Redis启动流程分析
涉及的组件 Redis是基于C语言的,每个C文件对应一个模块,可以认为是一个组件。根据对其源代码的分析可以得出,在Redis服务启动的时候涉及到以下几个组件模块和方法。 启动时序图 在redis.c的main函数,主要做三件事情: 1)加载配置包括从命令行或者传入配
涉及的组件
Redis是基于C语言的,每个C文件对应一个模块,可以认为是一个组件。根据对其源代码的分析可以得出,在Redis服务启动的时候涉及到以下几个组件模块和方法。
启动时序图
在redis.c的main函数,主要做三件事情:
1)加载配置包括从命令行或者传入配置文件加载;
2)启动unix和tcp的监听,客户端的列表保存在redisserver的clients中;
3)启动AE事件。
启动完成,AE会定时间去查询各个客户端是否有输入,如果有读取客户端输入并且对命令进行解析。
对命令的解析主要是基于redisserver的redisCommandTable (redis.c)进行,从这个结构体可以看出REDIS所有的命令列表以及对应的处理函数。
struct redisCommand redisCommandTable[] = { {"get",getCommand,2,"r",0,NULL,1,1,1,0,0}, {"set",setCommand,-3,"wm",0,noPreloadGetKeys,1,1,1,0,0}, {"setnx",setnxCommand,3,"wm",0,noPreloadGetKeys,1,1,1,0,0}, {"setex",setexCommand,4,"wm",0,noPreloadGetKeys,1,1,1,0,0}, {"psetex",psetexCommand,4,"wm",0,noPreloadGetKeys,1,1,1,0,0}, {"append",appendCommand,3,"wm",0,NULL,1,1,1,0,0}, {"strlen",strlenCommand,2,"r",0,NULL,1,1,1,0,0}, {"del",delCommand,-2,"w",0,noPreloadGetKeys,1,-1,1,0,0}, {"exists",existsCommand,2,"r",0,NULL,1,1,1,0,0}, {"setbit",setbitCommand,4,"wm",0,NULL,1,1,1,0,0}, {"getbit",getbitCommand,3,"r",0,NULL,1,1,1,0,0}, {"setrange",setrangeCommand,4,"wm",0,NULL,1,1,1,0,0}, {"getrange",getrangeCommand,4,"r",0,NULL,1,1,1,0,0}, {"substr",getrangeCommand,4,"r",0,NULL,1,1,1,0,0}, {"incr",incrCommand,2,"wm",0,NULL,1,1,1,0,0}, {"decr",decrCommand,2,"wm",0,NULL,1,1,1,0,0}, {"mget",mgetCommand,-2,"r",0,NULL,1,-1,1,0,0}, {"rpush",rpushCommand,-3,"wm",0,NULL,1,1,1,0,0}, {"lpush",lpushCommand,-3,"wm",0,NULL,1,1,1,0,0}, {"rpushx",rpushxCommand,3,"wm",0,NULL,1,1,1,0,0}, {"lpushx",lpushxCommand,3,"wm",0,NULL,1,1,1,0,0}, {"linsert",linsertCommand,5,"wm",0,NULL,1,1,1,0,0}, {"rpop",rpopCommand,2,"w",0,NULL,1,1,1,0,0}, {"lpop",lpopCommand,2,"w",0,NULL,1,1,1,0,0}, {"brpop",brpopCommand,-3,"ws",0,NULL,1,1,1,0,0}, {"brpoplpush",brpoplpushCommand,4,"wms",0,NULL,1,2,1,0,0}, {"blpop",blpopCommand,-3,"ws",0,NULL,1,-2,1,0,0}, {"llen",llenCommand,2,"r",0,NULL,1,1,1,0,0}, {"lindex",lindexCommand,3,"r",0,NULL,1,1,1,0,0}, {"lset",lsetCommand,4,"wm",0,NULL,1,1,1,0,0}, {"lrange",lrangeCommand,4,"r",0,NULL,1,1,1,0,0}, {"ltrim",ltrimCommand,4,"w",0,NULL,1,1,1,0,0}, {"lrem",lremCommand,4,"w",0,NULL,1,1,1,0,0}, {"rpoplpush",rpoplpushCommand,3,"wm",0,NULL,1,2,1,0,0}, {"sadd",saddCommand,-3,"wm",0,NULL,1,1,1,0,0}, {"srem",sremCommand,-3,"w",0,NULL,1,1,1,0,0}, {"smove",smoveCommand,4,"w",0,NULL,1,2,1,0,0}, {"sismember",sismemberCommand,3,"r",0,NULL,1,1,1,0,0}, {"scard",scardCommand,2,"r",0,NULL,1,1,1,0,0}, {"spop",spopCommand,2,"wRs",0,NULL,1,1,1,0,0}, {"srandmember",srandmemberCommand,-2,"rR",0,NULL,1,1,1,0,0}, {"sinter",sinterCommand,-2,"rS",0,NULL,1,-1,1,0,0}, {"sinterstore",sinterstoreCommand,-3,"wm",0,NULL,1,-1,1,0,0}, {"sunion",sunionCommand,-2,"rS",0,NULL,1,-1,1,0,0}, {"sunionstore",sunionstoreCommand,-3,"wm",0,NULL,1,-1,1,0,0}, {"sdiff",sdiffCommand,-2,"rS",0,NULL,1,-1,1,0,0}, {"sdiffstore",sdiffstoreCommand,-3,"wm",0,NULL,1,-1,1,0,0}, {"smembers",sinterCommand,2,"rS",0,NULL,1,1,1,0,0}, {"zadd",zaddCommand,-4,"wm",0,NULL,1,1,1,0,0}, {"zincrby",zincrbyCommand,4,"wm",0,NULL,1,1,1,0,0}, {"zrem",zremCommand,-3,"w",0,NULL,1,1,1,0,0}, {"zremrangebyscore",zremrangebyscoreCommand,4,"w",0,NULL,1,1,1,0,0}, {"zremrangebyrank",zremrangebyrankCommand,4,"w",0,NULL,1,1,1,0,0}, {"zunionstore",zunionstoreCommand,-4,"wm",0,zunionInterGetKeys,0,0,0,0,0}, {"zinterstore",zinterstoreCommand,-4,"wm",0,zunionInterGetKeys,0,0,0,0,0}, {"zrange",zrangeCommand,-4,"r",0,NULL,1,1,1,0,0}, {"zrangebyscore",zrangebyscoreCommand,-4,"r",0,NULL,1,1,1,0,0}, {"zrevrangebyscore",zrevrangebyscoreCommand,-4,"r",0,NULL,1,1,1,0,0}, {"zcount",zcountCommand,4,"r",0,NULL,1,1,1,0,0}, {"zrevrange",zrevrangeCommand,-4,"r",0,NULL,1,1,1,0,0}, {"zcard",zcardCommand,2,"r",0,NULL,1,1,1,0,0}, {"zscore",zscoreCommand,3,"r",0,NULL,1,1,1,0,0}, {"zrank",zrankCommand,3,"r",0,NULL,1,1,1,0,0}, {"zrevrank",zrevrankCommand,3,"r",0,NULL,1,1,1,0,0}, {"hset",hsetCommand,4,"wm",0,NULL,1,1,1,0,0}, {"hsetnx",hsetnxCommand,4,"wm",0,NULL,1,1,1,0,0}, {"hget",hgetCommand,3,"r",0,NULL,1,1,1,0,0}, {"hmset",hmsetCommand,-4,"wm",0,NULL,1,1,1,0,0}, {"hmget",hmgetCommand,-3,"r",0,NULL,1,1,1,0,0}, {"hincrby",hincrbyCommand,4,"wm",0,NULL,1,1,1,0,0}, {"hincrbyfloat",hincrbyfloatCommand,4,"wm",0,NULL,1,1,1,0,0}, {"hdel",hdelCommand,-3,"w",0,NULL,1,1,1,0,0}, {"hlen",hlenCommand,2,"r",0,NULL,1,1,1,0,0}, {"hkeys",hkeysCommand,2,"rS",0,NULL,1,1,1,0,0}, {"hvals",hvalsCommand,2,"rS",0,NULL,1,1,1,0,0}, {"hgetall",hgetallCommand,2,"r",0,NULL,1,1,1,0,0}, {"hexists",hexistsCommand,3,"r",0,NULL,1,1,1,0,0}, {"incrby",incrbyCommand,3,"wm",0,NULL,1,1,1,0,0}, {"decrby",decrbyCommand,3,"wm",0,NULL,1,1,1,0,0}, {"incrbyfloat",incrbyfloatCommand,3,"wm",0,NULL,1,1,1,0,0}, {"getset",getsetCommand,3,"wm",0,NULL,1,1,1,0,0}, {"mset",msetCommand,-3,"wm",0,NULL,1,-1,2,0,0}, {"msetnx",msetnxCommand,-3,"wm",0,NULL,1,-1,2,0,0}, {"randomkey",randomkeyCommand,1,"rR",0,NULL,0,0,0,0,0}, {"select",selectCommand,2,"rl",0,NULL,0,0,0,0,0}, {"move",moveCommand,3,"w",0,NULL,1,1,1,0,0}, {"rename",renameCommand,3,"w",0,renameGetKeys,1,2,1,0,0}, {"renamenx",renamenxCommand,3,"w",0,renameGetKeys,1,2,1,0,0}, {"expire",expireCommand,3,"w",0,NULL,1,1,1,0,0}, {"expireat",expireatCommand,3,"w",0,NULL,1,1,1,0,0}, {"pexpire",pexpireCommand,3,"w",0,NULL,1,1,1,0,0}, {"pexpireat",pexpireatCommand,3,"w",0,NULL,1,1,1,0,0}, {"keys",keysCommand,2,"rS",0,NULL,0,0,0,0,0}, {"dbsize",dbsizeCommand,1,"r",0,NULL,0,0,0,0,0}, {"auth",authCommand,2,"rsl",0,NULL,0,0,0,0,0}, {"ping",pingCommand,1,"r",0,NULL,0,0,0,0,0}, {"echo",echoCommand,2,"r",0,NULL,0,0,0,0,0}, {"save",saveCommand,1,"ars",0,NULL,0,0,0,0,0}, {"bgsave",bgsaveCommand,1,"ar",0,NULL,0,0,0,0,0}, {"bgrewriteaof",bgrewriteaofCommand,1,"ar",0,NULL,0,0,0,0,0}, {"shutdown",shutdownCommand,-1,"ar",0,NULL,0,0,0,0,0}, {"lastsave",lastsaveCommand,1,"rR",0,NULL,0,0,0,0,0}, {"type",typeCommand,2,"r",0,NULL,1,1,1,0,0}, {"multi",multiCommand,1,"rs",0,NULL,0,0,0,0,0}, {"exec",execCommand,1,"sM",0,NULL,0,0,0,0,0}, {"discard",discardCommand,1,"rs",0,NULL,0,0,0,0,0}, {"sync",syncCommand,1,"ars",0,NULL,0,0,0,0,0}, {"replconf",replconfCommand,-1,"ars",0,NULL,0,0,0,0,0}, {"flushdb",flushdbCommand,1,"w",0,NULL,0,0,0,0,0}, {"flushall",flushallCommand,1,"w",0,NULL,0,0,0,0,0}, {"sort",sortCommand,-2,"wm",0,NULL,1,1,1,0,0}, {"info",infoCommand,-1,"rlt",0,NULL,0,0,0,0,0}, {"monitor",monitorCommand,1,"ars",0,NULL,0,0,0,0,0}, {"ttl",ttlCommand,2,"r",0,NULL,1,1,1,0,0}, {"pttl",pttlCommand,2,"r",0,NULL,1,1,1,0,0}, {"persist",persistCommand,2,"w",0,NULL,1,1,1,0,0}, {"slaveof",slaveofCommand,3,"ast",0,NULL,0,0,0,0,0}, {"debug",debugCommand,-2,"as",0,NULL,0,0,0,0,0}, {"config",configCommand,-2,"ar",0,NULL,0,0,0,0,0}, {"subscribe",subscribeCommand,-2,"rpslt",0,NULL,0,0,0,0,0}, {"unsubscribe",unsubscribeCommand,-1,"rpslt",0,NULL,0,0,0,0,0}, {"psubscribe",psubscribeCommand,-2,"rpslt",0,NULL,0,0,0,0,0}, {"punsubscribe",punsubscribeCommand,-1,"rpslt",0,NULL,0,0,0,0,0}, {"publish",publishCommand,3,"pfltr",0,NULL,0,0,0,0,0}, {"watch",watchCommand,-2,"rs",0,noPreloadGetKeys,1,-1,1,0,0}, {"unwatch",unwatchCommand,1,"rs",0,NULL,0,0,0,0,0}, {"restore",restoreCommand,4,"awm",0,NULL,1,1,1,0,0}, {"migrate",migrateCommand,6,"aw",0,NULL,0,0,0,0,0}, {"dump",dumpCommand,2,"ar",0,NULL,1,1,1,0,0}, {"object",objectCommand,-2,"r",0,NULL,2,2,2,0,0}, {"client",clientCommand,-2,"ar",0,NULL,0,0,0,0,0}, {"eval",evalCommand,-3,"s",0,zunionInterGetKeys,0,0,0,0,0}, {"evalsha",evalShaCommand,-3,"s",0,zunionInterGetKeys,0,0,0,0,0}, {"slowlog",slowlogCommand,-2,"r",0,NULL,0,0,0,0,0}, {"script",scriptCommand,-2,"ras",0,NULL,0,0,0,0,0}, {"time",timeCommand,1,"rR",0,NULL,0,0,0,0,0}, {"bitop",bitopCommand,-4,"wm",0,NULL,2,-1,1,0,0}, {"bitcount",bitcountCommand,-2,"r",0,NULL,1,1,1,0,0} };

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