#Memcached系列#（2）在Windows环境下安装Memcached

南天一柱

　　本篇文章主要是讲如何在Windows操作系统上安装Memcached。
　　原文地址：Installing Memcached on Windows
　　在上一篇文章当中，主要先简述了一下Object Caching存在的缺点，接着又说明了一下Memcached可以避免这些缺点，最后，说Memcached的分为两部分：Memcached Server和Memcached Client两部分。本文，就是讲述Memcached Server如何安装。
　　值得注意的是，Memcached的windows binary主要有两个主要来源：Jellycan和Northscale。之所以强调这个问题，是因为今天上午和下午一直没有安装成功，到后来才发现有这个差异，发现这个差异之后，才安装成功了。
　　【Memcached的简介】Memcached is a high performance, in-memory key-value store or caching system. Its main purpose is to speed up web applications by caching database queries, contents, or other computed results.
　　【Memcached的由来】Memcached is originally a linux application, but since it is open-source, it has been compiled for windows. 【Memcached的两个主要来源】There are two major sources for the pre-built windows binary: Jellycan and Northscale, and both versions can be used. The following are the download links for the memcached windows binaries:
　　http://code.jellycan.com/files/memcached-1.2.5-win32-bin.zip
　　http://code.jellycan.com/files/memcached-1.2.6-win32-bin.zip
　　http://downloads.northscale.com/memcached-win32-1.4.4-14.zip
　　http://downloads.northscale.com/memcached-win64-1.4.4-14.zip
　　http://downloads.northscale.com/memcached-1.4.5-x86.zip
　　http://downloads.northscale.com/memcached-1.4.5-amd64.zip
　　在本文的结尾处，有这6个版本的打包附件，还有一个地址：http://blog.elijaa.org/2010/10/15/memcached-for-windows/
　　【在1.4.5之前的版本，可以将Memcached安装为Windows的服务】In versions earlier than 1.4.5, memcached can install itself as a service. 【在1.4.5之后，Memcached就不能再安装为Windows服务了】However, the ability to run memcached as a service is removed since version 1.4.5. 【因此，安装步骤也分为两部分】Therefore, the installation steps are divided into two categories, part A for memcached prior to version 1.4.5. and part B for memcached version 1.4.5 and later.
A) Installation of memcached < 1.4.5:

• 　　Extract the memcached windows binary to any directroy.
  
• 　　In versions earlier than 1.4.5, memcached can install itself as a service. Run a command prompt with elevated privileges, and type:
  c:\memcached\memcached.exe -d install　　* Replace c:\memcached\memcached.exe with the actual path of your installation.
  
• 　　Then, start or stop the memcached service with the following command:
  c:\memcached\memcached.exe -d start　　
  c:\memcached\memcached.exe -d stop
  
• 　　To change the configuration of memcached, run regedit.exe and navigate to the key "HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\memcached". Suppose you wish to increase the memory limit of memcached, edit the value of ImagePath to the following:
  "c:\memcached\memcached.exe" -d runservice -m 512　　* Besides '-m 512', you may also append other memcached parameters to the path. Run "c:\memcached\memcached.exe -h" to view the list of available parameters.
  
• 　　Meanwhile, to uninstall the memcached serivce, run the following command:
  c:\memcached\memcached.exe -d uninstall
  

B) Installation of memcached >= 1.4.5:

• 　　Extract the memcached windows binary to any directroy.
  
• 　　In version 1.4.5 or later, memcached cannot run as a service. It must be started as a normal process using the task scheduler. To configure the memcached process to run automatically every time windows start, run a command prompt and type the following:
  schtasks /create /sc onstart /tn memcached /tr "'c:\memcached\memcached.exe' -m 512"　　* Replace c:\memcached\memcached.exe with the actual path of your installation.
  　　** Besides '-m 512', you may also append other memcached parameters to the path. Run "c:\memcached\memcached.exe -h" to view the list of available parameters.
  
• 　　Meanwhile, to remove the scheduled memcached task, run the following command:
  schtasks /delete /tn memcached
  

　　补充一下常用设置
　　常用设置：
　　-p <num>          监听的端口
　　-l <ip_addr>      连接的IP地址, 默认是本机
　　-d start          启动memcached服务
　　-d restart        重起memcached服务
　　-d stop|shutdown  关闭正在运行的memcached服务
　　-d install        安装memcached服务
　　-d uninstall      卸载memcached服务
　　-u <username>     以<username>的身份运行 (仅在以root运行的时候有效)
　　-m <num>          最大内存使用，单位MB。默认64MB
　　-M                内存耗尽时返回错误，而不是删除项
　　-c <num>          最大同时连接数，默认是1024
　　-f <factor>       块大小增长因子，默认是1.25
　　-n <bytes>        最小分配空间，key+value+flags默认是48
　　-h                显示帮助
Memcached statistics
　　To view the statistics for memcached, bring up a telnet connection to memcached by the command:
telnet 127.0.0.1 11211　　Then, type statsand enter.
　　Here is an explanation of the different memcached stats.
NameTypeMeaningNameTypeMeaningpid32uProcess>Source: https://github.com/memcached/memcached/blob/master/doc/protocol.txt　　还有一个地方可以下载：http://blog.elijaa.org/2010/10/15/memcached-for-windows/
　　This post contains various binaries versions of Memcached for Windows as finding some of them may be difficult.
Memcached 1.2.X
　　Memcached 1.2.4 for Windows (32 Bits) : memcached 1.2.4 win32.zip
　　Memcached 1.2.5 for Windows (32 Bits) : memcached 1.2.5 win32.zip
　　Memcached 1.2.6 for Windows (32 Bits) : memcached 1.2.6 win32.zip
Memcached 1.4.X
　　Memcached 1.4.2 for Windows (32 Bits) : memcached 1.4.2 win32.zip
　　Memcached 1.4.4 for Windows (32 Bits) : memcached 1.4.4 win32.rar
　　Memcached 1.4.5 for Windows (32 Bits) : memcached 1.4.5 win32.zip
　　Memcached 1.4.5 for Windows (64 Bits) : memcached 1.4.5 win64.zip
Credits
　　All credits goes to Jellycan for 1.2.5 and 1.2.6 and Northscale (now Membase) for 1.4.X.