Best Practices - SharePoint Object Model for Performance Tuning

Follow these articles for SharePoint Object Model for Performance Tuning....!!!

http://blogs.msdn.com/b/sowmyancs/archive/2008/10/26/best-practices-sharepoint-object-model-for-performance-tuning.aspx

Best Practices - BLOB Cache (Configuration & Type of files to Include)

In SharePoint you also have something called the BLOB Cache, which is a disk-based caching mechanism that caches resources on the disk. Normally these resources are files served by a web page and are named Binary Large OBjects (BLOB).

Normally the BLOB cache will cache files served by the web request like images and video clips.

In web.config you’ve got something similar to the following line which lets you know what file types are cached. You can of course add or remove file types here:

<BlobCache  
    location="D:BLOB" 
path=".(gif|jpg|jpeg|jpe|jfif|bmp|dib|tif|tiff|ico|png|wdp|hdp|css|js|asf|avi|flv|m4v|mov|mp3|mp4|mpeg|mpg|rm|rmvb|wma|wmv)$"
    maxSize="10" 
    enabled="false" />

Read more: Configure cache settings for a Web Application (SharePoint Server 2010)
Read more: Configure the BLOB Cache

Best Practices - SharePoint Anti-virus scanning exclusions!!!

Occasionally different anti-virus products can interfere with SharePoint operations. The following is a list of suggested locations to exclude from your AV scanner. Remember, this is merely a suggestion, so use at your own risk!

1.  %PROGRAM FILES%\Common Files\Microsoft Shared\web server extensions\12
2.  %WINNT%\temp
3.  %PROGRAM FILES%\Microsoft Office Server
4.  %WINNT%\Microsoft.NET\Framework\v2.0.50727\Temporary ASP.NET Files\
5.  Documents and Settings\All Users\Application Data\Microsoft\SharePoint\Config\     (the config cache)
6.  %WINNT%\Temp\WebTempDir

UPDATE: We've released a KB that covers this.
http://support.microsoft.com/kb/952167

But is you want to SCAN uploading and downloading of documents in SharePoint, You need to configure Antivirus in Central Administration > Operations > Security Configuration and Select Antivirus.

NOTE: You can activate Antivirus measures only after installing a compatible Antivirus scanner. In a server farm, you must install Antivirus software on every Web front-end server in the server farm.

To enable Antivirus Settings section, Select one or all of the following:

1. Scan documents on upload.
2. Scan documents on download.
3. Allow users to download infected documents.
4. Attempt to clean infected documents.
5. In the Time out scanning after ___ seconds box, type the number of seconds to allow before timing out the scanning process.

NOTE: The default time is 300 seconds, or 5 minutes. This should be enough time to allow the Antivirus processes to finish without affecting performance. The default time is recommended, but you can adjust this time if you are experiencing performance issues.

6. In the Allow scanner to use up to ___ threads box, type the number of threads to allow the scanning process to take up.

NOTE: By default, the number of threads is set to 5, which should be sufficient for even a large number of sites. The default number of threads is recommended, but you can adjust the number of threads if you are experiencing performance issues.

7. Click OK.
   
   
   NOTE: Best Practice is to No need to scan for documents which are getting download from 

   SharePoint, but please note it totally depends upon your business need.

Best Practices - Application Pools Limitation in IIS where SharePoint is Installed!!!

For SharePoint web application content, if you have more than 10 application pools on the same server (see here: http://technet.microsoft.com/en-us/library/cc262787.aspx), you are outside support. You have a choice between sharing application pools between several web applications for performance, or having some *specific* web apps in their own pool. Each time you do this it uses more CPU and RAM resources. However, a separate app pool may make my web app less vulnerable to other web apps crashing on the same server. Generally, I only have separate application pools for web apps when I have a specific security or stability requirement; e.g. my Corporate Published Intranet web app should be separate from the My Sites and Team Sites self-service-site-provisioning ones.


The above content is according to Microsoft Recommendation.

Best Practices - MAXDOP for SharePoint Databases Should be Set to "1"

Theory Says:

0 - Uses the actual number of available CPUs depending on the current system workload. This is the default value and recommended setting for Non-SharePoint SQL DBs.

1 - Suppresses parallel plan generation. The operation will be executed serially.

2-64 - Limits the number of processors to the specified value. Fewer processors may be used depending on the current workload. If a value larger than the number of available CPUs is specified, the actual number of available CPUs is used.