On Mon, Feb 21, 2005 at 12:12:51AM +0100, Daniel Egger <[EMAIL PROTECTED]> 
> >Linux will not keep two threads running on a single cpu if both are 
> >ready
> >and nothing else is running, regardless of locality etc., as the kernel
> >lacks the tools to effectively decide wether threads should stay on a 
> >cpu
> >or not.
> Yes and no. I just figured out that the tools I were
> looking for are called schedutils and can be used to
> change the affinity settings of a process, i.e. pin
> it to some CPU or allow it to migrate as the kernel
> decides between a set of CPUs.

I should have said "unless specially instructed to do so", i.e., not by

> Forcing the NPTL implementation to degrade to legacy

BTW, is this 2.4 or 2.6?

> I can force it to use both CPUs now, but even with
> 200% utilization it is 2s slower to run this stupid
> ubenchmark than on 1 CPU without threads.

Now, that's definitely a result then :)

                The choice of a
      -----==-     _GNU_
      ----==-- _       generation     Marc Lehmann
      ---==---(_)__  __ ____  __      [EMAIL PROTECTED]
      --==---/ / _ \/ // /\ \/ /      http://schmorp.de/
      -=====/_/_//_/\_,_/ /_/\_\      XX11-RIPE
Gimp-developer mailing list

Reply via email to