> On Saturday 15 March 2003 01:07, John R Pierce wrote: > > > > another minor question... Is there any way to force CPU affinity, or does > > mprime do that automatically? > > Unlike Windows, linux has a smart CPU/task allocation algorithm that tries > hard (but not too hard) to run a thread on the same CPU it used last. So > there's no need to force CPU affinity, in fact this might well damage > throughput.
actually, win2000/xp do the same. however, if I have two HT cpus appearing as 4 CPUs, and I'm running 2 copies of mprime, I would want to make sure they are running on CPU0 and CPU2 so that they don't both end up running on one HT cpu and competing for its FPU > As for hyperthreading - I believe the development kernel (2.5.x) has support > for hyperthreading. You will almost certainly need to build your own custom > kernel to obtain this support. redhat 8 seems to support it with the 2.4.18 kernel. The `noht` kernel parameter works to disable it. > The best sources of information on task allocation on a multiprocessor linux > system are, not surprisingly, the kernel documentation and the source code > itself. figgers. the rest of the documentation certainly sucks. _________________________________________________________________________ Unsubscribe & list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
