Thread: Daily Update.
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Unread 07-29-2003, 12:40 PM   #72
Cova
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Join Date: May 2002
Location: Canada
Posts: 247
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Just curious about that post you made up a bunch there jaydee - has anyone actually done any research into whether running one or two instances is faster on a HT processor? Just watching CPU useage is meaningless in this instance as no version of windows (except 2003 I hear but I haven't verified it yet) can tell the difference between a real second CPU and a virtual cpu created by HT. Because a second virtual HT cpu still has to share execution pipes inside the only real physical CPU, if the first instance is already using near all of those pipes the CPU is actually running at 100% load (and the virtual CPU is doing nothing, so windows reports 50% load), and adding a second instance will just make the CPU switch tasks around more often, incur more overhead, and slow down the entire process.
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