Re: [RT LATENCY] 249 microsecond latency caused by slub'sunfreeze_partials() code.

From: Joonsoo Kim
Date: Tue Mar 26 2013 - 22:59:15 EST


On Mon, Mar 25, 2013 at 02:32:35PM -0400, Steven Rostedt wrote:
> On Mon, 2013-03-25 at 18:27 +0000, Christoph Lameter wrote:
> > On Mon, 25 Mar 2013, Steven Rostedt wrote:
> >
> > > If this makes it more deterministic, and lower worse case latencies,
> > > then it's definitely worth the price.
> >
> > Yes that would make it more deterministic. Maybe I should add an option
> > to be able to compile the allocator without cpu partial page support?
>
> I agree that would be useful.

Hello, Steven and Christoph.

How about using spin_try_lock() in unfreeze_partials() and
using spin_lock_contented() in get_partial_node() to reduce latency?
IMHO, this doesn't make code more deterministic, but can maintain
a benefit of cpu partial page with tolerable latency.

Thanks.

>
> -- Steve
>
>
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