lkml.org 
[lkml]   [2008]   [May]   [9]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
FromIngo Oeser <>
SubjectRe: Restricting Processor Usage
DateFri, 9 May 2008 21:28:56 +0200
Hi Brian
On Friday 09 May 2008, you wrote:
> Now that I've got sched_(set|get)affinity working (thank you all for all of
> the great help), I need to figure out how to unload the processors in the
> machine.

excerpt from Documentation/kernel-parameters.txt:

isolcpus= [KNL,SMP] Isolate CPUs from the general scheduler.
Format:
<cpu number>,...,<cpu number>
or
<cpu number>-<cpu number> (must be a positive range in ascending order)
or a mixture
<cpu number>,...,<cpu number>-<cpu number>
This option can be used to specify one or more CPUs
to isolate from the general SMP balancing and scheduling
algorithms. The only way to move a process onto or off
an "isolated" CPU is via the CPU affinity syscalls.
<cpu number> begins at 0 and the maximum value is
"number of CPUs in system - 1".

This option is the preferred way to isolate CPUs. The
alternative -- manually setting the CPU mask of all
tasks in the system -- can cause problems and
suboptimal load balancer performance.

And then use sched_set_affinity to fill your CPUs.

Happy imaging :-)


Best Regards

Ingo Oeser


\
 
 \ /
  Last update: 2008-05-09 21:27    [from the cache]
©2003-2010