Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Tue, 1 Oct 2002 13:10:40 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Tue, 1 Oct 2002 13:10:26 -0400 Received: from bitmover.com ([192.132.92.2]:31171 "EHLO mail.bitmover.com") by vger.kernel.org with ESMTP id ; Tue, 1 Oct 2002 13:10:15 -0400 Date: Tue, 1 Oct 2002 10:15:39 -0700 From: Larry McVoy To: Rik van Riel Cc: Daniel Phillips , Andrew Morton , Lorenzo Allegrucci , Linux Kernel Subject: Re: qsbench, interesting results Message-ID: <20021001101539.F5595@work.bitmover.com> Mail-Followup-To: Larry McVoy , Rik van Riel , Daniel Phillips , Andrew Morton , Lorenzo Allegrucci , Linux Kernel References: Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.2.5.1i In-Reply-To: ; from riel@conectiva.com.br on Tue, Oct 01, 2002 at 01:52:25PM -0300 X-MailScanner: Found to be clean Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1534 Lines: 30 On Tue, Oct 01, 2002 at 01:52:25PM -0300, Rik van Riel wrote: > On Tue, 1 Oct 2002, Daniel Phillips wrote: > > On Monday 30 September 2002 07:57, Andrew Morton wrote: > > > I'll take a look at some preferential throttling later on. But > > > I must say that I'm not hugely worried about performance regression > > > under wild swapstorms. The correct fix is to go buy some more > > > RAM, and the kernel should not be trying to cater for underprovisioned > > > machines if that affects the usual case. > > > > The operative phrase here is "if that affects the usual case". > > Actually, the quicksort bench is not that bad a model of a usual case, > > i.e., a working set 50% bigger than RAM. > > Having the working set of one process larger than RAM is > a highly unusual case ... "bk -r check -acv" on the linux-2.5 tree shows up as 39MB RSS in top and is actually much bigger, it wants all of the SCCS files in ram to go fast. If they are, it's about 15 seconds on a Ghz box, if they aren't, it's mucho longer. I _think_ we're careful to not go back and look at the same files twice but I might be smoking crack. All I know is that running a check on a 128MB machine is painful as hell. -- --- Larry McVoy lm at bitmover.com http://www.bitmover.com/lm - 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/