CentOS安装卸载memcache及JAVA示例

原文地址：http://www.cnblogs.com/zhongshengzhen/

先安装libevent,memcached依赖[b]libevent的lib[/b]
[root@VM_64_81_centos download]# wget http://www.monkey.org/~provos/libevent-1.2.tar.gz
[root@VM_64_81_centos download]# tar zxvf libevent-1.2.tar.gz
[root@VM_64_81_centos download]# cd libevent-1.2

设置安装目录
[root@VM_64_81_centos libevent-1.2]# ./configure --prefix=/usr/

安装
[root@VM_64_81_centos libevent-1.2]# make && make install

测试是否安装成功
[root@VM_64_81_centos memcached-1.2.0]# ls -al /usr/lib | grep libevent

lrwxrwxrwx 1 root root 21 Jan 14 17:47 libevent-1.2.so.1 -> libevent-1.2.so.1.0.3

-rwxr-xr-x 1 root root 264056 Jan 14 17:47 libevent-1.2.so.1.0.3

-rw-r--r-- 1 root root 430396 Jan 14 17:47 libevent.a

-rwxr-xr-x 1 root root 814 Jan 14 17:47 libevent.la

lrwxrwxrwx 1 root root 21 Jan 14 17:47 libevent.so -> libevent-1.2.so.1.0.3

安装memcache
Memcache是一个hash表形式的缓存服务。用户缓存数据达到提供响应效率和处理高并发的情况。
[root@VM_64_81_centos download]# wget http://www.danga.com/memcached/dist/memcached-1.2.0.tar.gz
[root@VM_64_81_centos download]# tar zxvf memcached-1.2.0.tar.gz
[root@VM_64_81_centos download]#cd memcached-1.2.0
[root@VM_64_81_centos memcached-1.2.0]# ./configure -with-libevent=/usr
[root@VM_64_81_centos memcached-1.2.0]# make
[root@VM_64_81_centos memcached-1.2.0]# make install

测试是否安装成功
[root@VM_64_81_centos memcached-1.2.0]# ls -al /usr/local/bin/mem*

-rwxr-xr-x 1 root root 113188 Jan 14 17:51 /usr/local/bin/memcached

-rwxr-xr-x 1 root root 117535 Jan 14 17:51 /usr/local/bin/memcached-debug

启动memcached
[root@a ~]# /usr/local/bin/memcached -d -m 512 -u root -l 127.0.0.1 -p 11211 -c 256 -P /tmp/memcached.pid
root 用户名
512缓存大小512M
192.168.137.33 本机ip
11211分配的端口
256是连接数

SPRINGMVC配置memcached
#######################设置Memcached服务器参数#######################

#设置服务器地址

memcached.server=目标服务器ip:11211 #该端口号默认为11211

#容错

memcached.failOver=true

#设置初始连接数

memcached.initConn=20

#设置最小连接数

memcached.minConn=10

#设置最大连接数

memcached.maxConn=250

#设置连接池维护线程的睡眠时间

memcached.maintSleep=3000

#设置是否使用Nagle算法（Socket的参数），如果是true在写数据时不缓冲，立即发送出去

memcached.nagle=false

#设置socket的读取等待超时时间

memcached.socketTO=3000

#设置连接心跳监测开关

memcached.aliveCheck=true

卸载memcached
1.结束memcached进程

# killall memcached

2.删除memcached目录及文件

# rm -rf /usr/local/memcached

# rm -f /etc/rc.d/init.d/memcached

3.关闭memcached开机启动

# chkconfig memcached off

4.把memcached移出开机启动

# chkconfig --del memcached

错误说明：
1、[root@VM_64_81_centos memcached-1.2.0]# /usr/local/bin/memcached -d -m 512 -u root -l 127.0.0.1 -p 11211 -c 256 -P /tmp/memcached.pid

/usr/local/bin/memcached: error while loading shared libraries: libevent-1.2.so.1: cannot open shared object file: No such file or directory

解决：
原因是memcached在/usr/lib/找不到文件，因而设置一个软连接如下：
[root@VM_64_81_centos lib]# ln -s /usr/lib/libevent-1.2.so.1 /usr/lib64/

spring+java测试Memcache
spring配置：

<bean id="testCached" class="com.danga.MemCached.MemCachedClient">
<constructor-arg><value>neeaMemcachedPoolUserLogin</value></constructor-arg>
</bean>
<bean id="memcachedPooluserLogin" class="com.danga.MemCached.SockIOPool" factory-method="getInstance"
init-method="initialize" destroy-method="shutDown">
<constructor-arg><value>neeaMemcachedPoolUserLogin</value></constructor-arg>
<property name="servers">
<list>
<value>127.0.0.1:11211</value>
</list>
</property>
<property name="initConn"><value>20</value></property>
<property name="minConn"><value>10</value></property>
<property name="maxConn"><value>800</value></property>
<property name="maintSleep"><value>30</value></property>
<property name="nagle"><value>false</value></property>
<property name="socketTO"><value>3000</value></property>
</bean>

JAVA代码：

@Component
public class SysCacheHelper {
@Autowired
@Qualifier("testCached")
private MemCachedClient cache;

public boolean setSysCache(int categoryId, TSysConfig sysConfig){
return cache.set(Constants.SYS_PREFIX + categoryId, sysConfig, LoginedCacheHelper.get3DayCalendarTime(Constants.SYS_CACHE_EXPIRED_DAY));
}
public TSysConfig getSysCache(int categoryId){
return (TSysConfig)cache.get(Constants.SYS_PREFIX + categoryId);
}
public boolean removeSysCache(int categoryId){
return cache.delete(Constants.SYS_PREFIX + categoryId);
}
}

可以调用方法查看memcached中的内容。

示例代码只是摘录重要片段。