一、Linux下MemCached安裝和啟動(dòng)

如果是centos可以yum安裝

# yum install libevent-devel

如果不支持yum的系統(tǒng)，可以這樣裝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

繼續(xù)安裝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

安裝完后啟動(dòng)memcached并分配1024m內(nèi)存

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

-d選項(xiàng)是啟動(dòng)一個(gè)守護(hù)進(jìn)程，
-m是分配給Memcache使用的內(nèi)存數(shù)量，單位是MB，我這里是10MB，
-u是運(yùn)行Memcache的用戶，我這里是root，
-l是監(jiān)聽的服務(wù)器IP地址，如果有多個(gè)地址的話，我這里指定了服務(wù)器的IP地址10.32.33.120，
-p是設(shè)置Memcache監(jiān)聽的端口，我這里設(shè)置了12000，最好是1024以上的端口，
-c選項(xiàng)是最大運(yùn)行的并發(fā)連接數(shù)，默認(rèn)是1024，我這里設(shè)置了256，按照你服務(wù)器的負(fù)載量來設(shè)定，
-P是設(shè)置保存Memcache的pid文件，我這里是保存在 /tmp/memcached.pid，

將memcached加入啟動(dòng)項(xiàng)

# 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鍵，再輸入

：wq

保存退出

查看是否啟動(dòng)memcached

獲取運(yùn)行狀態(tài)：echo stats | nc 10.32.33.120 11211(可以查看出pid) 或使用ps -ef|grep memcached

如果要結(jié)束Memcache進(jìn)程，執(zhí)行：

# kill `cat /tmp/memcached.pid`

也可以

#kill –9 進(jìn)程號

二、連接到 memcached

連接到 memcached：
telnet ip 端口，如telnet 10.32.33.120 11211
stats查看狀態(tài)，flush_all:清楚緩存
查看memcached狀態(tài)的基本命令，通過這個(gè)命令可以看到如下信息：
STAT pid 22459 進(jìn)程ID
STAT uptime 1027046 服務(wù)器運(yùn)行秒數(shù)
STAT time 1273043062 服務(wù)器當(dāng)前unix時(shí)間戳
STAT version 1.4.4 服務(wù)器版本
STAT pointer_size 64 操作系統(tǒng)字大小(這臺服務(wù)器是64位的)
STAT rusage_user 0.040000 進(jìn)程累計(jì)用戶時(shí)間
STAT rusage_system 0.260000 進(jìn)程累計(jì)系統(tǒng)時(shí)間
STAT curr_connections 10 當(dāng)前打開連接數(shù)
STAT total_connections 82 曾打開的連接總數(shù)
STAT connection_structures 13 服務(wù)器分配的連接結(jié)構(gòu)數(shù)
STAT cmd_get 54 執(zhí)行g(shù)et命令總數(shù)
STAT cmd_set 34 執(zhí)行set命令總數(shù)
STAT cmd_flush 3 指向flush_all命令總數(shù)
STAT get_hits 9 get命中次數(shù)
STAT get_misses 45 get未命中次數(shù)
STAT delete_misses 5 delete未命中次數(shù)
STAT delete_hits 1 delete命中次數(shù)
STAT incr_misses 0 incr未命中次數(shù)
STAT incr_hits 0 incr命中次數(shù)
STAT decr_misses 0 decr未命中次數(shù)
STAT decr_hits 0 decr命中次數(shù)
STAT cas_misses 0 cas未命中次數(shù)
STAT cas_hits 0 cas命中次數(shù)
STAT cas_badval 0 使用擦拭次數(shù)
STAT auth_cmds 0
STAT auth_errors 0
STAT bytes_read 15785 讀取字節(jié)總數(shù)
STAT bytes_written 15222 寫入字節(jié)總數(shù)
STAT limit_maxbytes 1048576 分配的內(nèi)存數(shù)（字節(jié)）
STAT accepting_conns 1 目前接受的鏈接數(shù)
STAT listen_disabled_num 0
STAT threads 4 線程數(shù)
STAT conn_yields 0
STAT bytes 0 存儲item字節(jié)數(shù)
STAT curr_items 0 item個(gè)數(shù)
STAT total_items 34 item總數(shù)
STAT evictions 0 為獲取空間刪除item的總數(shù)

三、c#調(diào)用

MemCache管理操作類,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管理操作類
    /// </summary>
    public sealed class MemCachedManager
    {
        #region 靜態(tài)方法和屬性
        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;//初始化鏈接數(shù)
            pool.MinConnections = memCachedConfigInfo.MinConnections;//最少鏈接數(shù)
            pool.MaxConnections = memCachedConfigInfo.MaxConnections;//最大連接數(shù)
            pool.SocketConnectTimeout = memCachedConfigInfo.SocketConnectTimeout;//Socket鏈接超時(shí)時(shí)間
            pool.SocketTimeout = memCachedConfigInfo.SocketTimeout;// Socket超時(shí)時(shí)間
            pool.MaintenanceSleep = memCachedConfigInfo.MaintenanceSleep;//維護(hù)線程休息時(shí)間
            pool.Failover = memCachedConfigInfo.FailOver; //失效轉(zhuǎn)移(一種備份操作模式)
            pool.Nagle = memCachedConfigInfo.Nagle;//是否用nagle算法啟動(dòng)socket
            pool.HashingAlgorithm = HashingAlgorithm.NewCompatibleHash;
 
            pool.Initialize();

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

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

        /// <summary>
        /// 客戶端緩存操作對象
        /// </summary>
        public static MemcachedClient CacheClient
        {
            get
            {
                if (mc == null)
                    CreateManager();

                return mc;
            }
        }

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

    }
}

cache操作接口類ICacheStrategy.cs（為了方便擴(kuò)展其他的cache）：

using System;
using System.Text;

namespace Plugin.Cache
{
    /// <summary>
    /// 公共緩存策略接口
    /// </summary>
    public interface ICacheStrategy
    {
        /// <summary>
        /// 添加指定ID的對象
        /// </summary>
        /// <param name="objId">緩存鍵</param>
        /// <param name="o">緩存對象</param>
        void AddObject(string objId, object o);
      
        /// <summary>
        /// 移除指定ID的對象
        /// </summary>
        /// <param name="objId">緩存鍵</param>
        void RemoveObject(string objId);
        /// <summary>
        /// 返回指定ID的對象
        /// </summary>
        /// <param name="objId">緩存鍵</param>
        /// <returns></returns>
        object RetrieveObject(string objId);
        /// <summary>
        /// 到期時(shí)間,單位：秒
        /// </summary>
        int TimeOut { set;get;}
   }
}

MemCached.cs類

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

namespace Plugin.Cache
{
	/// <summary>
	/// 默認(rèn)緩存管理類,默認(rèn)用memcached
	/// </summary>
    public class MemCached : ICacheStrategy
	{	
		/// <summary>
        /// 設(shè)置到期相對時(shí)間[單位: 秒] 
		/// </summary>
        public int TimeOut { set; get; }
		
		/// <summary>
		/// 加入當(dāng)前對象到緩存中
		/// </summary>
		/// <param name="objId">對象的鍵值</param>
		/// <param name="o">緩存的對象</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>
		/// 刪除緩存對象
		/// </summary>
		/// <param name="objId">對象的關(guān)鍵字</param>
        public virtual void RemoveObject(string objId)
		{
            if (MemCachedManager.CacheClient.KeyExists(objId))
                MemCachedManager.CacheClient.Delete(objId);
		}


		/// <summary>
		/// 返回一個(gè)指定的對象
		/// </summary>
		/// <param name="objId">對象的關(guān)鍵字</param>
		/// <returns>對象</returns>
        public virtual object RetrieveObject(string objId)
		{
            return MemCachedManager.CacheClient.Get(objId);
		}

    }
}

實(shí)體類MemCachedConfigInfo.cs

using Yintai.Plugin.Common;

/// <summary>
/// MemCached配置信息類文件
/// </summary>

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

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

        private int _intConnections;

        /// <summary>
        /// 初始化鏈接數(shù)
        /// </summary>
        public int IntConnections
        {
            get { return _intConnections > 0 ? _intConnections : 3; }
            set { _intConnections = value; }
        }

        private int _minConnections;

        /// <summary>
        /// 最少鏈接數(shù)
        /// </summary>
        public int MinConnections
        {
            get { return _minConnections > 0 ? _minConnections : 3; }
            set { _minConnections = value; }
        }

        private int _maxConnections;

        /// <summary>
        /// 最大連接數(shù)
        /// </summary>
        public int MaxConnections
        {
            get { return _maxConnections > 0 ? _maxConnections : 5; }
            set { _maxConnections = value; }
        }

        private int _socketConnectTimeout;

        /// <summary>
        /// Socket鏈接超時(shí)時(shí)間
        /// </summary>
        public int SocketConnectTimeout
        {
            get { return _socketConnectTimeout > 1000 ? _socketConnectTimeout : 1000; }
            set { _socketConnectTimeout = value; }
        }

        private int _socketTimeout;

        /// <summary>
        /// socket超時(shí)時(shí)間
        /// </summary>
        public int SocketTimeout
        {
            get { return _socketTimeout > 1000 ? _maintenanceSleep : 3000; }
            set { _socketTimeout = value; }
        }

        private int _maintenanceSleep;

        /// <summary>
        /// 維護(hù)線程休息時(shí)間
        /// </summary>
        public int MaintenanceSleep
        {
            get { return _maintenanceSleep > 0 ? _maintenanceSleep : 30; }
            set { _maintenanceSleep = value; }
        }

        private bool _failOver;

        /// <summary>
        /// 鏈接失敗后是否重啟,詳情參見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算法啟動(dòng)socket
        /// </summary>
        public bool Nagle
        {
            get { return _nagle; }
            set { _nagle = value; }
        }
    }
}

實(shí)現(xiàn)代碼完了，下面就是把配置文件memcached.config反序列化成實(shí)體方法

用MemCachedConfig.cs實(shí)現(xiàn)配置文件的載入和讀取LoadConfig是載入配置，SetConfig是保存配置，GetConfig是獲取配置，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>
        /// 獲取配置
        /// </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代碼如下：

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

namespace Plugin.Common
{
	/// <summary>
	/// SerializationHelper 的摘要說明。
	/// </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">對象類型</param>
		/// <param name="filename">文件路徑</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">對象</param>
		/// <param name="filename">文件路徑</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">對象</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;
            }
        }
	}
}

最后配置文件類似這樣的：

<?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>

使用時(shí)調(diào)用方法：

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

這個(gè)方法通過LoadConfig把配置加載進(jìn)來，反序列化成MemCachedConfigInfo實(shí)體并放入私有靜態(tài)變量config 中，并通過GetConfig() 獲取config，然后MemCachedManager類通過private static MemCachedConfigInfo memCachedConfigInfo = MemCachedConfig.GetConfig();方法獲取到配置了。