Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S264739AbUD3DU3 (ORCPT ); Thu, 29 Apr 2004 23:20:29 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S265048AbUD3DU3 (ORCPT ); Thu, 29 Apr 2004 23:20:29 -0400 Received: from c3p0.cc.swin.edu.au ([136.186.1.30]:59658 "EHLO swin.edu.au") by vger.kernel.org with ESMTP id S264739AbUD3DU1 (ORCPT ); Thu, 29 Apr 2004 23:20:27 -0400 Cc: Rik van Riel , Andrew Morton , Jeff Garzik , brettspamacct@fastclick.com, linux-kernel@vger.kernel.org From: Tim Connors Subject: Re: ~500 megs cached yet 2.6.5 goes into swap hell In-reply-to: <20040429141412.A12541@mail.kroptech.com> References: <20040428184008.226bd52d.akpm@osdl.org> <20040429141412.A12541@mail.kroptech.com> X-Face: "$j_Mi4]y1OBC/&z_^bNEN.b2?Nq4#6U/FiE}PPag?w3'vo79[]J_w+gQ7}d4emsX+`'Uh*.GPj}6jr\XLj|R^AI,5On^QZm2xlEnt4Xj]Ia">r37r<@S.qQKK;Y,oKBl<1.sP8r,umBRH';vjULF^fydLBbHJ"tP?/1@iDFsKkXRq`]Jl51PWN0D0%rty(`3Jx3nYg! Message-ID: Date: Fri, 30 Apr 2004 13:17:29 +1000 To: unlisted-recipients:; (no To-header on input) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2357 Lines: 51 Adam Kropelin said on Thu, 29 Apr 2004 14:14:13 -0400: > On Wed, Apr 28, 2004 at 09:47:45PM -0400, Rik van Riel wrote: > > On Wed, 28 Apr 2004, Andrew Morton wrote: > > > > > OK, so it takes four seconds to swap mozilla back in, and you noticed it. > > > > > > Did you notice that those three kernel builds you just did ran in twenty > > > seconds less time because they had more cache available? Nope. > > > > That's exactly why desktops should be optimised to give > > the best performance where the user notices it most... ... > The 'swappiness' tunable may well give enough control over the situation > to suit all sorts of users. If nothing else, this thread has raised > awareness that such a tunable exists and can be played with to influence > the kernel's decision-making. Distros, too, should give consideration to > appropriate default settings to serve their intended users. Actually, I decided to investigate how 2.4 compares (we're still stuck on 2.4) According to this: http://www.uwsg.iu.edu/hypermail/linux/kernel/0210.1/0011.html 2.6 with swapiness of 0% is same as 2.4.19 - I assume 2.4.19's VM is the same as 2.4.26 (given feature freeze). I have always been completely unimpressed with the 2.4 VM - before and after the big change in ~2.4.10. It has *always* preferred to use cache in preference to a recently used application. So will this still apply to 2.6 with swapiness of 0%? I might try to get my sysadmin to put on 2.6, becuase 2.4 is quite unusable for some of the work I do (if I need mozilla at the same time as my visualisation software, which allocates a good 3/4 of RAM, after reading a file that is about that size, leaving still enough for mozilla and X combined, mozilla and parts of X still get swapped out - and the cahce is wasted, since I only ever read the file once, and it is written on another host) -- TimC -- http://astronomy.swin.edu.au/staff/tconnors/ "32-bit patch for a 16-bit GUI shell running on top of an 8-bit operating system written for a 4-bit processor by a 2-bit company who cannot stand 1 bit of competition." - 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/