From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <416E2B6F.5040803@yahoo.com.au> Date: Thu, 14 Oct 2004 17:31:59 +1000 From: Nick Piggin MIME-Version: 1.0 Subject: Re: Page cache write performance issue References: <20041013054452.GB1618@frodo> <20041012231945.2aff9a00.akpm@osdl.org> <20041013063955.GA2079@frodo> <20041013000206.680132ad.akpm@osdl.org> <20041013172352.B4917536@wobbly.melbourne.sgi.com> <416CE423.3000607@cyberone.com.au> <20041013013941.49693816.akpm@osdl.org> <20041014005300.GA716@frodo> <20041013202041.2e7066af.akpm@osdl.org> <20041014071659.GB1768@frodo> In-Reply-To: <20041014071659.GB1768@frodo> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: Nathan Scott Cc: Andrew Morton , piggin@cyberone.com.au, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-xfs@oss.sgi.com List-ID: Nathan Scott wrote: > On Wed, Oct 13, 2004 at 08:20:41PM -0700, Andrew Morton wrote: > >>Nathan Scott wrote: >> >>> I just tried switching CONFIG_HIGHMEM off, and so running the >>> machine with 512MB; then adjusted the test to write 256M into >>> the page cache, again in 1K sequential chunks. A similar mis- >>> behaviour happens, though the numbers are slightly better (up >>> from ~4 to ~6.5MB/sec). Both ext2 and xfs see this. When I >>> drop the file size down to 128M with this kernel, I see good >>> results again (as we'd expect). >> >>No such problem here, with >> >> dd if=/dev/zero of=x bs=1k count=128k >> >>on a 256MB machine. xfs and ext2. > > > Yup, rebooted with mem=128M and on my box, & that crawls. > Maybe its just this old hunk 'o junk, I suppose; odd that > 2.6.8 was OK with this though. > Just out of interest, can you get profiles and a few lines of vmstat 1 from 2.6.8 and 2.6.9-rc, please? -- 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: aart@kvack.org