Gus Correa wrote: > Hi Ralph > > Ralph Castain wrote: >> One possibility is that the sm btl might not like that you have >> hyperthreading enabled. > > I remember that hyperthreading was discussed months ago, > in the previous incarnation of this problem/thread/discussion on > "Nehalem vs. Open MPI". > (It sounds like one of those supreme court cases ... ) > > I don't really administer that machine, > or any machine with hyperthreading, > so I am not much familiar to the HT nitty-gritty. > How do I turn off hyperthreading? > Is it a BIOS or a Linux thing? > I may try that. >
HyperThreading can easily be turned off in the BIOS. At the risk of starting a long off-topic discussion, I'm not sure HT is really needed on non-Windows systems. I heard Intel added it to their processors to get around deficiencies of the scheduler in Windows. I'm not a hardware/operating system expert, so I'd google for more definitive information. Or wait for someone else from this list to reply. -- Prentice
