For quite some time now we have some performance trouble on Exchange 2003 / Outlook 2003. Our environment:Exchange 2003 SP2 mailbox cluster on Windows server 2003 SP2 (physical servers)4gb ram with /3gb switch+/- 2500 mailboxesBlackberry Enterprise server with 400 BlackberriesAntigen e-mail virus scanningDisabled Mcafee virus scanning (file system)Exchange databases on Netapp storageWhen a user opens a shared calendar in Outlook it may take up to 30 seconds to open the other calendar (and receive a RPC popup). Normal outlook operations like opening mail etc. works quite well. On the server the RPC average latency is too high but I can't figure out what to do about it. On our server it's normal to have an averaged RPC latency of 40/50 with peeks over 100.RPC operations/sec = constant +/- 350 and RPC requests = low at <5. This low number of RPC requests indicates to me that our server is able to handle the requested RPC operations (?) I ran the best practice analyzer and the troubleshooting assistent. The troubleshooting assistent tells me there is a high user RPC activity (I know) and that the Memory Free System Page Table Entries is 5819 which is too low according to the troubleshooting assistent.Antigen is eating 1,3gb memory but when I shut it down I see no performance improvement, I also can't see how I could lower the Antigen memory consumption.So resume: what should I do to raise the free system PTE and most important how could I lower the RPC latency? Any thoughts?

You've missed the most important part. Physical disks. number and RAID configuration. Tell us the number and speed of the disks that are assigned to logs. Tell us the RAID types of those. Repeat for stores.

Hi, I also suggest you read following two articles regarding the Exchange performance issue: Troubleshooting Microsoft Exchange Server Performance http://technet.microsoft.com/en-us/library/aa997270(EXCHG.65).aspx Exchange Server 2003 Performance: Ten Things to Think About http://technet.microsoft.com/en-us/library/aa996023.aspx Mike Shen TechNet Subscriber Support in forum If you have any feedback on our support, please contact EMAIL REMOVED

Thank you for both replies. I didn't really look into the disks but I think you are both right and as the number one from Mike's top 10 says: When it comes to Exchange performance, storage isn’t just your friend, it’s your best friend. Your storage solution can make or break performance. In fact, the number one cause of RPC-related communication problems between Outlook and Exchange is storage latency.I wasn't aware of the fact that storage was the most common source of RPC related problems. I will look into it some more.