From mboxrd@z Thu Jan 1 00:00:00 1970 Subject: Re: [patch 17/20] non-reclaimable mlocked pages From: Lee Schermerhorn In-Reply-To: <20071219095307.683978b0@cuia.boston.redhat.com> References: <20071218211539.250334036@redhat.com> <20071218211550.186819416@redhat.com> <200712191156.48507.nickpiggin@yahoo.com.au> <20071219084534.4fee8718@bree.surriel.com> <1198074247.6484.17.camel@twins> <20071219095307.683978b0@cuia.boston.redhat.com> Content-Type: text/plain Date: Wed, 19 Dec 2007 11:08:38 -0500 Message-Id: <1198080519.5333.28.camel@localhost> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: Rik van Riel Cc: Peter Zijlstra , Nick Piggin , linux-mm@kvack.org, linux-kernel@vger.kernel.org List-ID: On Wed, 2007-12-19 at 09:53 -0500, Rik van Riel wrote: > On Wed, 19 Dec 2007 15:24:07 +0100 > Peter Zijlstra wrote: > > > I thought Lee had patches that moved pages with long rmap chains (both > > anon and file) out onto the non-reclaim list, for those a slow > > background scan does make sense. > > I suspect we won't be needing that code. The SEQ replacement for > swap backed pages might reduce the number of pages that need to > be scanned to a reasonable number. > > Remember, steady states are not a big problem with the current VM. > It's the sudden burst of scanning that happens when the VM decides > that it should start swapping (and every anonymous page is referenced) > that kills large systems. Yes, I still have the patch [for long anon_vma lists--not for excessively mapped file, yet] and I'm keeping it up to date and tested. I do see softlockups on the anon_vma and i_mmap_locks under stress, even with the reader/writer lock patches. I'll be trying the workloads on Rik's latest patches to see if they address these lockups. Lee -- 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