Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S269066AbUIHTwH (ORCPT ); Wed, 8 Sep 2004 15:52:07 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S268686AbUIHTuj (ORCPT ); Wed, 8 Sep 2004 15:50:39 -0400 Received: from omx3-ext.sgi.com ([192.48.171.20]:57005 "EHLO omx3.sgi.com") by vger.kernel.org with ESMTP id S269066AbUIHTuA (ORCPT ); Wed, 8 Sep 2004 15:50:00 -0400 Message-ID: <413F6362.6000001@sgi.com> Date: Wed, 08 Sep 2004 14:54:10 -0500 From: Ray Bryant User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.4) Gecko/20030624 Netscape/7.1 X-Accept-Language: en-us, en MIME-Version: 1.0 To: "Martin J. Bligh" CC: Marcelo Tosatti , Con Kolivas , Andrew Morton , linux-kernel@vger.kernel.org, linux-mm@kvack.org, riel@redhat.com, piggin@cyberone.com.au Subject: Re: swapping and the value of /proc/sys/vm/swappiness References: <413CB661.6030303@sgi.com> <20040906162740.54a5d6c9.akpm@osdl.org> <20040907000304.GA8083@logos.cnet> <20040907212051.GC3492@logos.cnet> <413F1518.7050608@sgi.com> <5860000.1094664673@flay> In-Reply-To: <5860000.1094664673@flay> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1682 Lines: 47 Martin J. Bligh wrote: >>It seems to me that the 5% number in there is more or less arbitrary. >>If we are on a big memory Altix (4 TB), 5% of memory would be 200 GB. >>That is a lot of page cache. > > > For HPC, maybe. For a fileserver, it might be far too little. That's the > trouble ... it's all dependant on the workload. Personally, I'd prefer > to get rid of manual tweakables (which are a pain in the ass in the field > anyway), and try to have the kernel react to what the customer is doing. > I guess we can leave them there for overrides, but a self-tunable default > would be most desirable. > I agree that tunables are a pain in the butt, but a quick fix would to be at least to add that 5% to the set of stuff settable in /proc/sys/vm. Most workloads/systems won't need to change it. Very large Altix systems could change it if needed. I don't think that is at the root of the swappiness problems with 2.6.9-rc1-mm3, though. > For instance, would be nice if we started doing writeback to the spindles > that weren't busy much earlier than if the disks were thrashing. > > M. > > -- Best Regards, Ray ----------------------------------------------- Ray Bryant 512-453-9679 (work) 512-507-7807 (cell) raybry@sgi.com raybry@austin.rr.com The box said: "Requires Windows 98 or better", so I installed Linux. ----------------------------------------------- - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/