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, 26 Mar 2001 10:44:52 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Mon, 26 Mar 2001 10:44:43 -0500 Received: from penguin.roanoke.edu ([199.111.154.8]:12818 "EHLO penguin.roanoke.edu") by vger.kernel.org with ESMTP id ; Mon, 26 Mar 2001 10:44:33 -0500 Message-ID: <3ABF63D3.D0C8558@linuxjedi.org> Date: Mon, 26 Mar 2001 10:44:19 -0500 From: "David L. Parsley" X-Mailer: Mozilla 4.76 [en] (X11; U; Linux 2.4.1-pre7 i686) X-Accept-Language: en MIME-Version: 1.0 To: linux-kernel@vger.kernel.org Subject: /proc/sys/vm/freepages read-only?!? 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 Hi, I'm trying to do some vm tuning for diskless (and therefore swapless) devices. (I'm working on a distro that tftp's packages and runs entirely in RAM) Even on an X terminal with 64MB RAM, badly behaved apps can use lots of ram in the Xserver, and what I'm seeing is a hang. The box is usually still pingable, just unresponsive. I'm using cramfs pretty heavily, and I think what's occuring is that the terminal gets too low on freepages, and since pages used by X can't be swapped out, the box starts thrashing the vm and is unable to get pages to uncompress into. My first thought was echo (bigger numbers) > /proc/sys/vm/freepages - but lo! - it's not writable anymore. I found comments in page_alloc.c indicating it had to be read-only, but it seems it's only a safety precaution. Something along the lines of values too small being 'bad bad'. help? David -- David L. Parsley Network Administrator Roanoke College