memcached演练(1) 搭建memcached服务

iyut

memcached已经火了好多年了，现在网上关于memcached的资源相当多了，我就不浪费话语了。干脆写一个实战系列，坚持一切用实施说话。
环境介绍
Linux虚拟机
内核信息

[iyunv@hadoop1 ~]# uname -a
Linux hadoop1 2.6.32-358.el6.i686
内存：1G
安装过程
1.准备编译环境，安装必须的gcc，make工具，如果没有安装yum，最好安装下。网上有很多共享的yum源。
2.下载最新版本的libevent

1	# wget https://github.com/libevent/libe ... .0.22-stable.tar.gz

3.解压libevent对应压缩包

1	# tar zxvf libevent-2.0.22-stable.tar.gz

解压之后的文件路径：/u01/software/libevent-2.0.22-stable
3.编译libevent

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$ cd /u01/software/libevent-2.0.22-stable $  ./configure -prefix=/usr/local/libevent $ make $ make install 确认安装结果 $ ls -al /usr/local/lib |grep libevent

4.下载最新版本的memcached

1	$ wget http://memcached.org/latest

5.解压memcached对应压缩包

1	$ tar zxvf memcached-1.4.29.tar.gz

解压之后的文件路径：/u01/software/memcached-1.4.29
6.编译memcached

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$ cd /u01/software/memcached-1.4.29 $ [iyunv@hadoop1 memcached-1.4.29]# ./configure  -help `configure' configures memcached 1.4.29 to adapt to many kinds of systems. Usage: ./configure [OPTION]... [VAR=VALUE]... Configuration:   -h, --help              display this help and exit       --help=short        display options specific to this package       --help=recursive    display the short help of all the included packages   -V, --version           display version information and exit   -q, --quiet, --silent   do not print `checking ...' messages       --cache-file=FILE   cache test results in FILE [disabled]   -C, --config-cache      alias for `--cache-file=config.cache'   -n, --no-create         do not create output files       --srcdir=DIR        find the sources in DIR [configure dir or `..'] Installation directories:   --prefix=PREFIX         install architecture-independent files in PREFIX                           [/usr/local] ... Fine tuning of the installation directories:   --bindir=DIR            user executables [EPREFIX/bin]   --sbindir=DIR           system admin executables [EPREFIX/sbin]   --libexecdir=DIR        program executables [EPREFIX/libexec]   --sysconfdir=DIR        read-only single-machine data [PREFIX/etc]   --sharedstatedir=DIR    modifiable architecture-independent data [PREFIX/com]   --localstatedir=DIR     modifiable single-machine data [PREFIX/var]   --libdir=DIR            object code libraries [EPREFIX/lib]   --includedir=DIR        C header files [PREFIX/include]   --oldincludedir=DIR     C header files for non-gcc [/usr/include]   --datarootdir=DIR       read-only arch.-independent data root [PREFIX/share]   --datadir=DIR           read-only architecture-independent data [DATAROOTDIR]   --infodir=DIR           info documentation [DATAROOTDIR/info]   --localedir=DIR         locale-dependent data [DATAROOTDIR/locale]   --mandir=DIR            man documentation [DATAROOTDIR/man]   --docdir=DIR            documentation root [DATAROOTDIR/doc/memcached]   --htmldir=DIR           html documentation [DOCDIR]   --dvidir=DIR            dvi documentation [DOCDIR]   --pdfdir=DIR            pdf documentation [DOCDIR]   --psdir=DIR             ps documentation [DOCDIR]   Optional Packages:   --with-PACKAGE[=ARG]    use PACKAGE [ARG=yes]   --without-PACKAGE       do not use PACKAGE (same as --with-PACKAGE=no)   --with-libevent=PATH     Specify path to libevent installation    # ./configure --prefix=/usr/local/memcached  --with-libevent=/usr/local/lib/   # make     # make install

这时候memcached安装成功了
启动memcached

1	$ /usr/local/memcached/bin/memcached 报错

error while loading shared libraries: libevent-2.0.so.5: cannot open shared object file: No such file or directory
解决思路
##跟踪运行memcached所有加载库文件的路径

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$ LD_DEBUG=libs LD_DEBUG=libs ./memcached -v      15862:     find library=libevent-2.0.so.5 [0]; searching      15862:      search cache=/etc/ld.so.cache      15862:      search path=/lib/tls/i686/sse2:/lib/tls/i686:/lib/tls/sse2:/lib/tls:/lib/i686/sse2:/lib/i686:/lib/sse2:/lib:/usr/lib/tls/i686/sse2:/usr/lib/tls/i686:/usr/lib/tls/sse2:/usr/lib/tls:/usr/lib/i686/sse2:/usr/lib/i686:/usr/lib/sse2:/usr/lib            (system search path)      15862:       trying file=/lib/tls/i686/sse2/libevent-2.0.so.5      15862:       trying file=/lib/tls/i686/libevent-2.0.so.5      15862:       trying file=/lib/tls/sse2/libevent-2.0.so.5      15862:       trying file=/lib/tls/libevent-2.0.so.5      15862:       trying file=/lib/i686/sse2/libevent-2.0.so.5      15862:       trying file=/lib/i686/libevent-2.0.so.5      15862:       trying file=/lib/sse2/libevent-2.0.so.5      15862:       trying file=/lib/libevent-2.0.so.5      ...

首先确认建立软连接

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$ ls /usr/local/lib/libevent-2.0.so.5 /usr/local/lib/libevent-2.0.so.5 $ ln -s /usr/local/lib/libevent-2.0.so.5   /usr/lib/i686/libevent-2.0.so.5

如果以root用户登陆，必须指定-u参数

1	$ /usr/local/memcached/bin/memcached  -u hadoop

确认memcached是否启动成功

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$ ps -ef |grep memcached hadoop   15891  4034  0 22:45 pts/4    00:00:00 /usr/local/memcached/bin/memcached -u hadoop root     15899 15561  0 22:45 pts/5    00:00:00 grep memcached # netstat -tlnp |grep memcached tcp        0      0 0.0.0.0:11211               0.0.0.0:*                   LISTEN      15891/memcached      tcp        0      0 :::11211                    :::*                        LISTEN      15891/memcached

最后telnet 确认下

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$ telnet 127.0.0.1 11211 Trying 127.0.0.1... Connected to 127.0.0.1. Escape character is '^]'. stats STAT pid 15891 STAT uptime 86 STAT time 1470494793

OK。至此memcached1.4.9版本已经成功在机器上安装。个人感觉最麻烦的地方，就是处理libevent。
参考了很多资源，才把问题解决。
memcached设置自启动
为了方便，现将memcached执行变更下权限

• 最简单的启动方式
  只需在/etc/rc.d/rc.local中加入一行
  /usr/local/memcached/bin/memcached -d -m 20 -p 11211 -u hadoop
  
  

注意

-d：设置为后台进程

-u：指向用户
-p:端口
-m:内存

• 推荐的方式
  
  

2.1.拷贝memcached源码包的memcached.sysv拷贝到/etc/init.d，做为memcached的启动脚本

1	$ cp /u01/software/memcached-1.4.29/scripts/memcached.sysv  /etc/init.d/memcached

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[iyunv@hadoop1 bin]# vi /etc/init.d/memcached #! /bin/sh # # chkconfig: - 55 45 # description:  The memcached daemon is a network memory cache service. # processname: memcached # config: /etc/sysconfig/memcached # Source function library. . /etc/rc.d/init.d/functions PORT=11211 USER=nobody MAXCONN=1024 CACHESIZE=64 OPTIONS="" if [ -f /etc/sysconfig/memcached ];then     . /etc/sysconfig/memcached fi # Check that networking is up. if [ "$NETWORKING" = "no" ] then     exit 0 fi RETVAL=0 prog="memcached" start () {     echo -n $"Starting $prog: "     # insure that /var/run/memcached has proper permissions     chown $USER /var/run/memcached     daemon memcached -d -p $PORT -u $USER  -m $CACHESIZE -c $MAXCONN -P /var/run/memcached/memcached.pid $OPTIONS     RETVAL=$?     echo     [ $RETVAL -eq 0 ] && touch /var/lock/subsys/memcached } stop () {     echo -n $"Stopping $prog: "     killproc memcached     RETVAL=$?     echo     if [ $RETVAL -eq 0 ] ; then         rm -f /var/lock/subsys/memcached         rm -f /var/run/memcached/memcached.pid     fi } restart () {     stop     start } # See how we were called. case "$1" in     start)         start         ;;     stop)     stop     ;;     status)     status memcached     ;;     restart|reload)     restart     ;;     condrestart)     [ -f /var/lock/subsys/memcached ] && restart || :     ;;     *)     echo $"Usage: $0 {start|stop|status|restart|reload|condrestart}"     exit 1 esac exit $?

修改下面这一句（其实就将memcached 命令指向咱们的全路径）

daemon memcached -d -p $PORT -u $USER  -m $CACHESIZE -c $MAXCONN -P /var/run/memcached/memcached.pid $OPTIONS

daemon  /usr/local/memcached/bin/memcached  -d -p $PORT -u $USER  -m $CACHESIZE -c $MAXCONN -P /var/run/memcached/memcached.pid $OPTIONS

配置自启动

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[iyunv@hadoop1 bin]$ chkconfig memcached on [iyunv@hadoop1 bin]$ chkconfig |grep memcached memcached       0:off   1:off   2:on    3:on    4:on    5:on    6:off

安装nc

1	[iyunv@hadoop1 yum.repos.d]$ yum install nc

memcached 自带的stats命令，对搜索不太友好。为了很好的搜索，借助nc工具。
比如，想查找connection相关的参数

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[iyunv@hadoop1 yum.repos.d]# echo stats | nc 127.0.0.1 11211 |grep connection STAT curr_connections 10 STAT total_connections 13 STAT connection_structures 11

配合nc使用形式，个人参考网上资源，简单罗列下

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watch "echo stats | nc 127.0.0.1 11211" printf "stats\r\n" | nc 127.0.0.1 11211 echo stats | nc 127.0.0.1 11211

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The End
接下来，演练的内容是通过telnet命令行和JAVA 客户端工具，访问memcachd.