From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <486327F9.6030004@ah.jp.nec.com> Date: Thu, 26 Jun 2008 14:24:09 +0900 From: Takenori Nagano MIME-Version: 1.0 Subject: Re: [RFC][PATCH] prevent incorrect oom under split_lru References: <20080624092824.4f0440ca@bree.surriel.com> <28c262360806242259k3ac308c4n7cee29b72456e95b@mail.gmail.com> <20080625150141.D845.KOSAKI.MOTOHIRO@jp.fujitsu.com> <28c262360806242356n3f7e02abwfee1f6acf0fd2c61@mail.gmail.com> <1214395885.15232.17.camel@twins> <28c262360806250605le31ba48ma8bb16f996783142@mail.gmail.com> <4862F5BB.9030200@ah.jp.nec.com> <28c262360806252137j78a90480n6c3973cd489c1ef2@mail.gmail.com> In-Reply-To: <28c262360806252137j78a90480n6c3973cd489c1ef2@mail.gmail.com> Content-Type: text/plain; charset=ISO-2022-JP Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: MinChan Kim Cc: Peter Zijlstra , KOSAKI Motohiro , Rik van Riel , linux-mm , LKML , Lee Schermerhorn , akpm@linux-foundation.org List-ID: MinChan Kim wrote: > On Thu, Jun 26, 2008 at 10:49 AM, Takenori Nagano > wrote: >> MinChan Kim wrote: >>> Hi peter, >>> >>> I agree with you. but if application's virtual address space is big, >>> we have a hard problem with mlockall since memory pressure might be a >>> big. >>> Of course, It will be a RT application design problem. >>> >>>> The much more important case is desktop usage - that is where we run non >>>> real-time code, but do expect 'low' latency due to user-interaction. >>>> >>>> >From hitting swap on my 512M laptop (rather frequent occurance) I know >>>> we can do better here,.. >>>> >>> Absolutely. It is another example. So, I suggest following patch. >>> It's based on idea of Takenori Nagano's memory reclaim more efficiently. >> Hi Kim-san, >> >> Thank you for agreeing with me. >> >> I have one question. >> My patch don't mind priority. Why do you need "priority == 0"? > > Hi, Takenori-san. > > Now, Kosaiki-san's patch didn't consider application latency. > That patch scan all lru[x] pages when memory pressure is very high. > (ie, priority == 0) > It will cause application latency to high as peter and me notice that. > We need a idea which prevent big scanning overhead > I modified your idea to prevent big scanning overhead only when memory > pressure is very big. Hi, Kim-san. Thank you for your explanation. I understand your opinion. But...your patch is not enough for me. :-( Our Xeon box has 128GB memory, application latency will be very large if priority goes to be zero. So, I would like to use "cut off" on every priority. I would like to delete "priority == 0", Can you? Thanks, Takenori -- 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