JSI Tip 9175. The processor load is NOT distributed across multiple processors on your multi-processor server?

Jerold Schulman

March 21, 2005

1 Min Read
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You notice that one processor is used much more often that the other processor(s).

If your network is very busy. your Windows clients may receive one of the following errors when attempting to connect to the server:

System error 64 has occurred. The specified network name is no longer available.

System error 121. The semaphore timeout period has expired.

System Error 240 has occurred, the session was canceled.

This behavior will occur if the ProcessorAffinityMask Value Name, a REG_DWORD data type, at HKEY_LOCAL_MACHINESystemCurrentControlSetServicesNDISParameters is NOT set to 0xFFFFFFFE.

NOTE: The ProcessorAffinityMask Value Name specifies which processors can service DPCs (Delayed Procedure Calls) for network network adapters. Each bit represents a processor, with the low bit being processor 0. A data value of 0x0 or 0xFFFFFFFF disables the ProcessorAffinityMask function.

NOTE: You can use REG.EXE built into Windows Server 2003 and later, built into Windows XP, or installed from the Windows 2000 Support Tools on the operating system CD-ROM, to set the value remotely:

REG ADD \ServerNameHKLMSystemCurrentControlSetServicesNDISParameters /V ProcessorAffinityMask /T REG_DWORD /F /D 0xFFFFFFFE



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