Linux下的Memcache安装

由于memcached安装时，需要使用libevent类库，所以先安装libevent

libevent下载网址:http://www.monkey.org/~provos/libevent/

本手册中下载的是 libevent-1.4.8-stable.tar.gz版本安装步骤如下:

1. 解压缩

tar xzfv libevent-1.4.8-stable.tar.gz

2. 进入到 libevent-1.4.8-stable目录

cd libevent-1.4.8-stable

3. 编译，安装

./configure

make

make install

注：默认安装到/usr/local/lib/ 目录

接下来，安装memcached

memcached下载网址:http://www.danga.com/memcached/download.bml

本手册中下载的是 memcached-1.2.6.tar.gz版本

安装步骤如下:

1. 解压缩

tar xzfv memcached-1.2.6.tar.gz

2. 进入到 memcached-1.2.6目录

cd memcached-1.2.6

3. 编译，安装

./configure --prefix=/local/memcached

make

make install

安装完成后，会在 /local/memcached 出现 bin和share目录

进行 bin目录，启动 memcache

方法如下:

./memcached -d -u nobody -m 512 127.0.0.1 -p 11211

此时，会报一个异常

error while loading shared libraries: libevent-1.4.so.2: cannot open shared object file: No such file or directory

原因是找不到libevent-1.4.so.2类库，解决办法如下：

使用LD_DEBUG=help ./memcached -v来确定 加载的类库路径,方法如下:

LD_DEBUG=libs ./memcached -v 2>&1 > /dev/null | less

则系统会显示:

linux:/local/memcached/bin # LD_DEBUG = libs ./memcached -v 2 >& 1 > /dev/null | less

20421 : find library = libevent- 1.4 .so .2 ; searching

20421 : search cache = /etc/ld.so.cache

20421 : 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)

20421 : trying file = /lib/tls/i686/sse2/libevent- 1.4 .so .2

20421 : trying file = /lib/tls/i686/libevent- 1.4 .so .2

20421 : trying file = /lib/tls/sse2/libevent- 1.4 .so .2

20421 : trying file = /lib/tls/libevent- 1.4 .so .2

20421 : trying file = /lib/i686/sse2/libevent- 1.4 .so .2

20421 : trying file = /lib/i686/libevent- 1.4 .so .2

20421 : trying file = /lib/sse2/libevent- 1.4 .so .2

20421 : trying file = /lib/libevent- 1.4 .so .2

20421 : trying file = /usr/lib/tls/i686/sse2/libevent- 1.4 .so .2

20421 : trying file = /usr/lib/tls/i686/libevent- 1.4 .so .2

20421 : trying file = /usr/lib/tls/sse2/libevent- 1.4 .so .2

20421 : trying file = /usr/lib/tls/libevent- 1.4 .so .2

20421 : trying file = /usr/lib/i686/sse2/libevent- 1.4 .so .2

20421 : trying file = /usr/lib/i686/libevent- 1.4 .so .2

20421 : trying file = /usr/lib/sse2/libevent- 1.4 .so .2

20421 : trying file = /usr/lib/libevent- 1.4 .so .2

20421 :

./memcached: error while loading shared libraries: libevent- 1.4 .so .2 : cannot open shared object file: No such file or directory

我们看到，memcached会到很多地方去找，所以根据其它求，我们只需建一个软链接，指定到我们安装的类库上即可

方法如下：

ln -s /usr/local/lib/libevent-1.4.so.2 /lib/libevent-1.4.so. 2

现在可以正常启动memcached了

./memcached -d -u nobody -m 512 127.0.0.1 -p 11211

到这里，看到memcached已经启动，说明安装成功。

如果要结束Memcache进程，执行：

# kill `cat /tmp/memcached.pid`

也可以启动多个守护进程，不过端口不能重复。

memcache启动参数说明:

-d选项是启动一个守护进程，

-m是分配给Memcache使用的内存数量，单位是MB，我这里是10MB，

-u是运行Memcache的用户，我这里是root，

-l是监听的服务器IP地址，如果有多个地址的话，我这里指定了服务器的IP地址192.168.0.200，

-p是设置Memcache监听的端口，我这里设置了12000，最好是1024以上的端口，

-c选项是最大运行的并发连接数，默认是1024，我这里设置了256，按照你服务器的负载量来设定，

-P是设置保存Memcache的pid文件，我这里是保存在 /tmp/memcached.pid