From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Thu, 23 Aug 2001 08:24:45 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Thu, 23 Aug 2001 08:24:36 -0400 Received: from ns.ithnet.com ([217.64.64.10]:25609 "HELO heather.ithnet.com") by vger.kernel.org with SMTP id ; Thu, 23 Aug 2001 08:24:22 -0400 Date: Thu, 23 Aug 2001 14:24:07 +0200 From: Stephan von Krawczynski To: Marc Heckmann Cc: linux-kernel Subject: Re: small patch for 2.4.9 VM Message-Id: <20010823142407.54c332e9.skraw@ithnet.com> In-Reply-To: <20010823072104.A13430@hbe.ca> In-Reply-To: <20010823072104.A13430@hbe.ca> Organization: ith Kommunikationstechnik GmbH X-Mailer: Sylpheed version 0.5.3 (GTK+ 1.2.10; i686-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 23 Aug 2001 07:21:04 -0400 Marc Heckmann wrote: > [not on list, please CC me] > > Hi, > > I've been tracking the vm changes in the 2.4.9-pre series. I was seeing > really good improvements with 2.4.9-pre3 but then in pre4 it went to shit > on my box (192mb, 200mb swap). The page cache was huge at all times and > went pretty deep into swap on light loads. staring at the diff between > pre3 and pre4, I noticed that background page aging in kswapd has changed > [see do_try_free_pages], instead of just doing refill_inactive_scan(), it > now does swap_out() first, then refill_inactive. Somehow, this seems to > prevent proper page aging or something [please correct me if i'm wrong, > haven't had the time to stare at swap_out() yet]. Anyway the short patch > below, makes it behave like pre3 which is quite good for me. This might > also be the cause of other peoples mm problems with 2.4.9 final. Sorry it isn't. I tested it and it has exactly the same problem under 2.4.9 with this patch than the straight kernel. Interestingly the error message from alloc_pages does not come up, but NFS-copy fails anyway when all the physical mem is eaten up by caches. meminfo in failing state: total: used: free: shared: buffers: cached: Mem: 921726976 918994944 2732032 0 6815744 823762944 Swap: 271392768 0 271392768 MemTotal: 900124 kB MemFree: 2668 kB MemShared: 0 kB Buffers: 6656 kB Cached: 804456 kB SwapCached: 0 kB Active: 276020 kB Inact_dirty: 528988 kB Inact_clean: 6104 kB Inact_target: 6628 kB HighTotal: 0 kB HighFree: 0 kB LowTotal: 900124 kB LowFree: 2668 kB SwapTotal: 265032 kB SwapFree: 265032 kB Good about it: it does not swap. Bad: it does not work either. Forget this patch. Regards, Stephan