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Best of Q&A from Webcast: Exchange Server 2003 Performance Tuning

Your BossHi!

Below I’ve pasted an edited and cleaned up copy of most of the Q&A from today’s webcast on Exchange Server 2003 Performance Tuning

BIG thank you to John “no, I’m from GREAT Britain” Baker for handling the Q&A on the backend, and who’s work this really represents.


Questions and Answers:

“Will the expta be covered in this session?”

The Performance Tuning Analyzer?  Not today, no. That was discussed (briefly, though not demonstrated) in a session I did last week on Exchange Tips, Tricks, and Shortcuts.

“You keep cutting in and out and I can’t hear anything. Is there a number to dial into this conference?”

Sorry about that.  Yes, there is always a number you can ask for.  Between you and me, I sincerely with the LiveMeeting folks would get that audio problem figured out. 

And I’m told that sometimes the audio delay is around 10 seconds.  Any delay greater than a second or two is just unacceptable.  My $0.02.

“Can the tools be used for Exchange 2000?”

There are Exchange 2000 versions of the tools.

“What is the difference between LoadSim and ESP?”

ESP simulates large numbers of client sessions by concurrently accessing one or more protocol servers.  Loadsim simulates the performance load of MAPI clients with this benchmarking tool, which allows you to test how a server running Exchange 2003 responds to e-mail loads.

“Would you use Jetstress or loadsim in a production environment (after hours of course…)”

Neither.  They should only be used in test/lab environments

“If you are running Windows 2003 Server, can Exchange 2003 benefit from 4 gigs of memory?”

Yes.  (referenced later when discussing the /4GB and the /USERVA  switches)

“Will you be covering the Exchange Server Performance Troubleshooting Analyzer? Is that a good tool to get a quick overview of how well a server is handling the load?”

No, we didn’t cover it in this session – and yes, that’s exactly what it does.  It programmatically collects configuration data, performance counters and live tracing information from an Exchange server.  The tool analyzes each subsystem to determine individual bottlenecks, and then aggregates the information to provide root cause analysis.

“SBS2003 installs SQL, ISA, Sharepoint, and Exchange 2003 on the same server and the license does not allow relocating the applications to other machines. With 10 users the Exchange Best Practice Analyzer recommends setting the 3GB switch. I feel like my system is running fine without it and it might have adverse side effects since I have all the standard SBS applications plus CRM and LCS on the same box. Do I need to use the 3G switch if I have 4G of RAM?”

You don’t need to use it, if you’re happy with the current performance then you’re fine.  However, it’s not just Exchange that benefits.  /3GB reserves more user virtual memory for ALL user mode applications.  However – you need to be careful, and KNOW the applications you’re running will support this well. (Example: Many people think “Cool, I’ll make my Virtual Server machines run better because they’ll have more memory.”  But in truth, Virtual Server uses a lot of Kernel memory also, which is lost when you use that switch.  So.. be careful. J (See “the Virtual PC Guy”s WebLog for this info.)

“What is the best way to find out if a PRODUCTION server can handle more users? (just pile on users until you see smoke?;-)”

Test in a lab environment with a similar server, or as close as possible, using the tools discussed. If the server is in production that’s a little late in the game for doing sizing.

There you should look at using the ExPTA: http://www.microsoft.com/downloads/details.aspx?familyid=4BDC1D6B-DE34-4F1C-AEBA-FED1256CAF9A&displaylang=en

“Can the /3GB switch be used on servers running SBS 2003?”

Yes it can.

“Best Practice Analyzing Tool recommends to set also the /3GB at the GC what’s the impact on exchange?”

It could, probably will, affect performance.

“FYI, http://support.microsoft.com/kb/815372 is the ultimate article which covers all the 2003 server settings Kevin just went through”

Yes, thanks…. http://support.microsoft.com/kb/815372

“Should /3GB switch be used if i have 2 GB of memory in the server?”

Yes.  It’s all a matter of how the server allocates the 4 GB of virtual memory space – whether or not the machine physically has 4GB.   The recommendation is to use /3GB if you have 1GB or more of physical memory.

“Is the ‘/nopae’ switch a useful switch when optimizing the server? (Per KB827281)”

It’s recommended that you disable PAE mode only to work around a hardware issue or to troubleshoot a specific issue that involves PAE or Address Windowing Extensions (AWE).

“Will an offline copy of this presentation be made available?  Can I have the URL for it?”

It will be available in 24 hours at www.microsoft.com/webcasts in the on demand section

“Does Exchange 2k3 Standard Edition allow you create multiple storage groups?”

One Storage group in Standard.

“I have read that WINS is suggested for large subnetted networks but it was not clear as to what issues are caused by not having WINS and only using DNS. Are issues seen on on the clients like outlook or only see on the server side in form of performance issues?”

Where did you read that?


In mixed enviroments it is used and helps.  Check http://support.microsoft.com/Default.aspx?id=837391

“The following Exchange functionality still depends on WINS name resolution: • The Exchange Server 2003 Setup program and the Exchange 2000 Server Setup program, especially on clustered servers. • Exchange Mailbox Merge Wizard (ExMerge) on an Exchange 2003 computer and on an Exchange 2000 computer. • Changing a password for an Exchange 2003 mailbox or an Exchange 2000 mailbox through Microsoft Outlook Web Access (OWA). • Exchange System Manager on an Exchange 2003 computer and on an Exchange 2000 computer. Note Additionally, Microsoft Outlook clients that are earlier than Microsoft Office Outlook 2003 also require NetBIOS name resolution.”

“How do you determine that you should be indexing a particular schema attribute?”

Check this link http://www.microsoft.com/technet/prodtechnol/exchange/guides/E2k3Perf_ScalGuide/aacaf4d8-a0c1-42d0-8eda-1c410177a7ce.mspx?mfr=true

“Isn’t it better to set MinUserDC value to 1? This way as long as there is at least one DC available, Exchnage will not use PDCE?”

Check http://support.microsoft.com/default.aspx?scid=kb;EN-US;298879

“Is there any consideration when I use specific tips in a cluster environment?”

I’m sure there are, and the information is typically included with each article or chapter.

Here is my blog resource page for this session again: