From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail202.messagelabs.com (mail202.messagelabs.com [216.82.254.227]) by kanga.kvack.org (Postfix) with SMTP id 920888D0040 for ; Tue, 29 Mar 2011 15:05:28 -0400 (EDT) Date: Tue, 29 Mar 2011 21:05:20 +0200 From: Andrea Arcangeli Subject: Re: [Lsf] [LSF][MM] page allocation & direct reclaim latency Message-ID: <20110329190520.GJ12265@random.random> References: <1301373398.2590.20.camel@mulgrave.site> <4D91FC2D.4090602@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4D91FC2D.4090602@redhat.com> Sender: owner-linux-mm@kvack.org List-ID: To: Rik van Riel Cc: lsf@lists.linux-foundation.org, linux-mm , Hugh Dickins Hi Rik, Hugh and everyone, On Tue, Mar 29, 2011 at 11:35:09AM -0400, Rik van Riel wrote: > On 03/29/2011 12:36 AM, James Bottomley wrote: > > Hi All, > > > > Since LSF is less than a week away, the programme committee put together > > a just in time preliminary agenda for LSF. As you can see there is > > still plenty of empty space, which you can make suggestions > > There have been a few patches upstream by people for who > page allocation latency is a concern. > > It may be worthwhile to have a short discussion on what > we can do to keep page allocation (and direct reclaim?) > latencies down to a minimum, reducing the slowdown that > direct reclaim introduces on some workloads. I don't see the patches you refer to, but checking schedule we've a slot with Mel&Minchan about "Reclaim, compaction and LRU ordering". Compaction only applies to high order allocations and it changes nothing to PAGE_SIZE allocations, but it surely has lower latency than the older lumpy reclaim logic so overall it should be a net improvement compared to what we had before. Should the latency issues be discussed in that track? The MM schedule has still a free slot 14-14:30 on Monday, I wonder if there's interest on a "NUMA automatic migration and scheduling awareness" topic or if it's still too vapourware for a real topic and we should keep it for offtrack discussions, and maybe we should reserve it for something more tangible with patches already floating around. Comments welcome. Thanks, Andrea -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org