Re: program runs almost twice as slow on 2 CPU machine when 1 CPU is u


"JC" <JC@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote in message
news:908DDF92-9794-4768-900B-777ADC05B83C@xxxxxxxxxxxxxxxx
I have a 2 CPU WinXP pro. If my CPU intensitve program runs while there
is
already another CPU intensive program running, I find that this program
runs
almost twice as slow when there is no other program running.

In general, I found that when one CPU is being used, the program runs
20-30%
slower compared when one of the CPU is idle.

No, the program is not I/O intenstive.

What's wrong here? Any system property that I can set to change this?

Thanks a lot.

Why do you think that something is "wrong"? It sounds like things are
working the way they are supposed to: if yours is the only CPU intensive app
that's currently executing, then it gets all of both CPUs and runs fast,
whereas if it's not, then it must share CPU with other apps and it runs more
slowly.

Note: Your app might be designed to use only one CPU at a time, but other
apps might be designed to use as many CPUs are available (which is good).


.

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