Re: How does 2.6 SMP scheduler assign runqueues to multi-cores?

[Nick Piggin]

On Thu, 2005-06-09 at 06:32 +0000, helen monte wrote:
> > > > > By the way, in an SMT/hyperthreading processor, does the latest 
> >kernel
> > > > > version assign one run queue per physical CPU, or per virtual 
> >processor?
> > > > >
> > > > one run-queue per physical CPU
> > >
> > > No. Each logical processor has its own runqueue.
> 
> How about muti-core?  Does each core also have its own run queue?  Does 
> anyone know how multi-core would work with SMT?  Is it possible that they 
> work together?  Is the following a possible scenario? :  A node has two 
> processors, each processor has two cores, and each core has two "virtual 
> cores". And there are 8 run queues in total.
> 

It is always one runqueue per virtual CPU, so dual core has 2 runqueues,
and dual core with SMT has 4 runqueues.

IBM and I believe Intel have chips that support SMT and have 2 cores.

-- 
SUSE Labs, Novell Inc.



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