Crawls take a longer time to be completed when you use a third-party single-threaded IFilter in SharePoint Portal Server 2003

Consider the following scenario in Microsoft Office SharePoint Portal Server 2003. You use a third-party single-threaded IFilter for files that have certain file name extensions. When you perform an incremental update or a full update of content on the portal site, it takes a longer time for the crawl to be completed. When you view the gatherer log after the update operation is completed, some files in document libraries have a Retry status. That is, you see entries that are similar to the following for some files:

This issue occurs because the Mssdmn.exe process in SharePoint Portal Server 2003 copies a file from the source to the temporary folder on the server two times instead of one time. SharePoint Portal Server 2003 does this if a single-threaded IFilter is required for the file that is being copied.

Note When you see many entries that have a Retry status, the third-party IFilter may be single threaded. While this is not the only reason that you may see a Retry status in the gatherer log, it is the most common reason.

How to obtain the hotfix

This issue is fixed in the SharePoint Portal Server 2003 post-Service Pack 1 Hotfix Package that is dated February 9, 2005. For additional information, click the following article number to view the article in the Microsoft Knowledge Base:

Add the WSSSingleThreadedFilterExtensions registry entry

To enable this hotfix after you install it, first add the WSSSingleThreadedFilterExtensions registry entry to the following registry subkey:Then, specify the file name extensions that you want to associate with the single-threaded IFilter. The single-threaded IFilter is used for files in Windows SharePoint Services document libraries that have file name extensions that you specify.

Warning If you use Registry Editor incorrectly, you may cause serious problems that may require you to reinstall your operating system. Microsoft cannot guarantee that you can solve problems that result from using Registry Editor incorrectly. Use Registry Editor at your own risk.
To enable this hotfix, follow these steps:

1. Add the WSSSingleThreadedFilterExtensions registry entry to the following registry subkey, and then specify the file name extensions that you want:
   HKEY_LOCAL_MACHINE\Software\Microsoft\SPSSearch\Gathering Manager
   To do this, follow these steps:
   1. Click Start, click Run, type regedit in the Open box, and then click OK.
   2. Locate and then click the following registry subkey:
      HKEY_LOCAL_MACHINE\Software\Microsoft\SPSSearch\Gathering Manager
   3. On the Edit menu, point to New, and then click String Value.
   4. Type WSSSingleThreadedFilterExtensions, and then press ENTER.
   5. Right-click WSSSingleThreadedFilterExtensions, and then click Modify.
   6. In the Value data box, type the file name extensions that you want. The following are two things to consider when you type file name extensions:
      • Do not use a period character (.) before each file name extension that you type.
      • Separate each file name extension with a semicolon character (;).
      For example, if you want to use the single-threaded filter for .jpg files, for .pdf files, and for .gif files, type the following line in the Value data box:
      jpg;pdf;gif
   7. Click OK, and then click Exit on the File menu to quit Registry Editor.
2. Restart the Microsoft SharePointPS Search service. To do this, follow these steps:
   1. Click Start, click Run, type cmd, and then click OK.
   2. Stop the Microsoft SharePointPS Search service. To do this, type net stop sharepointpssearch at the command prompt, and then press ENTER.
   3. Start the Microsoft SharePointPS Search service. To do this, type net start sharepointpssearch at the command prompt, and then press ENTER.

For more information about IFilters in SharePoint Portal Server 2003, see the "Managing file types" topic in the "Administration" chapter of Microsoft Office SharePoint Portal Server 2003 Administrator's Guide. Specifically, look for the "Managing search settings for the portal" section that is in the "Managing search settings" section. The Microsoft Office SharePoint Portal Server 2003 Administrator's Guide (Administrator's Help.chm) is located in the Docs folder in the root folder of the SharePoint Portal Server 2003 CD.