Hi, Some users has complained about that Outlook is slow from time to time. And when looked at the server, then everything seems ok.I alsolooking at our Exchange server and i saw that the database files is pretty huge now. And i was just wondering if there is any best practice for how huge you should let this file be before you split them to new mailbox stores just to reduce the size of the other ones. As it is today we have one storage group with three mailbox store's. priv.edb30 GB (first store) priv.stm17 GB (first store) Mailbox Store 2.edb 56 GB (second store) Mailbox Store 2.stm 43 GB (second store) Mailbox Store 3.edb1 GB (third store) Mailbox Store 3.stm0.2 GB (third store) And then we have the public folders. pub.edb 2 GB pub.stm 4GB Is any of this files to huge? And should i cut them info smaller files? Is there any best practice for these? Best Regards, M

They aren't that big to be honest. It's not the size of the databases or individual mailboxes that necessarily cause performance problems but sometimes the number of items in users' core folders such as Inbox, Sent Items, etc. You mention "some" of the users complain - I'd check to see how many items they have in their core folders. Also, you may need to do some performance monitoring on the server, etc.

Thank you for your quick answer Neil. Ok, i can see that two of the users that has complained have 500 MB (4400 total files) respective 150 MB (3600 total files). And that isn't much at all. I have already openedperfmon.msc and looked at some counters such as avg. read/write disk activity. Is there any critical counter I should look at so I can insolate the problem. Best regards, M

Hi Mario, I agree with Neil. About the performance monitoring, you can run perfwiz which has predefined standard set of counters for Exchange 2003. http://www.microsoft.com/downloads/details.aspx?familyid=31fccd98-c3a1-4644-9622-faa046d69214&displaylang=en Then you can use PLA (Performance Analysis of Logs) to scan the perfwiz result for Exchange 2003 and gives you the consolidated html report with the key points. http://www.codeplex.com/PAL http://blogs.technet.com/mikelag/archive/2008/08/20/performance-troubleshooting-using-the-pal-tool.aspx

Dear customer: Is your Exchange server 2000 or 2003? Do the problematic users run Outlook in online mode or cached mode? If they run Outlook in online mode, switch to cached mode and check the effect. First, I should explain .edb and .stm file here: .edb file, also known as the rich text store, is used for storing compressed rich text format as MAPI properties. Edb file contains the store tables which are used by clients when accessing data..stm file, also known as the streaming file, is used for storing native format data, the contiguous sequences of streamed content, without conversion. Emails from the Internet are stored by default in the .stm file. Exchange will convert a message's header to rich text format and store them in the .edb file, so that MAPI clients such as Outlook can use them. If a MAPI client requests a message property other than header later which is stored in .stm file, Exchange will convert it to RTF and place it in the .edb file. After conversion, the message remains in .edb file and are not converted back. That's why usually the .edb file is larger than the .stm file. There is no fixed ratio for the two files. If you have quite a lot emails from the Internet and many of your users are using non-MAPI clients, the .stm file will be quite large. It is common. For database size, the physical size of the database is the total size of both .edb file and .stm file. So your database files are 47, 99, 1.2 GB separately in size. There is no fixed recommended size for database. But, we do recommend a database occupies at most 50% of the logical hard disk space which it stays. Also, you can monitor the following counter: MSExchangeIS\RPC Requests It should be below 30 at all times. MSExchangeIS\RPC Averaged Latency It should be below 50 ms at all times. For more information about Microsoft Exchange Server Performance, please refer to the following article: Troubleshooting Microsoft Exchange Server Performance http://www.microsoft.com/downloads/details.aspx?displaylang=en&FamilyID=8679f6bd-7ff0-41f5-bdd0-c09019409fc0 Hope it helps. Rock Wang - MSFT