Re: Mersenne: 50% CPU?

[Shane Sanford]

I have a Pentium 4 processor and TM indicates an average usage of close to 100% CPU for Prime 95 - am I running 'multiple instances' without being aware of it? If so, how do I prevent this if it will degrade efficiency?   Not all P4's have hyper threading & not all motherboards support it on top of that.  So it requires a HT enabled CPU, HT enabled Motherboard, & HT supported OS for HT to function.  From my experience HT is a nice feature since it gives Prime95 a chance to run even when other "not nice" programs are running that don't release the processor as often as they should even if it's not busy.  The down side is with HT enabled Prime95 is more likely to interfere with certain performance sensitive applications.    If you want to learn more about Prime95 & HT there has been several recent posts on the topic at   http://www.mersenneforum.org/forumdisplay.php?s=&forumid=9   There is some evidence that running a LL (high usage of SSE2 floating point calculations) & TF (high usage of SSE2 integer calculations) may increase overall throughput.   Shane