We have a server that locks up when users perform a restricted search. The information store crashes, locking up the server, and producing an RPC error in the event log with references to a user mailbox. The immediate remedy is to kill the user's Outlook session and ultimately reboot. This particular server has lots of white space. So the question is, will excessive white space affect user performance and contribute to lockups? Exchange 2007 Ent cluster 2008 R2 there are 3 databases - 300G, 250G and 220G (770G), but the actual total user database size is 250G so there is over 500GB of white space. Thanks

I dont think alot of white space in of itself could cause that but if I had that much free space in a database, I would be moving all those mailboxes to a new database and removing the old one. A new database may be just the fix.

Thanks Andy and I agree but the issue is, we dont want to go through the trouble of moving these users to then find that there is no performance change. I wonder if there is a way to quantify the white space issue.

Hi FRIco00, When you have more white space in the database, you can run a offline defragmentation on the database which will remove or clear the white space and keeps the database intact. Ofcourse this will help to improve the performace atleast to some extent. To perform an offline defragmentation, you need to dismount the database and run the following command from the command prompt eseutil /d "path of the database file (.edb)" example: eseutil /d "C:\Program Files\Microsoft\Exchange Server\Mailbox\First Storage Group\Mailbox Database.edb"

Hi , Would you post the detail event log information for RPC error ? And if you want to clean up white space, please understand the following article . Cleaning up whitespace in exchange: http://blogs.technet.com/b/messaging_and_beyond/archive/2012/05/10/cleaning-up-whitespace-in-exchange.aspxWendy Liu TechNet Community Support

Log Name: Application Source: MSExchangeIS Date: 10/11/2012 4:06:50 PM Event ID: 10027 Task Category: General Level: Error Keywords: Classic User: N/A Computer: Server.Domain.com Description: There are 5 RPC requests for the mailbox "06fa3cbc-bb1d-45b6-8658-2a9189b96068" on the database "/o=MAIL/ou=Exchange Administrative Group (FYDIBOHF23SPDLT)/cn=Configuration/cn=Servers/cn=Server/cn=Microsoft Private MDB" that take abnormally long time to complete. It may be indicative of performance problems with your server.

Karthick, Defrags are really not supported for very large databases since it can take too long to defrag a 300GB database (at a rate of 4-6 GB/hour). It would be better to move the mailboxes and delete the empty database, but the question is, can large amounts of whitespace potentially hinder performance and can it cause/contribute to RPC errors?

If you have to much white space, your backup window have to be bigger. If you reduce whitespace, backup of all mailbox databases will take less, and when you wan to restore mailbox database this will also take less time than now. If I had so much whitespace, I would remove it specially because of backup and restore time. Remigiusz ExchangeBlog

Hi , Please try enabling user authentication and test again. The following similar issue for your reference. Cannot open your default e-mail folder. Microsoft Exchange is not available. Either there are network problems or the Exchange server is down for maintenance: http://social.technet.microsoft.com/Forums/en-US/exchange2010/thread/bfb50d8e-7df7-41ff-ac7a-53615ac748b6/Wendy Liu TechNet Community Support

yes, large amounts of whitespace potentially affects performance. so u can go with the plan of moving mailboxes.

OK, so now the hard question: How and why? White space is technically empty previously used space created by removing mailboxes, users archiving their mail etc... Thanks

On Thu, 25 Oct 2012 14:44:52 +0000, Karthick Amir wrote: >yes, large amounts of whitespace potentially affects performance. so u can go with the plan of moving mailboxes. Whitespace may affect the time it takes to make a backup of (and to restore a) mailbox server, but other than that whitepace is simply unused space within a database. Where did you get the information that empty space will have an adverse effect on performance? --- Rich Matheisen MCSE+I, Exchange MVP --- Rich Matheisen MCSE+I, Exchange MVP