Re: [patch] sched_[set|get]_affinity() syscall, 2.4.15-pre9

[Andi Kleen]

Joe Korty <[e-mail]> writes:
> 
> I have not yet seen the patch, but one nice feature that a system call 
> interface
> could provide is the ability to *atomically* change the cpu affinities of 
> sets of
> processes

Could you quickly explain an use case where it makes a difference if 
CPU affinity settings for multiple processes are done atomically or not ? 

The only way to make CPU affinity settings of processes really atomically 
without a "consolidation window" is to
do them before the process starts up. This is easy when they're inherited --
just set them for the parent before starting the other processes. This 
works with any interface; proc based or not as long as it inherits.

-Andi