Community Server性能优化小结

第一阶段：

1、在Community Server的各个.config配置中，象优化WINDOWS的“服务”一样，把不必要的JOB先false掉

2、把存储到数据库的附件/图片之类的，存储到物理目录上去，主要有forums/blogs/photos/files...

把CommunityServer.config中的enableDataStoreStorage="true"替换成enableDataStoreStorage="false"

3、优化SQL Server数据库，让Community Server占用的Size减下来，这部份因为CS先天涉及到的关联太多了，所以，SQL Script比较复杂，优化还在继续，等待第一阶段的优化完成之后，我再写一个比较完整的SQL Script出来和大家分享，请大家关注一下。

第1，2、3步，大家可以先尝试优化一下，可以明显地感觉到优化后的效果。

第二阶段：

服务器上启用HTTP压缩，这样，服务器的性能就有了很大的提高，响应和访问的速度就会更快。

这是一个MS的MVP老外介绍的办法(原文附后)，很管用，大家照着操作就是了。

当然，如果你是虚拟主机用户，不能操作主机，那就没办法了。

第三阶段：

更换部分Moudle。
譬如搜索，换成支持中文的，虽然网上已经有相关文章，但似乎都不太好。正在研究中～～

附：
IIS Compression in IIS6.0

Hold on to your hats folks. If you don't have compression installed on your web server, either IIS Compression or a 3rd party, and you have IIS6.0 and pay for bandwidth you're missing out on something good.

In the day of IIS5 and earlier the compression built into IIS had various issues and was really not worth implementing. To enable compression you would need to go with a 3rd party solution like www.port80software.com or www.xcompress.com. This has all changed in IIS6! At www.orcsweb.com we've been running IIS6.0 compression on some servers for a number of month with few issues, just huge performance and bandwidth benefits.  Expect upwards of 4 times the compression which directly translates to bandwidth savings.  This means faster loading of pages for the end user also.  The only time we had to disable it was for a custom audio application for one of our clients that didn't work with compression.  I'll mention at the end of this how to disable compression for an individual site.

First, for those unfamiliar with what IIS6.0 is and how to get it: IIS6.0, short for Internet Information Services 6.0, is the web software that comes with Windows Server 2003. So if you run IIS on W2K3 then you have IIS6.0. If you're wondering if you can get it apart from W2K3, sorry the answer is 'no'.

One of the issues still there today with compression in IIS is that there isn't a nice interface to manage it. It's not as straight forward as other features of IIS. No need to worry though, I'll explain the ins and outs below of how to implement this properly. I set out to implement IIS Compression a number of months ago and had a hard time finding good information about it. I did find one great post here: http://dotnetguy.techieswithcats.com/archives/003475.shtml. I've since jumped into this subject in more depth and have two things to add to Brad Wilson's article. One, an iisreset is required as I'll mention below but also there is another setting that is required for compression to be more practical for dynamic compression. The other link worth bookmarking is: http://www.microsoft.com/technet/treeview/default.asp?url=/technet/prodtechnol/windowsserver2003/proddocs/standard/ref_prog_iaorefcompschs.asp. (I won't make any promises that this link will always work, Microsoft seems to change their links to documents all the time)

To make it easier I'll include everything needed to properly enable IIS Compression below even though I'll repeat what Brad Wilson said.

First, before anything else, backup the metabase.  This is done by right-clicking on the server in the IIS snap-in and selecting All Tasks -> Backup/Restore Configuration.  The rest is straight forward.

Create Compression Folder (optional)

The first thing I do is create a folder on the D drive where the static file compression will be cached. I call it ASPNetCompressTemp but you can call it anything you want or leave the default of “%windir%\IIS Temporary Compressed Files” if that works for you. The IUSR_{machinename} will need write permission to the folder. If you use custom anonymous users, make sure to assign the proper user. IIS will still work even if the permissions are wrong but the compression won't work properly. Once running, it's worth double checking Event Viewer to see if any errors are occurring that keep IIS Compression from working.

Enable Compression in IIS

- From the IIS snap-in, right-click on the Web Sites node and click on Properties
- Select the Service tab - Enable Compress application files
- Enable Compress static files
- Change Temporary Directory to the folder that you created above, or leave it at it's default
- Set the max size of the temp folder to something that the hard drive can handle. i.e. 1000. 
- Save and close the Web Site Properties dialog

Note: The temporary compress directory is only used for static pages.  Dynamic pages aren't saved to disk and are recreated every time so there is some CPU overhead used on every page request for dynamic content.

Create a Web Service Extension (WSE)

IIS6.0 is much more proactive than IIS5 in regards to security and introduces a new feature called Web Service Extensions. This is great but means an extra step.

- In the IIS snap-in select Web Service Extensions
- Create a new web service extension
- Call it HTTP Compression
- Point it to c:\windows\system32\inetsrv\gzip.dll
- Check the Set status checkbox so that it is enabled (Allowed) Enable Direct Metabase Edit (optional) One of many large improvement with IIS 6 is that the metabase isn't in binary format anymore and can be edited directly using Notepad or any other tools that allows editing an XML file. Personally I prefer to enable Direct Metabase Edit so that I can edit it and the change takes affect immediately. If this isn't enabled, you will need to stop and start the web services for any changes to take affect. Of course, like editing the windows registry there is always the chance of something going wrong so be careful. Unlike the windows registry though, if you make a mistake and the metabase is saved and doesn't conform to the proper XML scheme, it won't take affect, so thanks to the IIS team it's quite difficult to completely mess up the metabase. To enable this, right-click on the server (top level) in the IIS snap-in. There is a single checkbox that needs to be checked. This part couldn't get easier.

Now for the metabase changes

Now we move away from the IIS snap-in GUI and have to get our hands dirty. (well, as dirty as they can get when dealing with computer software)

Here is where the IIS team either wanted to make things a bit difficult or they didn't get the changes done in time for the final release of IIS6. Actually it's the latter as I've heard rumor that they will be improving on the GUI over time.

Note: If you want to save yourself the hassle of understanding all of this, purchase ZipEnable from Port80 Software.  http://www.port80software.com/products/zipenable/.  This is a tool that gives you full control down to the folder and file level and embeds itself into the IIS MMC snap-in, making things much easier.  I haven't tried this out so I can't attest to it myself but Port80 Software is a company that Microsoft has recommended for years to use if you want HTTP Compression.

There are a couple ways to do this. One is to edit the metabase directly using Notepad and the other is using adsutil.vbs usually found in your C:\Inetpub\AdminScripts folder. I'll explain the direct edit method because I find it's easier to picture and understand what is happening then using a command-line tool.

- Open the metabase located at C:\Windows\system32\inetsrv\metabase.xml in Notepad
- Search for <IIsCompressionScheme 
- There should be two of them, one for deflate and one for gzip.  Basically they are two means of compression that IIS supports.
- First thing to do is add aspx,  asmx, php and any other extension that you need to the list extensions in HcScriptFileExtensions.  Make sure to follow the existing format carefully, an extra space will keep this from working correctly.  Do this for both deflate and gzip.
- Now for the other thing commonly missed.  HcDynamicCompressionLevel has a default value of 0.  Basically this means at if you did everything else right, the compression for dynamic contact is at the lowest level.  The valid range for this is from 0 to 10.  I had the opportunity of receiving an internal testing summary from Chris Adams from Microsoft regarding the compression level -vs- CPU usage which showed that the CPU needed for levels 0 - 9 is fairly low but for level 10 it hits the roof.  Yet the compression for level 9 is nearly as good as level 10.  I write all this to say that I recommend level 9 so make sure to change HcDynamicCompressionLevel to 9.  Do this for both deflate and gzip.

- Just one thing left.  There are two settings that required the World Wide Web Publishing Service (WWW service) be reset.  One was enabling compression and the other was HcDynamicCompressionLevel.  Even with its shortcomings I simply do an iisreset from the command prompt but you can reset the service whichever way you prefer.

That's it folks.  I didn't promise it would be easy but hopefully I was straight forward enough in my steps to keep this from being too difficult.

I should mention it is possible to disable or enable compression at the site or sub-folder level.  This time I'll be lazy and tell you the adsutil.vbs way to do this but it can be done directly using Notepad and editing the metabase directly if you prefer.  From the command prompt enter the following two commands and be sure to replace site# with the siteID that you are changing:

发现CommunityServer（以下简称CS）系统在数据量多和访问量大的情况下对资源的占用还是比较厉害，尤其是Sqlserver，于是尝试进行对其进行优化，以下是对其优化的一个过程和参考方案，算是抛砖引玉：

针对SQLServer资源占用较高的情况，开始具体分析到底是哪些存储过程比较占用资源，在服务器上启动SQLServer的Profiler工具，对所有执行的存储过程、SQL进行记录，在记录了两个小时的日志后，下载到本地进行分析，分析结果发现，对于最新图片、分页读取帖子、最新Blog这类的存储过程执行较为频繁，且执行时间较长，尤其是其中的“最新图片”的存储过程，因为join了若干table，所以执行时间特别长，如果重启SQLServer后执行甚至有时超过20秒，所以在第一次打开首页时特别慢，当缓存更新后也是特别慢。

因为这部分内容都更新相对比较频繁，所以即使Cache也效果不是很理想。以其中论坛部分为例，首先要从cs_Threads表的几十万条记录中找到符合条件的ThreadID，再从中取出第一页所需要的最新N（假设为20）个ThreadID，然后根据这20个ThreadID从cs_Threads和cs_Posts表进行Join取得最新20篇新帖子，对于第一步：“从cs_Threads表的几十万条记录中找到符合条件的ThreadID”这个的SQL进行优化的难度比较大，而且效果也不是很明显。

对Logo再次分析，发现对于大多数用户来说，一般关注的是最新的帖子，所以大部分对于分页读取帖子的请求多数集中在第一页，就如我们进入一个板块，往往只看第一页的帖子，同样的也包括“最新图片”、“最新Blog”和“最新帖子”。于是有了个初步的想法，对cs_Threads表中，每个SectionID对应的Thread记录都用一个专门的表例如cs_CachedThreads，Cache上M条（M>=N），这个表中每个SectionID对应的Thread只保留最新的M条，并且和cs_Threads表保持同步，这样，cs_CachedThreads表记录一般保持在几千条以内。当需要读取最新的第一页数据时，就从cs_CachedThreads表读取，相对于从几十万记录的cs_Threads表读取来说，执行时间要少很多。

在这样优化一次以后，网站首页和各版面首页的执行效率还是提高不少，SQLServer的性能也有所提高。