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Setting Processor Affinity in Win NT 4.0

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by jpeterson

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I know how to set processor affinity manually from Task Manager. Does anyone know if I can automate the process whenever I reboot the machine?

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by rightondudenospam!

You can permanently set processor affinity for a non-operating system executable, on both Windows 2000 and Windows NT 4.0, by using the Imagecfg.exe tool from the \support\debug\i386 folder of a Windows NT 4.0 CD-ROM

NOTE: Do NOT use imagecfg on any kernel operating system files.

To permanently set the processor affinity for your 32-bit executable, open a CMD prompt and type:

imagecfg -a 0xn \Path\yourprogram.exe

where 0xn is the affinity mask. The mask constrains your application to a specific CPU, from 0 - 31, where:

CPU MASK
0 0x1
1 0x2
2 0x4
3 0x8
4 0x10
5 0x20
6 0x40
7 0x80
8 0x100
etc
To set the affinity for "c:\util\Country Codes.exe" to processor 1, I typed:
imagecfg -a 0x2 "c:\util\Country Codes.exe"

and received the following response:

c:\util\Country Codes.exe contains no configuration information
c:\util\Country Codes.exe contains a Subsystem Version of 4.0
c:\util\Country Codes.exe updated with the following configuration information:
Process Affinity Mask: 00000002

When I launch Country Codes.exe, its' affinity is set to CPU 1.

by shanghai sam

Thanks very much for your answer. I was beginning to think there was no way of acheiving my goal. I use this machine to run Visual FoxPro, which, left to it's own devices, will hog as much of the processors' time as it can. By setting the affinity for VFP to the second processor, I can continue to use the machine for other work while VFP is toiling away.

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