In 08, when contacted Memcached, it also sniffed at its client products, after all, manual code does not have a variety of ORM Native XML configuration convenient. Still, memcached is now an integral part of the server architecture.
RELATED Links:
Memcached notes-(i) Installation & General error & Monitoring
Memcached Notes--(ii) xmemcached&spring integration
Memcached Notes--(iii) Summary of the use of memcached
Memcached Notes--(iv) responding to high concurrent attacks
First, download
1. Libevent
Simply put, is an event triggered by the network library, memcached inseparable from it.
Shell Code wget http://cloud.github.com/downloads/libevent/libevent/libevent-2.0.17-stable.tar.gz
wget http://cloud.github.com/downloads/libevent/libevent/libevent-2.0.17-stable.tar.gz
2. Memcached
The protagonist of the day
Shell Code wget http://memcached.googlecode.com/files/memcached-1.4.13.tar.gz
wget http://memcached.googlecode.com/files/memcached-1.4.13.tar.gz
second, the installation
1. Libevent
Decompression
Shell Code tar zxvf libevent-2.0.17-stable.tar.gz
Tar zxvf libevent-2.0.17-stable.tar.gz
Compiling, installing
Shell code./configure--prefix=/usr && make && make install
It must be noted here that the specified
--prefix, it is necessary to configure memcached later.
2. Memcached
Extract
Shell Code tar zxvf memcached-1.4.13.tar.gz
Tar zxvf memcached-1.4.13.tar.gz
Compiling, installing
Shell code./configure--with-libevent=/usr/lib && make && make install
./configure--with-libevent=/usr/lib && make && make install
It must be specified here
libeventThe path, otherwise start the time to have not found the libevent so file error.
Start
Shell code memcached-d-M 512-p 11211-u root-c 256-p/var/run/memcached.pid
Memcached-d-M 512-p 11211-u root-c 256-p/var/run/memcached.pid
Parameters
Reference
-P <num> TCP port number to listen on (default:11211)
-U <num> UDP port number to listen on (default:11211, 0 are off)
-L <addr> interface to listen on (Default:inaddr_any, all addresses)
<addr> May is specified as Host:port. If you don ' t specify
A port number, the value you specified With-p or-u is
Used. Specify multiple addresses separated by comma
or by using-l multiple times
-D Run as a daemon
-U <username> assume identity of <username> (only when run as root)
-M <num> max memory to use for items in megabytes (default:64 MB)
-M return error on memory exhausted (rather than removing items)
-C <num> Max simultaneous connections (default:1024)
-V Verbose (print errors/warnings while in event loop)
-P <file> Save PID in <file>, only used with-d option
To turn off the memcached.
Shell code kill-9 ' Cat/var/run/memcached.pid '
Kill-9 ' Cat/var/run/memcached.pid '
is normal. Let's go telnet.
Shell Code telnet xxx.xxx.xxx.xxx 11211
Telnet xxx.xxx.xxx.xxx 11211
Then enter the shell code stats
Stats
Then you can see:
Reference
STAT PID 3021
STAT Uptime 3621
STAT Time 1331261509
STAT version 1.4.13
STAT libevent 2.0.17-stable
STAT Pointer_size 64
STAT Rusage_user 0.000000
STAT Rusage_system 0.000999
STAT Curr_connections 6
STAT Total_connections 7
STAT Connection_structures 7
STAT Reserved_fds 20
STAT Cmd_get 0
STAT Cmd_set 0
STAT Cmd_flush 0
STAT Cmd_touch 0
STAT Get_hits 0
STAT get_misses 0
STAT delete_misses 0
STAT Delete_hits 0
STAT incr_misses 0
STAT Incr_hits 0
STAT decr_misses 0
STAT Decr_hits 0
STAT cas_misses 0
STAT Cas_hits 0
STAT Cas_badval 0
STAT Touch_hits 0
STAT touch_misses 0
STAT Auth_cmds 0
STAT auth_errors 0
STAT Bytes_read 72
STAT Bytes_written 1038
STAT limit_maxbytes 52428800
STAT Accepting_conns 1
STAT Listen_disabled_num 0
STAT Threads 4
STAT Conn_yields 0
STAT Hash_power_level 16
STAT hash_bytes 524288
STAT hash_is_expanding 0
STAT expired_unfetched 0
STAT evicted_unfetched 0
STAT bytes 0
STAT Curr_items 0
STAT Total_items 0
STAT Evictions 0
STAT reclaimed 0
End
The above condition indicates that the memcached service is normal.
You can also try get, set, delete, replace
Reference to set foo 0 0 3 (Save command)
Bar (data)
STORED (Result)
Get foo (take command)
VALUE Foo 0 3 (data)
Bar (data)
Enter the shell code quit
Quit
Exit.
third, System services
Referring to the Nginx system service, you wrote a memcached system service script.
First Build
/etc/init.d/memcahedThis file, and then give it executable permissions:
Shell Code touch/etc/init.d/memcached chmod +x/etc/init.d/memcached
touch/etc/init.d/memcached
chmod +x/etc/init.d/memcached
The memcached script is as follows:
Shell Code #!/bin/bash # v.0.0.1 # Create by Snowolf at 2012.5.25 # memcached-this shell script takes care of starting a nd stopping memcached. # Chkconfig:-Description:memcache provides fast memory based storage. # processname:memcached memcached_path= "/usr/local/bin/memcached" memcached_pid= "/var/run/memcached.pid" memcached _memory= "1024" # Source function library. . /etc/rc.d/init.d/functions [-X $memcached _path] | | Exit 0 retval=0 prog= "memcached" # Start daemons. Start () {if [e $memcached _pid-a!-Z $memcached _pid];then echo $prog "already running ..." Exit 1 fi echo-n $ "starti ng $prog "# Single instance to all caches $memcached _path-m $memcached _memory-l 0.0.0.0-p 11211-u root-d-P $MEMCAC Hed_pid retval=$? [$RETVAL-eq 0] && {touch/var/lock/subsys/$prog success $ "$prog"} Echo return $RETVAL} # Stop daemons. Stop () {echo-n $ "stopping $prog" killproc-d $memcached _path echo [$RETVAL = 0] && rm-f $memcached _pid/v ar/lock/subsys/$prog retval=$? Return $RETVAL} # we were called. Case "in Start" start;; stop) stop;; Status $prog retval=$?;; restart) stop start;; * echo $ "Usage: $ {Start|stop|status|restart}" Exit 1 Esac Exit $RETVAL
#!/bin/bash # v.0.0.1 # Create by Snowolf at 2012.5.25 # memcached-this shell script takes care of starting and Stopp
ing memcached.
# Chkconfig:-Description:memcache provides fast memory based storage. # processname:memcached memcached_path= "/usr/local/bin/memcached" memcached_pid= "/var/run/memcached.pid" memcached
_memory= "1024" # Source function library. . /etc/rc.d/init.d/functions [-X $memcached _path] | |
Exit 0 retval=0 prog= "memcached" # Start daemons.
Start () {if [e $memcached _pid-a!-Z $memcached _pid];then echo $prog "already running ..." Exit 1 Fi echo-n $ "Starting $prog" # Single instance to all caches $memcached _path-m $memcached _memory-l 0
.0.0.0-p 11211-u root-d-P $memcached _pid retval=$? [$RETVAL-eq 0] && {touch/var/lock/subsys/$prog success $ "$prog"} Echo return $RE
Tval} # Stop daemons. Stop () {echo-n $ "stopping $prog" killproc-d 10$memcached _path echo [$RETVAL = 0] && rm-f $memcached _pid/var/lock/subsys/$prog retval=$?
Return $RETVAL} # we were called.
Case "in Start" start;;
stop) stop;;
Status $prog retval=$?
;;
restart) stop start;;
* echo $ "Usage: $ {Start|stop|status|restart}" Exit 1 Esac Exit $RETVAL
Note These lines of configuration, configure the memcached execution file path according to the actual situation, and memcached use memory size:
Reference memcached_path= "/usr/local/bin/memcached"
memcached_memory= "1024"
Append to System services:
Shell Code chkconfig--add memcached chkconfig memcached on
Chkconfig--add memcached
chkconfig memcached on
And then you can go through
Service memcached Start|stop|status|restartControl the memcached.
Iv. General Errors
At the beginning without specifying the libevent path to install memcached, start memcached to report this error:
Reference memcached:error while loading shared libraries:libevent-2.0.so.5:cannot open Shared object file:no such file or dir Ectory
In fact, this file is
/usr/libUnder Wrong is wrong in Linux is the 64bit system, if not specified libevent path, memcached will go
/usr/lib64Get down there.
Find this file
Shell Code Whereis libevent-2.0.so.5
Whereis libevent-2.0.so.5
Reference libevent-2.0.so:/usr/lib/libevent-2.0.so.5
Shell Code
