Matthias Waldhauer wrote: > <[EMAIL PROTECTED]> > Subject: Re: Mersenne: 50% CPU? > > Quantum Mechanic wrote: > > I have an Intel 4 box from MDG, 1 CPU, 2.4GHz, > 512MB > > RAM, L1 8KB, L2 512KB. > > > > Prime95 is only getting 50%, with System Idle > Process > > taking 50%. > > > > It's currently running an LL test in the 20M > range. > > > > Any ideas why it's only 50%? > > I think, there are 2 processes running as idle task > (one of them is > Prime95). And I assume that both have the same > priority setting, so the > OS "thinks", they are equally important (same > priority) and gives > exactly half of the available time to each of them > because > Hyperthreading suggests, that there are enough real > CPUs to do so > (although there aren't). > > Try increasing Prime95's priority setting.
I turned off Hyperthreading, and I get 99% of the CPU on Prime95, with the same iteration times as before. So it's just an accounting trick. [I wonder if Enron knows about this?] -QM ===== ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Quantum Mechanics: The dreams stuff is made of __________________________________ Do you Yahoo!? Protect your identity with Yahoo! Mail AddressGuard http://antispam.yahoo.com/whatsnewfree _________________________________________________________________________ Unsubscribe & list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
