接master的密碼  
 
    # 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     ###################################  
 
   
 
    # Require clients to issue AUTH <PASSWORD> before processing any other  
 
    # commands.  This might be useful in environments in which you do not trust  
 
    # others with access to the host running redis-server.  
 
    #  
 
    # This should stay commented out for backward compatibility and because most  
 
    # people do not need auth (e.g. they run their own servers).  
 
    #   
 
    # Warning: since Redis is pretty fast an outside user can try up to  
 
    # 150k passwords per second against a good box. This means that you should  
 
    # use a very strong password otherwise it will be very easy to break.  
 
    #  
 
    # requirepass foobared  
 
    requirepass foobared 設置Redis鏈接密碼，若是配置了鏈接密碼，客戶端在鏈接Redis時須要經過AUTH <password>命令提供密碼，默認關閉  
 
    # 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     ####################################  
 
   
 
    # 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'.  
 
    #  
 
    # maxclients 128  
 
    maxclients 128 設置同一時間最大客戶端鏈接數，默認無限制，Redis能夠同時打開的客戶端鏈接數爲Redis進程能夠打開的最大文件描述符數，若是設置 maxclients 0，表示不做限制。當客戶端鏈接數到達限制時，Redis會關閉新的鏈接並向客戶端返回max number of clients reached錯誤信息  
 
    # 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.  
 
    #  
 
    # maxmemory <bytes>  
 
     maxmemory <bytes>指定Redis最大內存限制，Redis在啓動時會把數據加載到內存中，達到最大內存後，Redis會先嚐試清除已到期或即將到期的Key，當此方法處理 後，仍然到達最大內存設置，將沒法再進行寫入操做，但仍然能夠進行讀取操做。Redis新的vm機制，會把Key存放內存，Value會存放在swap區  
 
    # 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     ###############################  
 
   
 
    # 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.  
 
   
 
    appendonly no  
 
    appendonly no指定是否在每次更新操做後進行日誌記錄，Redis在默認狀況下是異步的把數據寫入磁盤，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。默認爲no  
 
    # The name of the append only file (default: "appendonly.aof")  
 
    # appendfilename appendonly.aof  
 
     appendfilename appendonly.aof指定更新日誌文件名，默認爲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".  
 
   
 
    # appendfsync always  
 
    appendfsync everysec  
 
    # appendfsync no  
 
    指定更新日誌條件，共有3個可選值：  
 
    no：表示等操做系統進行數據緩存同步到磁盤（快）  
 
    always：表示每次更新操做後手動調用fsync()將數據寫到磁盤（慢，安全）  
 
    everysec：表示每秒同步一次（折衷，默認值）  
 
    # 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 100  
 
    auto-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.  
 
    #  
 
    # To enable VM just set 'vm-enabled' to yes, and set the following three  
 
    # VM parameters accordingly to your needs.  
 
   
 
    vm-enabled no  
 
    指定是否啓用虛擬內存機制，默認值爲no，簡單的介紹一下，VM機制將數據分頁存放，由Redis將訪問量較少的頁即冷數據swap到磁盤上，訪問多的頁面由磁盤自動換出到內存中（在後面的文章我會仔細分析Redis的VM機制）  
 
    # 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.  
 
    vm-swap-file /tmp/redis.swap  
 
    虛擬內存文件路徑，默認值爲/tmp/redis.swap，不可多個Redis實例共享  
 
    # 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.  
 
    vm-max-memory 0  
 
    將全部大於vm-max-memory的數據存入虛擬內存,不管vm-max-memory設置多小,全部索引數據都是內存存儲的(Redis的索引數據 就是keys),也就是說,當vm-max-memory設置爲0的時候,實際上是全部value都存在於磁盤。默認值爲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 :)  
 
    vm-page-size 32  
 
    Redis swap文件分紅了不少的page，一個對象能夠保存在多個page上面，但一個page上不能被多個對象共享，vm-page-size是要根據存儲的 數據大小來設定的，做者建議若是存儲不少小對象，page大小最好設置爲32或者64bytes；若是存儲很大大對象，則可使用更大的page，若是不 肯定，就使用默認值  
 
    # 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.  
 
    vm-pages 134217728  
 
    設置swap文件中的page數量，因爲頁表（一種表示頁面空閒或使用的bitmap）是在放在內存中的，，在磁盤上每8個pages將消耗1byte的內存。  
 
    # 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.  
 
    vm-max-threads 4  
 
    設置訪問swap文件的線程數,最好不要超過機器的核數,若是設置爲0,那麼全部對swap文件的操做都是串行的，可能會形成比較長時間的延遲。默認值爲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.  
 
    hash-max-zipmap-entries 512  
 
    hash-max-zipmap-value 64  
 
    指定在超過必定的數量或者最大的元素超過某一臨界值時，採用一種特殊的哈希算法         # 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 512         list-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 128         zset-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.         #         # use "activerehashing yes" if you don't have such hard requirements but         # want to free memory asap when possible.         activerehashing yes               ################################## INCLUDES     ###################################               # Include one or more other config files here.  This is useful if you         # have a standard template that goes to all redis server but also need         # to customize a few per-server settings.  Include files can include         # other files, so use this wisely.         #         # include /path/to/local.conf         # include /path/to/other.conf