/fastdetect /NoExecute=OptOut

[19902003]

HI,
My ex 2003 has the "/fastdetect /NoExecute=OptOut" in boot.ini, I want to have better performance, so I went ahead add the "3GB /Userva=3030" switch after /fastdetec, but the article didn't tell me whether I need to remove "NoExecute=OptOut" or not. if I remove it, am I going to experience any issues.

Thank you,

 

[jerake75]

I just did exactly what you described (take out NoExecute=OptOut, added /3GB /USERVA=3030 after /fastdetect); I had no ill effects, running Windows 2003 Server Standard with Exchange 2003 Server Enterprise SP1.

I also tried it without removing the NoExecute; I had the MSExchangeSA service fail on startup as a result.

TMH

 

[xmsre]

Short answer: Put the /NoExecute=optout back in.

Long answer:

Taking out the NoExecute means that the PAE Kernal is loaded.

http://support.microsoft.com/kb/875352/en-us

That's begging for problems. Exchange does not support the PAE extentions and cannot effectively use memory over 4GB.

http://support.microsoft.com/kb/815372/

In fact, loading the PAE kernel causes each PTE to consume twice as much RAM (two PTEs per buffer), effectively halving the number of available PTEs.

http://support.microsoft.com/kb/291988/en-us

http://support.microsoft.com/kb/311901/en-us

If your free system PTEs fall below 7000, your system may become unstable. You can monitor the PTE consumption by using Performance Monitor. The object to monitor is Free System Page Table Entries.

http://support.microsoft.com/kb/823440/en-us

 

[19902003]

3GB is not set, i have 2gb Ram on my exchanger server, it says if I set it to 3GB then I can get more performance. I am confuse. By Default, DEP is turn on that is why "/NoExecute=optout " is there.
Thanks,

 

[xmsre]

The /3GB switch increases your VM block size and reduces overall VM fragmentation so you do want it if you have over 1GB of RAM. If you use the /3GB switch, do use /Userva=3030 or /Userva=2970 which will pull 42m or 40m back for extra PTEs.


Don't forget to add heapdecommitfreeblockthreshold with a value of 0x40000 to the registry.

 

[19902003]

I have added both switches, but "heapdecommitfreeblockthreshold" was already in the registry and the value is set to "0x00000000 (0)

any thoughts?

Thanks,

 

[xmsre]

set it to 40000 hex. This tells the memory manager to hold up a bit before deallocating. The thought is that block will coelesce and result in less overall VM fragmentation.

http://support.microsoft.com/kb/315407/en-us