From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx151.postini.com [74.125.245.151]) by kanga.kvack.org (Postfix) with SMTP id 242236B0034 for ; Thu, 6 Jun 2013 10:15:32 -0400 (EDT) Date: Thu, 6 Jun 2013 14:15:29 +0000 From: Christoph Lameter Subject: Re: [PATCH 1/7] mm: remove ZONE_RECLAIM_LOCKED In-Reply-To: <51AFA786.1040608@gmail.com> Message-ID: <0000013f19d7a21d-0bc478a9-c65b-4d66-a774-266b17bcde2a-000000@email.amazonses.com> References: <1370445037-24144-1-git-send-email-aarcange@redhat.com> <1370445037-24144-2-git-send-email-aarcange@redhat.com> <51AFA185.9000909@gmail.com> <0000013f161c3f42-14ae4d9d-fd85-47dd-ba80-896e1e84a6fe-000000@email.amazonses.com> <51AFA786.1040608@gmail.com> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org List-ID: To: KOSAKI Motohiro Cc: Andrea Arcangeli , linux-mm@kvack.org, Mel Gorman , Rik van Riel , Hugh Dickins , Richard Davies , Shaohua Li , Rafael Aquini On Wed, 5 Jun 2013, KOSAKI Motohiro wrote: > > There was early on an issue with multiple zone reclaims from > > different processors causing an extreme slowdown and the system would go > > OOM. The flag was used to enforce that only a single zone reclaim pass was > > occurring at one time on a zone. This minimized contention and avoided > > the failure. > > OK. I've convinced now we can removed because sc->nr_to_reclaim protect us > form > this issue. How does nr_to_reclaim limit the concurrency of zone reclaim? What happens if multiple processes are allocating from the same zone and they all go into direct reclaim and therefore hit zone reclaim? -- 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/ . Don't email: email@kvack.org