Re: [PATCH] Yielding processor resources during lock contention

[Nick Piggin]

Zwane Mwaikambo wrote:
> On Sun, 12 Sep 2004, Nick Piggin wrote:

> > I presume the hypervisor switch much incur the same sorts of costs as
> > a context switch?
>
>
> In the PPC64 and P4/HT case the spinning on a lock is a bad utilisation of 
> the execution resources and that's what we're really trying to avoid, not 
> necessarily cache thrashing from a context switch.

But isn't yielding to the hypervisor and thus causing it to schedule
something else basically the same as a context switch? (I don't know
anything about POWER).

If yes, then shouldn't your lock be a blocking lock anyway?
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