[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date: Thu, 9 Sep 2010 09:32:52 -0500 (CDT)
From: Christoph Lameter <cl@...ux.com>
To: Mel Gorman <mel@....ul.ie>
cc: KOSAKI Motohiro <kosaki.motohiro@...fujitsu.com>,
Andrew Morton <akpm@...ux-foundation.org>,
Linux Kernel List <linux-kernel@...r.kernel.org>,
linux-mm@...ck.org, Rik van Riel <riel@...hat.com>,
Johannes Weiner <hannes@...xchg.org>,
Minchan Kim <minchan.kim@...il.com>,
KAMEZAWA Hiroyuki <kamezawa.hiroyu@...fujitsu.com>
Subject: Re: [PATCH 3/3] mm: page allocator: Drain per-cpu lists after direct
reclaim allocation fails
On Thu, 9 Sep 2010, Mel Gorman wrote:
> > This will have the effect of never sending IPIs for slab allocations since
> > they do not do allocations for orders > PAGE_ALLOC_COSTLY_ORDER.
> >
>
> The question is how severe is that? There is somewhat of an expectation
> that the lower orders free naturally so it the IPI justified? That said,
> our historical behaviour would have looked like
>
> if (!page && !drained && order) {
> drain_all_pages();
> draiained = true;
> goto retry;
> }
>
> Play it safe for now and go with that?
I am fine with no IPIs for order <= COSTLY. Just be aware that this is
a change that may have some side effects. Lets run some tests and see
how it affect the issues that we are seeing.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists