From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760248AbXEMTBK (ORCPT ); Sun, 13 May 2007 15:01:10 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755548AbXEMTA5 (ORCPT ); Sun, 13 May 2007 15:00:57 -0400 Received: from mx1.redhat.com ([66.187.233.31]:39116 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757475AbXEMTA4 (ORCPT ); Sun, 13 May 2007 15:00:56 -0400 Message-ID: <46476049.2090806@redhat.com> Date: Sun, 13 May 2007 15:00:25 -0400 From: Rik van Riel Organization: Red Hat, Inc User-Agent: Thunderbird 1.5.0.7 (X11/20061008) MIME-Version: 1.0 To: Rodrigo Amestica CC: linux-kernel@vger.kernel.org Subject: Re: is linux still a none swappable kernel? References: <464746EC.10608@nrao.edu> In-Reply-To: <464746EC.10608@nrao.edu> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Rodrigo Amestica wrote: > In some older posts I have read that memory allocations via kmalloc > and vmalloc are not swappable, that is, these memory chunks are not > paged out to swap area. Is this still the case with linux kernel 2.6? Yes. Unswappable kernel memory is simpler and faster. Over the last 15 years, the memory requirements of the Linux kernel have grown maybe a factor 10, while the memory of computers has grown by a factor of 1000. The data structures that grow with memory (mostly the mem_map[] array of page structs) has actually gotten smaller since the 2.4 kernel and now takes under 1% of memory even on x86-64. There really is no good reason for swapping kernel memory nowadays. -- Politics is the struggle between those who want to make their country the best in the world, and those who believe it already is. Each group calls the other unpatriotic.