Linux下MemCached安装及c#客户端调用

一、Linux下MemCached安装和启动

如果是centos可以yum安装

# yum install libevent-devel

如果不支持yum的系统，可以这样装libevent

# cd /usr/local/src
# wget http://www.monkey.org/~provos/libevent-1.4.12-stable.tar.gz
# tar vxf libevent-1.4.12-stable.tar.gz
# cd libevent-1.4.12
# ./configure --prefix=/usr/local/libevent
# make && make install

继续安装memcached

# cd /usr/local/src
# wget http://cloud.github.com/downloads/saberma/saberma.github.com/memcached-1.4.4.tar.gz
# tar vxf memcached-1.4.4.tar.gz
# cd memcached-1.4.4
# ./configure --prefix=/usr/local/memcached
# make && make install

安装完后启动memcached并分配1024m内存

/usr/local/memcached/bin/memcached -d -m 1024 –l 10.32.33.120 -p 11211 -u root

-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10.32.33.120，
-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，

将memcached加入启动项

# vi /etc/rc.d/rc.local

在最后加入

/usr/local/memcached/bin/memcached -d -m 1024 –l 10.32.33.120 -p 11211 -u root

按Esc键，再输入

：wq

保存退出

查看是否启动memcached

获取运行状态：echo stats | nc 10.32.33.120 11211(可以查看出pid) 或使用ps -ef|grep memcached

如果要结束Memcache进程，执行：

# kill `cat /tmp/memcached.pid`

也可以

#kill –9 进程号

二、连接到 memcached

连接到 memcached：
telnet ip 端口，如telnet 10.32.33.120 11211
stats查看状态，flush_all:清楚缓存
查看memcached状态的基本命令，通过这个命令可以看到如下信息：
STAT pid 22459 进程ID
STAT uptime 1027046 服务器运行秒数
STAT time 1273043062 服务器当前unix时间戳
STAT version 1.4.4 服务器版本
STAT pointer_size 64 操作系统字大小(这台服务器是64位的)
STAT rusage_user 0.040000 进程累计用户时间
STAT rusage_system 0.260000 进程累计系统时间
STAT curr_connections 10 当前打开连接数
STAT total_connections 82 曾打开的连接总数
STAT connection_structures 13 服务器分配的连接结构数
STAT cmd_get 54 执行get命令总数
STAT cmd_set 34 执行set命令总数
STAT cmd_flush 3 指向flush_all命令总数
STAT get_hits 9 get命中次数
STAT get_misses 45 get未命中次数
STAT delete_misses 5 delete未命中次数
STAT delete_hits 1 delete命中次数
STAT incr_misses 0 incr未命中次数
STAT incr_hits 0 incr命中次数
STAT decr_misses 0 decr未命中次数
STAT decr_hits 0 decr命中次数
STAT cas_misses 0 cas未命中次数
STAT cas_hits 0 cas命中次数
STAT cas_badval 0 使用擦拭次数
STAT auth_cmds 0
STAT auth_errors 0
STAT bytes_read 15785 读取字节总数
STAT bytes_written 15222 写入字节总数
STAT limit_maxbytes 1048576 分配的内存数（字节）
STAT accepting_conns 1 目前接受的链接数
STAT listen_disabled_num 0
STAT threads 4 线程数
STAT conn_yields 0
STAT bytes 0 存储item字节数
STAT curr_items 0 item个数
STAT total_items 34 item总数
STAT evictions 0 为获取空间删除item的总数

三、c#调用

MemCache管理操作类,MemCachedManager.cs文件：

using System;
using System.Collections;
using System.Data;
using System.Data.Common;
using System.IO;
using Memcached.ClientLibrary;
namespace Plugin.Cache
{
    /// <summary>
    /// MemCache管理操作类
    /// </summary>
    public sealed class MemCachedManager
    {
        #region 静态方法和属性
        private static MemcachedClient mc = null;
        private static SockIOPool pool = null;
        private static string[] serverList = null;
        private static MemCachedConfigInfo memCachedConfigInfo = MemCachedConfig.GetConfig();
 
        #endregion

        static MemCachedManager()
        {
            CreateManager();
        }

        private static void CreateManager()
        {
            serverList = memCachedConfigInfo.ServerList;
            pool = SockIOPool.GetInstance(memCachedConfigInfo.PoolName);
            pool.SetServers(serverList);
            pool.InitConnections = memCachedConfigInfo.IntConnections;//初始化链接数
            pool.MinConnections = memCachedConfigInfo.MinConnections;//最少链接数
            pool.MaxConnections = memCachedConfigInfo.MaxConnections;//最大连接数
            pool.SocketConnectTimeout = memCachedConfigInfo.SocketConnectTimeout;//Socket链接超时时间
            pool.SocketTimeout = memCachedConfigInfo.SocketTimeout;// Socket超时时间
            pool.MaintenanceSleep = memCachedConfigInfo.MaintenanceSleep;//维护线程休息时间
            pool.Failover = memCachedConfigInfo.FailOver; //失效转移(一种备份操作模式)
            pool.Nagle = memCachedConfigInfo.Nagle;//是否用nagle算法启动socket
            pool.HashingAlgorithm = HashingAlgorithm.NewCompatibleHash;
 
            pool.Initialize();

            mc = new MemcachedClient();
            mc.PoolName = memCachedConfigInfo.PoolName;
            mc.EnableCompression = false;
        }

        /// <summary>
        /// 缓存服务器地址列表
        /// </summary>
        public static string[] ServerList
        {
            set
            {
                if (value != null)
                    serverList = value;
            }
            get { return serverList; }
        }

        /// <summary>
        /// 客户端缓存操作对象
        /// </summary>
        public static MemcachedClient CacheClient
        {
            get
            {
                if (mc == null)
                    CreateManager();

                return mc;
            }
        }

        public static void Dispose()
        {
            if (pool != null)
                pool.Shutdown();
        }

    }
}

cache操作接口类ICacheStrategy.cs（为了方便扩展其他的cache）：

using System;
using System.Text;

namespace Plugin.Cache
{
    /// <summary>
    /// 公共缓存策略接口
    /// </summary>
    public interface ICacheStrategy
    {
        /// <summary>
        /// 添加指定ID的对象
        /// </summary>
        /// <param name="objId">缓存键</param>
        /// <param name="o">缓存对象</param>
        void AddObject(string objId, object o);
      
        /// <summary>
        /// 移除指定ID的对象
        /// </summary>
        /// <param name="objId">缓存键</param>
        void RemoveObject(string objId);
        /// <summary>
        /// 返回指定ID的对象
        /// </summary>
        /// <param name="objId">缓存键</param>
        /// <returns></returns>
        object RetrieveObject(string objId);
        /// <summary>
        /// 到期时间,单位：秒
        /// </summary>
        int TimeOut { set;get;}
   }
}

MemCached.cs类

using System;
using System.Web;
using System.Collections;
using System.Web.Caching;

namespace Plugin.Cache
{
	/// <summary>
	/// 默认缓存管理类,默认用memcached
	/// </summary>
    public class MemCached : ICacheStrategy
	{	
		/// <summary>
        /// 设置到期相对时间[单位: 秒] 
		/// </summary>
        public int TimeOut { set; get; }
		
		/// <summary>
		/// 加入当前对象到缓存中
		/// </summary>
		/// <param name="objId">对象的键值</param>
		/// <param name="o">缓存的对象</param>
		public virtual void AddObject(string objId, object o)
		{
            if (TimeOut > 0)
            {
                MemCachedManager.CacheClient.Set(objId, o, System.DateTime.Now.AddSeconds(TimeOut));
            }
            else
            {
                MemCachedManager.CacheClient.Set(objId, o);
            }
		}

		/// <summary>
		/// 删除缓存对象
		/// </summary>
		/// <param name="objId">对象的关键字</param>
        public virtual void RemoveObject(string objId)
		{
            if (MemCachedManager.CacheClient.KeyExists(objId))
                MemCachedManager.CacheClient.Delete(objId);
		}


		/// <summary>
		/// 返回一个指定的对象
		/// </summary>
		/// <param name="objId">对象的关键字</param>
		/// <returns>对象</returns>
        public virtual object RetrieveObject(string objId)
		{
            return MemCachedManager.CacheClient.Get(objId);
		}

    }
}

实体类MemCachedConfigInfo.cs

using Yintai.Plugin.Common;

/// <summary>
/// MemCached配置信息类文件
/// </summary>

namespace Plugin
{
    public class MemCachedConfigInfo
    {
        private string[] _serverList;
        /// <summary>
        /// 链接地址
        /// </summary>
        public string[] ServerList
        {
            get { return _serverList; }
            set { _serverList = value; }
        }

        private string _poolName;
        /// <summary>
        /// 链接池名称
        /// </summary>
        public string PoolName
        {
            get { return string.IsNullOrEmpty(_poolName) ? "Yintai.Plugin.Cache.MemCached" : _poolName; }
            set { _poolName = value; }
        }

        private int _intConnections;

        /// <summary>
        /// 初始化链接数
        /// </summary>
        public int IntConnections
        {
            get { return _intConnections > 0 ? _intConnections : 3; }
            set { _intConnections = value; }
        }

        private int _minConnections;

        /// <summary>
        /// 最少链接数
        /// </summary>
        public int MinConnections
        {
            get { return _minConnections > 0 ? _minConnections : 3; }
            set { _minConnections = value; }
        }

        private int _maxConnections;

        /// <summary>
        /// 最大连接数
        /// </summary>
        public int MaxConnections
        {
            get { return _maxConnections > 0 ? _maxConnections : 5; }
            set { _maxConnections = value; }
        }

        private int _socketConnectTimeout;

        /// <summary>
        /// Socket链接超时时间
        /// </summary>
        public int SocketConnectTimeout
        {
            get { return _socketConnectTimeout > 1000 ? _socketConnectTimeout : 1000; }
            set { _socketConnectTimeout = value; }
        }

        private int _socketTimeout;

        /// <summary>
        /// socket超时时间
        /// </summary>
        public int SocketTimeout
        {
            get { return _socketTimeout > 1000 ? _maintenanceSleep : 3000; }
            set { _socketTimeout = value; }
        }

        private int _maintenanceSleep;

        /// <summary>
        /// 维护线程休息时间
        /// </summary>
        public int MaintenanceSleep
        {
            get { return _maintenanceSleep > 0 ? _maintenanceSleep : 30; }
            set { _maintenanceSleep = value; }
        }

        private bool _failOver;

        /// <summary>
        /// 链接失败后是否重启,详情参见http://baike.baidu.com/view/1084309.htm
        /// </summary>
        public bool FailOver
        {
            get { return _failOver; }
            set { _failOver = value; }
        }

        private bool _nagle;

        /// <summary>
        /// 是否用nagle算法启动socket
        /// </summary>
        public bool Nagle
        {
            get { return _nagle; }
            set { _nagle = value; }
        }
    }
}

实现代码完了，下面就是把配置文件memcached.config反序列化成实体方法

用MemCachedConfig.cs实现配置文件的载入和读取LoadConfig是载入配置，SetConfig是保存配置，GetConfig是获取配置，其中用了了序列化和反序列化

MemCachedConfig.cs文件如下：

using System;
using System.Collections.Generic;
using System.Drawing;
using System.Drawing.Imaging;
using System.Linq;
using System.Text;
using System.Web;
using Plugin.Cache;
using Plugin.Common;


namespace Plugin
{
    public class MemCachedConfig
    {
        private static object _lockHelper = new object();
        private static MemCachedConfigInfo config = null;

        public static void LoadConfig(string configfilepath)
        {
            if (config == null)
            {
                lock (_lockHelper)
                {
                    if (config == null)
                    {
                        config = (MemCachedConfigInfo)SerializationHelper.Load(typeof(MemCachedConfigInfo), configfilepath);
                    }
                }
            }
        }

        /// <summary>
        /// 获取配置
        /// </summary>
        /// <param name="anConfig"></param>
        public static MemCachedConfigInfo GetConfig()
        {
            return config;
        }

        #region 私有方法
        public static void SetConfig(MemCachedConfigInfo verifyImageServiceInfoList, string configfilepath)
        {
            SerializationHelper.Save(verifyImageServiceInfoList, configfilepath);
        }

        #endregion
    }
}

SerializationHelper.cs代码如下：

using System;
using System.IO;
using System.Xml.Serialization;
using System.Xml;
using System.Collections.Generic;
using System.Text;

namespace Plugin.Common
{
	/// <summary>
	/// SerializationHelper 的摘要说明。
	/// </summary>
	public class SerializationHelper
	{
        private SerializationHelper()
		{}

        private static Dictionary<int, XmlSerializer> serializer_dict = new Dictionary<int, XmlSerializer>();

        public static XmlSerializer GetSerializer(Type t)
        {
            int type_hash = t.GetHashCode();

            if (!serializer_dict.ContainsKey(type_hash))
                serializer_dict.Add(type_hash, new XmlSerializer(t));

            return serializer_dict[type_hash];
        }


		/// <summary>
		/// 反序列化
		/// </summary>
		/// <param name="type">对象类型</param>
		/// <param name="filename">文件路径</param>
		/// <returns></returns>
		public static object Load(Type type, string filename)
		{
			FileStream fs = null;
			try
			{
				// open the stream...
				fs = new FileStream(filename, FileMode.Open, FileAccess.Read, FileShare.ReadWrite);
				XmlSerializer serializer = new XmlSerializer(type);
				return serializer.Deserialize(fs);
			}
			catch(Exception ex)
			{
				throw ex;
			}
			finally
			{
				if(fs != null)
					fs.Close();
			}
		}


		/// <summary>
		/// 序列化
		/// </summary>
		/// <param name="obj">对象</param>
		/// <param name="filename">文件路径</param>
		public static bool Save(object obj, string filename)
		{
            bool success = false;

			FileStream fs = null;
			// serialize it...
			try
			{
				fs = new FileStream(filename, FileMode.Create, FileAccess.Write, FileShare.ReadWrite);
				XmlSerializer serializer = new XmlSerializer(obj.GetType());
				serializer.Serialize(fs, obj);
                success = true;
			}
			catch(Exception ex)
			{
				throw ex;
			}
			finally
			{
				if(fs != null)
					fs.Close();
			}
            return success;

		}

        /// <summary>
        /// xml序列化成字符串
        /// </summary>
        /// <param name="obj">对象</param>
        /// <returns>xml字符串</returns>
        public static string Serialize(object obj)
        {
            string returnStr = "";
            XmlSerializer serializer = GetSerializer(obj.GetType());
            MemoryStream ms = new MemoryStream();
            XmlTextWriter xtw = null;
            StreamReader sr = null;
            try
            {
                xtw = new System.Xml.XmlTextWriter(ms, Encoding.UTF8);
                xtw.Formatting = System.Xml.Formatting.Indented;
                serializer.Serialize(xtw, obj);
                ms.Seek(0, SeekOrigin.Begin);
                sr = new StreamReader(ms);
                returnStr = sr.ReadToEnd();
            }
            catch (Exception ex)
            {
                throw ex;
            }
            finally
            {
                if (xtw != null)
                    xtw.Close();
                if (sr != null)
                    sr.Close(); 
                ms.Close();
            }
            return returnStr;

        }

        public static object DeSerialize(Type type, string s)
        { 
            byte[] b = System.Text.Encoding.UTF8.GetBytes(s);
            try
            {
                XmlSerializer serializer = GetSerializer(type);
                return serializer.Deserialize(new MemoryStream(b));
            }
            catch (Exception ex)
            {
                throw ex;
            }
        }
	}
}

最后配置文件类似这样的：

<?xml version="1.0"?>
<MemCachedConfigInfo xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema">
  <ServerList>
    <string>10.32.33.120:11211</string>
  </ServerList>
  <PoolName>Plugin.Cache.MemCached</PoolName>
  <IntConnections>3</IntConnections>
  <MinConnections>3</MinConnections>
  <MaxConnections>5</MaxConnections>
  <SocketConnectTimeout>1000</SocketConnectTimeout>
  <SocketTimeout>30</SocketTimeout>
  <MaintenanceSleep>30</MaintenanceSleep>
  <FailOver>true</FailOver>
  <Nagle>false</Nagle>
</MemCachedConfigInfo>

使用时调用方法：

MemCachedConfig.LoadConfig(Server.MapPath("/config/memcached.config"));

这个方法通过LoadConfig把配置加载进来，反序列化成MemCachedConfigInfo实体并放入私有静态变量config 中，并通过GetConfig() 获取config，然后MemCachedManager类通过private static MemCachedConfigInfo memCachedConfigInfo = MemCachedConfig.GetConfig();方法获取到配置了。