From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Mon, 25 Jun 2001 05:24:31 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Mon, 25 Jun 2001 05:24:12 -0400 Received: from hermine.idb.hist.no ([158.38.50.15]:7186 "HELO hermine.idb.hist.no") by vger.kernel.org with SMTP id ; Mon, 25 Jun 2001 05:24:04 -0400 Message-ID: <3B3702B5.13554207@idb.hist.no> Date: Mon, 25 Jun 2001 11:21:57 +0200 From: Helge Hafting X-Mailer: Mozilla 4.76 [en] (X11; U; Linux 2.4.6-pre5 i686) X-Accept-Language: no, en MIME-Version: 1.0 To: Maciej Zenczykowski , linux-kernel@vger.kernel.org Subject: Re: Thrashing WITHOUT swap. In-Reply-To: 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 Maciej Zenczykowski wrote: > Now my question is how can it be > thrashing with swap explicitly turned off? Easy. Linux throws executables out from memory because they _can_ be fetched again from disk. Yes - this definitely gives trashing if you loose almost all your executables this way. > [oh just to make stuff even > funnier netscape is at nice -19 (i.e. lower priority)] That makes no difference. nice'ing netscape means it use less _cpu when other things want cpu_, it can still over-spend memory! > top gives me: > mem: 62144k av, 61180k used, 956k free, 0k shrd, 76 buff, 2636 cached > swap: 0k av, 0k used, 0k free [as expected] File i/o becomes a pain with so few buffers and cache pages left, and then your file i/o and the executable fetching competes for the disk. No wonder it got slow, and laptop disks aren't usually that fast either... > So my basic question is what can I do to fix this? Looks like you were 3M away from running completely out of memory. Turn on that swap partition you mentioned, your machine will degrade much more gracefully. It'll keep more cache around and be able to get rid of unused data instead of just dropping executables. Some of the code is used a lot after all. If it still is too slow - add RAM or run fewer/smaller apps. Opera is a low-memory alternative to netscape. Avoiding gnome/kde apps when plain X apps are available is also a good idea when you're short on memory. Using low resolution and low-color modes might help a little if you do lot of graphics. But then you might not want that. Helge Hafting