i m working on Asp.net & C# project which requires output with high performance & speed [ (i.e we want an our system to perform 2000 queries in 30ms , for which we are using 2 Gb RAM , Xenon 2.5 GHz GHz Dual core Processor , Windows server 2003 as OS (plus all latest configurations available for speeding a process ) ]. but we are facing a very strange problem . when we perform load test on SINGLE xenon processor , we get output in 900 ms ,but when we use Dual processor , we get out put in more time ,but in actual cae it should happened be reverse ,(i.e. it should take less time since we r using Dual core Xenon processor), so can u plz tell me ,what could be the possible cause of this problem ,is there any need to do some performance tuning in WINDOWS SERVER 2003 ? if so then what??? thnks in advance Sachin

Well, for starters, have you enabled the /3GB switch? It doesn't have to do with dual procs, but it should help. "Republicans in Congress are moving to ratify a constitutional amendment to ban flag burning, thus ending the Iraq insurgency."

He only has 2gig of ram so the /3gb or /pae switches don't come into play until over 4gig of ram. You have encountered a common misconception of dual processing. Your application clearly is single processor not smp enabled. It takes different programming to program a app to do symentric multiprocessing which is how you get it to use both processors.

/3GB switch is recommended by Microsoft when you have over a gig of memory for Exchange for example. However, the application must support it in order for it to do anything. "the /3gb or /pae switches don't come into play until over 4gig of ram." If that's true, why does Microsoft support it in Windows 2003 Standard Edition considering Std. Edition only supports 4GB. "Republicans in Congress are moving to ratify a constitutional amendment to ban flag burning, thus ending the Iraq insurgency."

"The PAE mode kernel requires an Intel Architecture processor, Pentium Pro or later, more than 4 GB of RAM, and Windows 2000, Windows XP, or Windows Server 2003" quoted from http://www.microsoft.com/whdc/system/platform/server/PAE/PAEdrv.mspx All 32 bit OS's only support 4gig. Standard mainboards only support 4gig ram. BUT there are boards that support more phyical ram. This is where the /pae switch comes in. according to this "The /3GB switch should not be used on Windows 2000 Server or Windows Server 2003 Standard Edition because it is unsupported and can cause application or operating system crashes" server03 std does NOT support the /3gb switch see here http://www.microsoft.com/technet/prodtechnol/exchange/guides/E2k3Perf_ScalGuide/e834e9c7-708c-43bf-b877-e14ae443ecbf.mspx This http://www.microsoft.com/whdc/system/platform/server/PAE/PAEmem.mspx explains why you would use the /3gb switch which fundimentally changes the ratio of 4gig split in two for apps and kernal. The /3gb alters this ratio but really is only effective if you have more than 4gig of physical ram. these switches were created to utilize physical memory beyond 4gig until 64bit was on the market with has a higher address range HTH

"This is where the /pae switch comes in." Never debated that switch... "server03 std does NOT support the /3gb switch" Not true... Microsoft recommends for example Exchange 2003 running on a 2003 server, both Standard and Enterprise, use the /3gb switch no matter what! "When you install Exchange Server 2003 on a Microsoft Windows Server 2003-based computer that has 1 gigabyte (GB) or more of physical random access memory (RAM) installed, and that is home to mailboxes or public folders, you *must* edit the Boot.ini file to optimize the virtual memory usage of the Information Store service." http://support.microsoft.com/?kbid=823440 That article you linked to is out of date concerning the /3gb switch. "The /3gb alters this ratio but really is only effective if you have more than 4gig of physical ram." Then why does Microsoft recommend to do it on Exchange servers with 1GB of RAM or more? http://go.microsoft.com/fwlink/?linkid=3052&kbid=266096 http://support.microsoft.com/?kbid=823440 I'll tell you why. It improves performance and corrects memory fragmentation problems. That comes from supporting Exchange for Microsoft. It's been recommended since Exchange 5.5! What can it be enabled on? NT4 Enterprise Windows 2000 Advanced Server and above Windows XP Pro (Microsoft may not provide technical assistance for problems if it's being used) Windows 2003 Standard (MS will provide technical assistance if the app vendor supports its use) Windows 2003 Enterprise and above "these switches were created to utilize physical memory beyond 4gig until 64bit was on the market with has a higher address range" Dude, that switch was around in the NT4 days. It was most certainly NOT designed just for 4GB+ of memory! It can even be used in WinXP Pro! "Republicans in Congress are moving to ratify a constitutional amendment to ban flag burning, thus ending the Iraq insurgency."

So what is the auguement about heropsycho? I don't believe the quote from Microsoft's Exchange Tech Center is outdated with a 2005 copyright statement at the bottom. Your referance relates to 2000/3 enterprise and standard. It would appear it contradicts the warning in the document I referanced. I will bring that to the attention of MS since I am a MVP. Thanks for the heads up. Been around since NT days. Well sure the /3gb has been since then just as it states it came with the advent of the pentium pro. Do you remember the Merced Chip? That 64bit vaporware that was being talked about in NT's hayday? Other sources I have read stated these two switches came about because of 64bit research and the fact the newer chipsets could address more physical memory then the OS could. So what is yankin your chain about this? I gave you my referances and even quoted from Microsoft's site with states you want more memory Quite honestly this has nothing to do with the original post nor does it address the issue of a single processor app running on a smp system. The /pae and /3gb have NOTHING to do with this. If you take a moment to think about /3GB and that the poster only has 2gigs of ram, how, even with EXCHANGE, would it make a difference? With it you have 1gig and 1gig, without it you have 1gig and 1gig. Its a moot point. So what are you arguing about?