（一）redis源码阅读

目录

• 1. srand()和rand()函数以及随机数种子
• 2. 守护进程及pid文件
• 3. 初始化服务器时的信号处理
• 4. 在程序coredump时记录堆栈信息StackTrace
• 5. 线程主循环
• 6. 时间戳
• 7. 全局时间缓存
• 8. run_with_period 宏
• 9. /proc/getpid()/stat
• 10. Redis Command Table

1. srand()和rand()函数以及随机数种子

srand(time(NULL)^getpid());

struct timeval tv;
gettimeofday(&tv,NULL);
dictSetHashFunctionSeed(tv.tv_sec^tv.tv_usec^getpid());

2. 守护进程及pid文件

在main()函数中，通过配置文件判断是否以守护进程模式运行。

if (server.daemonize) daemonize();     // 守护进程
if (server.daemonize) createPidFile();  // 记录pid的文件

// 将程序以守护进程方式运行
void daemonize(void) {
    int fd;

    if (fork() != 0) exit(0); /* parent exits */
    setsid(); /* create a new session */

    /* Every output goes to /dev/null. If Redis is daemonized but
     * the 'logfile' is set to 'stdout' in the configuration file
     * it will not log at all. */
    if ((fd = open("/dev/null", O_RDWR, 0)) != -1) {
        dup2(fd, STDIN_FILENO);
        dup2(fd, STDOUT_FILENO);
        dup2(fd, STDERR_FILENO);
        if (fd > STDERR_FILENO) close(fd);
    }
}

// 保存进程ID到文件
void createPidFile(void) {
    /* Try to write the pid file in a best-effort way. */
    FILE *fp = fopen(server.pidfile,"w");
    if (fp) {
        fprintf(fp,"%d
",(int)getpid());
        fclose(fp);
    }
}

3. 初始化服务器时的信号处理

// 初始化服务器函数
void initServer(void) {

    // 忽视信号: SIGHUP, SIGPIPE 
    signal(SIGHUP, SIG_IGN);
    signal(SIGPIPE, SIG_IGN);

    // 设置SIGTERM, SIGINT 信号处理函数
    setupSignalHandlers();

// 设置信号处理函数，当SIGTERN, SIGINT时，退出程序
void setupSignalHandlers(void) {
    struct sigaction act;

    /* When the SA_SIGINFO flag is set in sa_flags then sa_sigaction is used.
     * Otherwise, sa_handler is used. */
    sigemptyset(&act.sa_mask);
    act.sa_flags = 0;
    act.sa_handler = sigShutdownHandler;
    sigaction(SIGTERM, &act, NULL);
    sigaction(SIGINT, &act, NULL);

#ifdef HAVE_BACKTRACE
    sigemptyset(&act.sa_mask);
    act.sa_flags = SA_NODEFER | SA_RESETHAND | SA_SIGINFO;
    act.sa_sigaction = sigsegvHandler;
    sigaction(SIGSEGV, &act, NULL);
    sigaction(SIGBUS, &act, NULL);
    sigaction(SIGFPE, &act, NULL);
    sigaction(SIGILL, &act, NULL);
#endif
    return;
}

// 信号处理函数，ctrl+c 会产生 SIGINT信号，连续两次，会退出程序。
static void sigShutdownHandler(int sig) {
    char *msg;

    switch (sig) {
    case SIGINT:
        msg = "Received SIGINT scheduling shutdown...";
        break;
    case SIGTERM:
        msg = "Received SIGTERM scheduling shutdown...";
        break;
    default:
        msg = "Received shutdown signal, scheduling shutdown...";
    };

    /* SIGINT is often delivered via Ctrl+C in an interactive session.
     * If we receive the signal the second time, we interpret this as
     * the user really wanting to quit ASAP without waiting to persist
     * on disk. */
    if (server.shutdown_asap && sig == SIGINT) {
        redisLogFromHandler(REDIS_WARNING, "You insist... exiting now.");
        rdbRemoveTempFile(getpid());
        exit(1); /* Exit with an error since this was not a clean shutdown. */
    } else if (server.loading) {
        exit(0);
    }

    redisLogFromHandler(REDIS_WARNING, msg);

	// 在接收到SIGTERM/SIGINT信号后，在信号处理函数中将server.shutdown_asap置为1；
	// 当下次运行serverCron函数时，会检查该值，然后安全退出程序。
    server.shutdown_asap = 1;
}

4. 在程序coredump时记录堆栈信息StackTrace

/* Logs the stack trace using the backtrace() call. This function is designed
 * to be called from signal handlers safely. */
void logStackTrace(ucontext_t *uc) {
    void *trace[100];
    int trace_size = 0, fd;
    int log_to_stdout = server.logfile[0] == '';

    /* Open the log file in append mode. */
    fd = log_to_stdout ?
        STDOUT_FILENO :
        open(server.logfile, O_APPEND|O_CREAT|O_WRONLY, 0644);
    if (fd == -1) return;

    /* Generate the stack trace */
    trace_size = backtrace(trace, 100);

    /* overwrite sigaction with caller's address */
    if (getMcontextEip(uc) != NULL)
        trace[1] = getMcontextEip(uc);

    /* Write symbols to log file */
    backtrace_symbols_fd(trace, trace_size, fd);

    /* Cleanup */
    if (!log_to_stdout) close(fd);
}

5. 线程主循环

// 主循环
void aeMain(aeEventLoop *eventLoop) {
    eventLoop->stop = 0;
    while (!eventLoop->stop) {
        aeProcessEvents(eventLoop, AE_ALL_EVENTS);
    }
}

6. 时间戳

/* Return the UNIX time in microseconds */
long long ustime(void) {
    struct timeval tv;
    long long ust;

    gettimeofday(&tv, NULL);
    ust = ((long long)tv.tv_sec)*1000000;
    ust += tv.tv_usec;
    return ust;
}

/* Return the UNIX time in milliseconds */
long long mstime(void) {
    return ustime()/1000;
}

7. 全局时间缓存

/* We take a cached value of the unix time in the global state because with
 * virtual memory and aging there is to store the current time in objects at
 * every object access, and accuracy is not needed. To access a global var is
 * a lot faster than calling time(NULL) */
 // 创建一个全局的时间缓存，是因为，访问全局变量比调用系统调用快。
void updateCachedTime(void) {
    server.unixtime = time(NULL);
    server.mstime = mstime();
}


/*
time_t unixtime;        /* Unix time sampled every cron cycle. */
long long mstime;       /* Like 'unixtime' but with milliseconds resolution. */
*/  

8. run_with_period 宏

/* Using the following macro you can run code inside serverCron() with the
 * specified period, specified in milliseconds.
 * The actual resolution depends on server.hz. */
#define run_with_period(_ms_) if ((_ms_ <= 1000/server.hz) || !(server.cronloops%((_ms_)/(1000/server.hz))))


run_with_period(100) {
        trackInstantaneousMetric(REDIS_METRIC_COMMAND,server.stat_numcommands);
        trackInstantaneousMetric(REDIS_METRIC_NET_INPUT,
                server.stat_net_input_bytes);
        trackInstantaneousMetric(REDIS_METRIC_NET_OUTPUT,
                server.stat_net_output_bytes);
    }

9. /proc/getpid()/stat

#if defined(HAVE_PROC_STAT)
#include <unistd.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>

// /proc/%d/stat 等文件的作用:
size_t zmalloc_get_rss(void) {
    int page = sysconf(_SC_PAGESIZE);
    size_t rss;
    char buf[4096];
    char filename[256];
    int fd, count;
    char *p, *x;

    snprintf(filename,256,"/proc/%d/stat",getpid());
    if ((fd = open(filename,O_RDONLY)) == -1) return 0;
    if (read(fd,buf,4096) <= 0) {
        close(fd);
        return 0;
    }
    close(fd);

    // 分离出第24个字段
    p = buf;
    count = 23; /* RSS is the 24th field in /proc/<pid>/stat */
    while(p && count--) {
        p = strchr(p,' ');
        if (p) p++;
    }
    if (!p) return 0;
    x = strchr(p,' ');
    if (!x) return 0;
    *x = '';

    rss = strtoll(p,NULL,10);
    rss *= page;
    return rss;
}
#endif

10. Redis Command Table

如果是C++中，则可使用std::map来实现命令表

/** std::string   name;  // 命令名
  *  std::function<void(client*)>  func;  // 处理函数
*/
std::map<std::string, std::function<void(client *)>> commandMap;

/* Populates the Redis Command Table starting from the hard coded list
 * we have on top of redis.c file. */
void populateCommandTable(void) {
    int j;
    int numcommands = sizeof(redisCommandTable)/sizeof(struct redisCommand);

    for (j = 0; j < numcommands; j++) {
        struct redisCommand *c = redisCommandTable+j;
        char *f = c->sflags;
        int retval1, retval2;

        while(*f != '') {
            switch(*f) {
            case 'w': c->flags |= REDIS_CMD_WRITE; break;
            case 'r': c->flags |= REDIS_CMD_READONLY; break;
            case 'm': c->flags |= REDIS_CMD_DENYOOM; break;
            case 'a': c->flags |= REDIS_CMD_ADMIN; break;
            case 'p': c->flags |= REDIS_CMD_PUBSUB; break;
            case 's': c->flags |= REDIS_CMD_NOSCRIPT; break;
            case 'R': c->flags |= REDIS_CMD_RANDOM; break;
            case 'S': c->flags |= REDIS_CMD_SORT_FOR_SCRIPT; break;
            case 'l': c->flags |= REDIS_CMD_LOADING; break;
            case 't': c->flags |= REDIS_CMD_STALE; break;
            case 'M': c->flags |= REDIS_CMD_SKIP_MONITOR; break;
            case 'k': c->flags |= REDIS_CMD_ASKING; break;
            case 'F': c->flags |= REDIS_CMD_FAST; break;
            default: redisPanic("Unsupported command flag"); break;
            }
            f++;
        }

        retval1 = dictAdd(server.commands, sdsnew(c->name), c);
        /* Populate an additional dictionary that will be unaffected
         * by rename-command statements in redis.conf. */
        retval2 = dictAdd(server.orig_commands, sdsnew(c->name), c);
        redisAssert(retval1 == DICT_OK && retval2 == DICT_OK);
    }
}

在redis.h文件中定义有Redis Command Table：

// redisCommand 结构，记录一个redis命令的实现信息。
struct redisCommand {
    char *name;              // 命令名
    redisCommandProc *proc;  // 命令处理函数
    int arity;               // 参数数量
    char *sflags; /* Flags as string representation, one char per flag. */
    int flags;    /* The actual flags, obtained from the 'sflags' field. */
    /* Use a function to determine keys arguments in a command line.
     * Used for Redis Cluster redirect. */
    redisGetKeysProc *getkeys_proc;
    /* What keys should be loaded in background when calling this command? */
    int firstkey; /* The first argument that's a key (0 = no keys) */
    int lastkey;  /* The last argument that's a key */
    int keystep;  /* The step between first and last key */
    long long microseconds, calls;
};

/* Our command table.
 *
 * Every entry is composed of the following fields:
 *
 * name: a string representing the command name.
 * function: pointer to the C function implementing the command.
 * arity: number of arguments, it is possible to use -N to say >= N
 * sflags: command flags as string. See below for a table of flags.
 * flags: flags as bitmask. Computed by Redis using the 'sflags' field.
 * get_keys_proc: an optional function to get key arguments from a command.
 *                This is only used when the following three fields are not
 *                enough to specify what arguments are keys.
 * first_key_index: first argument that is a key
 * last_key_index: last argument that is a key
 * key_step: step to get all the keys from first to last argument. For instance
 *           in MSET the step is two since arguments are key,val,key,val,...
 * microseconds: microseconds of total execution time for this command.
 * calls: total number of calls of this command.
 *
 * The flags, microseconds and calls fields are computed by Redis and should
 * always be set to zero.
 *
 * Command flags are expressed using strings where every character represents
 * a flag. Later the populateCommandTable() function will take care of
 * populating the real 'flags' field using this characters.
 *
 * This is the meaning of the flags:
 *
 * w: write command (may modify the key space).
 * r: read command  (will never modify the key space).
 * m: may increase memory usage once called. Don't allow if out of memory.
 * a: admin command, like SAVE or SHUTDOWN.
 * p: Pub/Sub related command.
 * f: force replication of this command, regardless of server.dirty.
 * s: command not allowed in scripts.
 * R: random command. Command is not deterministic, that is, the same command
 *    with the same arguments, with the same key space, may have different
 *    results. For instance SPOP and RANDOMKEY are two random commands.
 * S: Sort command output array if called from script, so that the output
 *    is deterministic.
 * l: Allow command while loading the database.
 * t: Allow command while a slave has stale data but is not allowed to
 *    server this data. Normally no command is accepted in this condition
 *    but just a few.
 * M: Do not automatically propagate the command on MONITOR.
 * k: Perform an implicit ASKING for this command, so the command will be
 *    accepted in cluster mode if the slot is marked as 'importing'.
 * F: Fast command: O(1) or O(log(N)) command that should never delay
 *    its execution as long as the kernel scheduler is giving us time.
 *    Note that commands that may trigger a DEL as a side effect (like SET)
 *    are not fast commands.
 */
struct redisCommand redisCommandTable[] = {
    {"get",getCommand,2,"rF",0,NULL,1,1,1,0,0},
    {"set",setCommand,-3,"wm",0,NULL,1,1,1,0,0},
    {"setnx",setnxCommand,3,"wmF",0,NULL,1,1,1,0,0},
    {"setex",setexCommand,4,"wm",0,NULL,1,1,1,0,0},
    {"psetex",psetexCommand,4,"wm",0,NULL,1,1,1,0,0},
    {"append",appendCommand,3,"wm",0,NULL,1,1,1,0,0},
    {"strlen",strlenCommand,2,"rF",0,NULL,1,1,1,0,0},
    {"del",delCommand,-2,"w",0,NULL,1,-1,1,0,0},
    {"exists",existsCommand,-2,"rF",0,NULL,1,-1,1,0,0},
    {"setbit",setbitCommand,4,"wm",0,NULL,1,1,1,0,0},
    {"getbit",getbitCommand,3,"rF",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,"wmF",0,NULL,1,1,1,0,0},
    {"decr",decrCommand,2,"wmF",0,NULL,1,1,1,0,0},
    {"mget",mgetCommand,-2,"r",0,NULL,1,-1,1,0,0},
    {"rpush",rpushCommand,-3,"wmF",0,NULL,1,1,1,0,0},
    {"lpush",lpushCommand,-3,"wmF",0,NULL,1,1,1,0,0},
    {"rpushx",rpushxCommand,3,"wmF",0,NULL,1,1,1,0,0},
    {"lpushx",lpushxCommand,3,"wmF",0,NULL,1,1,1,0,0},
    {"linsert",linsertCommand,5,"wm",0,NULL,1,1,1,0,0},
    {"rpop",rpopCommand,2,"wF",0,NULL,1,1,1,0,0},
    {"lpop",lpopCommand,2,"wF",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,"rF",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,"wmF",0,NULL,1,1,1,0,0},
    {"srem",sremCommand,-3,"wF",0,NULL,1,1,1,0,0},
    {"smove",smoveCommand,4,"wF",0,NULL,1,2,1,0,0},
    {"sismember",sismemberCommand,3,"rF",0,NULL,1,1,1,0,0},
    {"scard",scardCommand,2,"rF",0,NULL,1,1,1,0,0},
    {"spop",spopCommand,2,"wRsF",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},
    {"sscan",sscanCommand,-3,"rR",0,NULL,1,1,1,0,0},
    {"zadd",zaddCommand,-4,"wmF",0,NULL,1,1,1,0,0},
    {"zincrby",zincrbyCommand,4,"wmF",0,NULL,1,1,1,0,0},
    {"zrem",zremCommand,-3,"wF",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},
    {"zremrangebylex",zremrangebylexCommand,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},
    {"zrangebylex",zrangebylexCommand,-4,"r",0,NULL,1,1,1,0,0},
    {"zrevrangebylex",zrevrangebylexCommand,-4,"r",0,NULL,1,1,1,0,0},
    {"zcount",zcountCommand,4,"rF",0,NULL,1,1,1,0,0},
    {"zlexcount",zlexcountCommand,4,"rF",0,NULL,1,1,1,0,0},
    {"zrevrange",zrevrangeCommand,-4,"r",0,NULL,1,1,1,0,0},
    {"zcard",zcardCommand,2,"rF",0,NULL,1,1,1,0,0},
    {"zscore",zscoreCommand,3,"rF",0,NULL,1,1,1,0,0},
    {"zrank",zrankCommand,3,"rF",0,NULL,1,1,1,0,0},
    {"zrevrank",zrevrankCommand,3,"rF",0,NULL,1,1,1,0,0},
    {"zscan",zscanCommand,-3,"rR",0,NULL,1,1,1,0,0},
    {"hset",hsetCommand,4,"wmF",0,NULL,1,1,1,0,0},
    {"hsetnx",hsetnxCommand,4,"wmF",0,NULL,1,1,1,0,0},
    {"hget",hgetCommand,3,"rF",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,"wmF",0,NULL,1,1,1,0,0},
    {"hincrbyfloat",hincrbyfloatCommand,4,"wmF",0,NULL,1,1,1,0,0},
    {"hdel",hdelCommand,-3,"wF",0,NULL,1,1,1,0,0},
    {"hlen",hlenCommand,2,"rF",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,"rF",0,NULL,1,1,1,0,0},
    {"hscan",hscanCommand,-3,"rR",0,NULL,1,1,1,0,0},
    {"incrby",incrbyCommand,3,"wmF",0,NULL,1,1,1,0,0},
    {"decrby",decrbyCommand,3,"wmF",0,NULL,1,1,1,0,0},
    {"incrbyfloat",incrbyfloatCommand,3,"wmF",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,"rlF",0,NULL,0,0,0,0,0},
    {"move",moveCommand,3,"wF",0,NULL,1,1,1,0,0},
    {"rename",renameCommand,3,"w",0,NULL,1,2,1,0,0},
    {"renamenx",renamenxCommand,3,"wF",0,NULL,1,2,1,0,0},
    {"expire",expireCommand,3,"wF",0,NULL,1,1,1,0,0},
    {"expireat",expireatCommand,3,"wF",0,NULL,1,1,1,0,0},
    {"pexpire",pexpireCommand,3,"wF",0,NULL,1,1,1,0,0},
    {"pexpireat",pexpireatCommand,3,"wF",0,NULL,1,1,1,0,0},
    {"keys",keysCommand,2,"rS",0,NULL,0,0,0,0,0},
    {"scan",scanCommand,-2,"rR",0,NULL,0,0,0,0,0},
    {"dbsize",dbsizeCommand,1,"rF",0,NULL,0,0,0,0,0},
    {"auth",authCommand,2,"rsltF",0,NULL,0,0,0,0,0},
    {"ping",pingCommand,-1,"rtF",0,NULL,0,0,0,0,0},
    {"echo",echoCommand,2,"rF",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,"arlt",0,NULL,0,0,0,0,0},
    {"lastsave",lastsaveCommand,1,"rRF",0,NULL,0,0,0,0,0},
    {"type",typeCommand,2,"rF",0,NULL,1,1,1,0,0},
    {"multi",multiCommand,1,"rsF",0,NULL,0,0,0,0,0},
    {"exec",execCommand,1,"sM",0,NULL,0,0,0,0,0},
    {"discard",discardCommand,1,"rsF",0,NULL,0,0,0,0,0},
    {"sync",syncCommand,1,"ars",0,NULL,0,0,0,0,0},
    {"psync",syncCommand,3,"ars",0,NULL,0,0,0,0,0},
    {"replconf",replconfCommand,-1,"arslt",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,sortGetKeys,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,"rF",0,NULL,1,1,1,0,0},
    {"pttl",pttlCommand,2,"rF",0,NULL,1,1,1,0,0},
    {"persist",persistCommand,2,"wF",0,NULL,1,1,1,0,0},
    {"slaveof",slaveofCommand,3,"ast",0,NULL,0,0,0,0,0},
    {"role",roleCommand,1,"lst",0,NULL,0,0,0,0,0},
    {"debug",debugCommand,-2,"as",0,NULL,0,0,0,0,0},
    {"config",configCommand,-2,"art",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,"pltrF",0,NULL,0,0,0,0,0},
    {"pubsub",pubsubCommand,-2,"pltrR",0,NULL,0,0,0,0,0},
    {"watch",watchCommand,-2,"rsF",0,NULL,1,-1,1,0,0},
    {"unwatch",unwatchCommand,1,"rsF",0,NULL,0,0,0,0,0},
    {"cluster",clusterCommand,-2,"ar",0,NULL,0,0,0,0,0},
    {"restore",restoreCommand,-4,"wm",0,NULL,1,1,1,0,0},
    {"restore-asking",restoreCommand,-4,"wmk",0,NULL,1,1,1,0,0},
    {"migrate",migrateCommand,-6,"w",0,migrateGetKeys,0,0,0,0,0},
    {"asking",askingCommand,1,"r",0,NULL,0,0,0,0,0},
    {"readonly",readonlyCommand,1,"rF",0,NULL,0,0,0,0,0},
    {"readwrite",readwriteCommand,1,"rF",0,NULL,0,0,0,0,0},
    {"dump",dumpCommand,2,"r",0,NULL,1,1,1,0,0},
    {"object",objectCommand,3,"r",0,NULL,2,2,2,0,0},
    {"client",clientCommand,-2,"rs",0,NULL,0,0,0,0,0},
    {"eval",evalCommand,-3,"s",0,evalGetKeys,0,0,0,0,0},
    {"evalsha",evalShaCommand,-3,"s",0,evalGetKeys,0,0,0,0,0},
    {"slowlog",slowlogCommand,-2,"r",0,NULL,0,0,0,0,0},
    {"script",scriptCommand,-2,"rs",0,NULL,0,0,0,0,0},
    {"time",timeCommand,1,"rRF",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},
    {"bitpos",bitposCommand,-3,"r",0,NULL,1,1,1,0,0},
    {"wait",waitCommand,3,"rs",0,NULL,0,0,0,0,0},
    {"command",commandCommand,0,"rlt",0,NULL,0,0,0,0,0},
    {"pfselftest",pfselftestCommand,1,"r",0,NULL,0,0,0,0,0},
    {"pfadd",pfaddCommand,-2,"wmF",0,NULL,1,1,1,0,0},
    {"pfcount",pfcountCommand,-2,"r",0,NULL,1,-1,1,0,0},
    {"pfmerge",pfmergeCommand,-2,"wm",0,NULL,1,-1,1,0,0},
    {"pfdebug",pfdebugCommand,-3,"w",0,NULL,0,0,0,0,0},
    {"latency",latencyCommand,-2,"arslt",0,NULL,0,0,0,0,0}
};