memcached 1.2.6
-p <num>      TCP port number to listen on (default: 11211)
       侦听的TCP协议端口（默认：11211）
-U <num>      UDP port number to listen on (default: 0, off)
       侦听的UDP协议端口 （默认：关闭）
-s <file>     unix socket path to listen on (disables network support)
-a <mask>     access mask for unix socket, in octal (default 0700)
-l <ip_addr>  interface to listen on, default is INDRR_ANY
       侦听的网络端口IP
-d            run as a daemon
       后台运行
-r            maximize core file limit
       最大核心文件数
-u <username> assume identity of <username> (only when run as root)
       使用者用户名
-m <num>      max memory to use for items in megabytes, default is 64 MB
       项目最大使用内存（MB为单位）
-M            return error on memory exhausted (rather than removing items)
-c <num>      max simultaneous connections, default is 1024
       最大同时连接数
-k            lock down all paged memory.  Note that there is a
              limit on how much memory you may lock.  Trying to
              allocate more than that would fail, so be sure you
              set the limit correctly for the user you started
              the daemon with (not for -u <username> user;
              under sh this is done with 'ulimit -S -l NUM_KB').
-v            verbose (print errors/warnings while in event loop)
-vv           very verbose (also print client commands/reponses)
-h            print this help and exit
-i            print memcached and libevent license
-b            run a managed instanced (mnemonic: buckets)
-P <file>     save PID in <file>, only used with -d option
-f <factor>   chunk size growth factor, default 1.25
-n <bytes>    minimum space allocated for key+value+flags, default 48
-t <num>      number of threads to use, default 4