Suspect Desktop Search Installed on Clients
Topic Last Modified: 2006-09-05
The Microsoft® Exchange Server Analyzer Tool has determined that you have many users who are using a desktop search engine. Desktop search engines may create many remote procedure calls (RPCs) against a user's mounted mailboxes, as well as substantial traffic against the public folders as these search engines crawl the file structure of the public folder store. Many search engines only crawl the public folders if they are in the user's public folder Favorites list. Therefore, you may or may not see load on the public folder servers from desktop search.
Actions that you can take to mitigate this issue include the following:
Have your users turn off the scanner's Microsoft Office Outlook® features, or limit the scan to just their personal mailbox.
Run Outlook in Cached Exchange Mode so that the scans only affect the local workstation and not the server.
Follow the guidance of Microsoft Knowledge Base article 889086, "You may experience unexpected behavior in a Windows XP-based computer when you try to access public folders on Exchange 2000 Server" (http://go.microsoft.com/fwlink/?linkid=3052&kbid=889086) to obtain the hofix and set the MaxObjsPerMapiSession registry key on computers that are running Exchange Server that are accessed by desktop search users.
To verify if the desktop search application is the cause of high load for a particular user, use Microsoft Exchange Server User Monitor (ExMon) to monitor the RPC operations the search engine's actions, make sure you gather data for an adequate time period (at least five minutes). Then, remove the search engine and run the ExMon tool again. If there is a significant decrease in the RPC rate, you have confirmed that desktop search engine is causing the increase in load. If you observe that the average RPC latency decreases, you have confirmed that the high load resulted in higher RPC latencies.
|RPC latency rates vary considerably throughout the day. Therefore, a five-minute test may be inadequate. You may need to measure for a longer period of time.|
To download ExMon, see the Microsoft Download Center (http://go.microsoft.com/fwlink/?linkid=54983).
For more information about desktop search software, see:
Microsoft Knowledge Base article 905184, "Exchange 2000 Server and Exchange Server 2003 performance may be affected when desktop search engine software is running on Outlook or other MAPI client computers" (http://go.microsoft.com/fwlink/?linkid=3052&kbid=905184).
Microsoft Exchange Team blog, "Are your clients using desktop search engines that index Exchange mailboxes or public folders?" (http://go.microsoft.com/fwlink/?LinkId=54475).
- Microsoft Knowledge Base article 905184, "Exchange 2000 Server and Exchange Server 2003 performance may be affected when desktop search engine software is running on Outlook or other MAPI client computers" (http://go.microsoft.com/fwlink/?linkid=3052&kbid=905184).
For more information about Exchange Server performance, see the Exchange Server 2003 Performance and Scalability Guide (http://go.microsoft.com/fwlink/?LinkId=47576).
For more information about troubleshooting Exchange Server performance issues, see Troubleshooting Microsoft Exchange Server 2003 Performance (http://go.microsoft.com/fwlink/?LinkId=47588).