[原创]测试memcached

 

1.安装并测试repcached

 

1.下载memcached-1.2.8-repcached-2.2.1.tar.gz

地址：http://sourceforge.net/projects/repcached/files/repcached/2.2.1-1.2.8/

 

2. 在server2，server3上分别安装repcached

 

首先安装libevent，libevent-devel:

[root@server2 Share]# rmp -ivh libevent-1.4.13-4.el6.x86_64.rpm

[root@server2 Share]# rmp -ivh libevent-devel-1.4.13-4.el6.x86_64.rpm

 

或者在CentOS下直接运行 yum libevent libevent-devel

 

安装repcached

[root@server3 bin]# ./configure --enable-replication --program-transform-name=s/memcached/repcached/

[root@server3 bin]# make

[root@server3 bin]# make install

 

3.启动repcached

切换到非root用户

[root@server3 bin]# su admin

server2 上以master身份运行，server3中以slave身份运行

 

[admin@server2 ~]$ /usr/local/bin/repcached -p 11211 -v

[admin@server2 ~]$ replication: listen

 

[admin@server3 ~]$ /usr/local/bin/repcached -p 11211 -x server2 -v

replication: connect (peer=192.168.1.202:11212)

replication: marugoto copying

replication: start

 

开启两个终端，分别连接server2，server3的11211端口

[admin@server1 ~]$ telnet server2 11211

Trying 192.168.1.202...

Connected to server2.

Escape character is '^]'.

 

[admin@server1 ~]$ telnet server3 11211

Trying 192.168.1.203...

Connected to server3.

Escape character is '^]'.

 

在server2中设置一个变量aa

set aa 0 0 5

bbbbb

STORED

get aa

VALUE aa 0 5

bbbbb

END

 

在server3中查询变量aa

get aa

VALUE aa 0 5

bbbbb

END

 

在server3中修改aa的值

append aa 0 0 3

ccc

STORED

get aa

VALUE aa 0 8

bbbbbccc

END

 

在server2中查看aa

get aa

VALUE aa 0 8

bbbbbccc

END

 

在server3中删除aa

delete aa

DELETED

get aa

END

 

在server2中查看aa

delete aa

NOT_FOUND

get aa

END

 

 

 

2. Java操作memcached

 

使用JDBC连接PostGreSQL数据库，查询一段数据并保存在memcached。分别再从memcached和PostGreSQL中查询该段数据，比较二者时间差异。

 

import com.whalin.MemCached.MemCachedClient;

import com.whalin.MemCached.SockIOPool;

import java.sql.Connection;

import java.sql.DriverManager;

import java.sql.ResultSet;

import java.sql.SQLException;

import java.sql.Statement;

import java.util.ArrayList;

import java.util.List;

 

 

public class MemChachedTest {

 

    public static void main(String[] args) throws ClassNotFoundException, SQLException {

        Class.forName("org.postgresql.Driver");

        String postGresURL = "jdbc:postgresql://10.1.20.202:5432/testdb";

        Connection con = null;

        Statement st = null;

 

        String[] memCachedServer = {"10.1.20.202:11211"};

        SockIOPool pool = null;

 

        List<String> cacheValues = new ArrayList<String>();

        try {

 

            //连接数据库

            con = DriverManager.getConnection(postGresURL, "username", "password");

            st = con.createStatement();

 

            //从数据中查询，并取出结果

            String sql = "select group.display_name from group, group_item, device "

                    + "where group_item.group_id= group.id and group_item.item_id= device.id; ";

            ResultSet rs = st.executeQuery(sql);

            while (rs.next()) {

                 cacheValues.add(rs.getString(1));

            }

            rs.close();

 

            //连接MemCached，并保存结果

            pool = SockIOPool.getInstance();

            pool.setServers(memCachedServer);

            pool.initialize();

            MemCachedClient memCachedClient = new MemCachedClient();

            memCachedClient.set("cacheValues", cacheValues);

 

 

            //再次查询数据库，并计算所耗时间

            long beforeQuery = System.currentTimeMillis();

            rs = st.executeQuery(sql);

            long afterQuery = System.currentTimeMillis();

            System.out.println("\n\n\n Cost Time of Query from PostGreSQL (ms):" + (afterQuery - beforeQuery));

 

            //查询MemCached，并计算所耗时间

            long beforeGet = System.currentTimeMillis();

            List<String> resultCached = (List<String>) memCachedClient.get("cacheValues");

            long afterGet = System.currentTimeMillis();

            System.out.println("\n\n\n Cost Time of Get from MemCached (ms):" + (afterGet - beforeGet));

 

            //打印从数据库中查询的结果

            System.out.println("\n\n-----data from PostGreSQL------");

            while (rs.next()) {

                 System.out.println(rs.getString(1));

            }

            rs.close();

 

            //打印从MemCached查询的结果

            System.out.println("\n\n-----data from MemCached------");

            for (String s :resultCached) {

                 System.out.println(s);

             }

        } finally {

            if (st != null) {

                try {

                    st.close();

                } catch (SQLException ex) {

                }

            }

            if (con != null) {

                try {

                    con.close();

                } catch (SQLException ex) {

                }

            }

            if(pool!=null)

            {

                 pool.shutDown();

            }

        }

 

    }

}

 

运行所得结果：

Cost Time of Query from PostGreSQL (ms):25

Cost Time of Get from MemCached (ms):8

 

-----data from PostGreSQL------

Net-192.168.0.0/24

Windows

Net-211.144.207.8/29

Net-10.1.70.0/24

Net-10.1.40.0/24

Net-10.1.30.0/24

Net-10.1.20.0/22

。。。。。。。。。。。。。。。。。。。。。。。。。。。

 

-----data from MemCached------

Net-192.168.0.0/24

Windows

Net-211.144.207.8/29

Net-10.1.70.0/24

Net-10.1.40.0/24

Net-10.1.30.0/24

Net-10.1.20.0/22

。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。

 

多运行几次，比较二者消耗时间的差异：

 

 Cost Time of Query from PostGreSQL (ms):17

 Cost Time of Get from MemCached (ms):8

 

Cost Time of Query from PostGreSQL (ms):18

Cost Time of Get from MemCached (ms):8

 

Cost Time of Query from PostGreSQL (ms):16

Cost Time of Get from MemCached (ms):7

 

Cost Time of Query from PostGreSQL (ms):20

Cost Time of Get from MemCached (ms):7

 

 

可以从PostGreSQL中查询数据所消耗的时间大约是从MemCached中查询的所消耗的两倍。因为数据库表记录比较少，所以性能提升不明显。