From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Mon, 11 Jun 2007 09:57:59 -0700 (PDT) From: Christoph Lameter Subject: Re: [PATCH 10 of 16] stop useless vm trashing while we wait the TIF_MEMDIE task to exit In-Reply-To: <20070611165032.GJ7443@v2.random> Message-ID: References: <24250f0be1aa26e5c6e3.1181332988@v2.random> <20070609015944.GL9380@v2.random> <20070609140552.GA7130@v2.random> <20070609143852.GB7130@v2.random> <20070611165032.GJ7443@v2.random> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org Return-Path: To: Andrea Arcangeli Cc: linux-mm@kvack.org List-ID: On Mon, 11 Jun 2007, Andrea Arcangeli wrote: > On Mon, Jun 11, 2007 at 09:07:59AM -0700, Christoph Lameter wrote: > > Filtering tasks is a very expensive operation on huge systems. We have had > > Come on, oom_kill.c only happens at oom time, after the huge complex > processing has figured out it's time to call into oom_kill.c, how can > you care about the performance of oom_kill.c? Apparently some folks > prefer to panic when oom triggers go figure... Its pretty bad if a large system sits for hours just because it cannot finish its OOM processing. We have reports of that taking 4 hours! > In turn killing the current task so that oom_kill.c is faster, is > quite a dubious argument. It avoids repeated scans over a super sized tasklist with heavy lock contention. 4 loops for every OOM kill! If a number of processes will be OOM killed then it will take hours to sort out the lock contention. Want this as a a SUSE bug? -- 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