Re: RT task scheduling

From: Ingo Molnar
Date: Sat Apr 08 2006 - 03:20:24 EST



* Bill Huey <billh@xxxxxxxxxxxxxxxxx> wrote:

> On Fri, Apr 07, 2006 at 07:56:20AM -0700, Darren Hart wrote:
> > The rt-overload mechanism is distinct from load balancing. RT overload
> > attempts to make sure the NR_CPUS highest priority runnable tasks are running
> > on each of the available CPUs. This isn't load balancing, this is "system
> > wide strict realtime priority scheduling" (SWSRPS). This scheduling should
> > take place even if there are 1000 non RT tasks on CPU 0 and none on all the
> > others. The load balancer would be responsible for distributing those 1000
> > non rt tasks to all the CPUs.
>
> I'm quite aware of what you're saying as well as a much of the
> contents of the -rt patch. Please don't assume that I'm not aware of
> this. The -rt patch doesn't do SWSRPS, [...]

to the contrary, the "RT overload" code in the -rt tree does strict,
system-wide RT priority scheduling. That's the whole point of it.

Ingo
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/