From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S266304AbUHDQtZ (ORCPT ); Wed, 4 Aug 2004 12:49:25 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S267350AbUHDQtZ (ORCPT ); Wed, 4 Aug 2004 12:49:25 -0400 Received: from imladris.demon.co.uk ([193.237.130.41]:17931 "EHLO phoenix.infradead.org") by vger.kernel.org with ESMTP id S266304AbUHDQtY (ORCPT ); Wed, 4 Aug 2004 12:49:24 -0400 Date: Wed, 4 Aug 2004 17:48:56 +0100 From: Christoph Hellwig To: Herbert Xu Cc: Christoph Hellwig , ganesh.venkatesan@intel.com, jgarzik@pobox.com, netdev@oss.sgi.com, linux-kernel@vger.kernel.org Subject: Re: [PATCH 3/12 2.4] e1000 - use vmalloc for data structures not shared with h/w Message-ID: <20040804174856.B24545@infradead.org> Mail-Followup-To: Christoph Hellwig , Herbert Xu , ganesh.venkatesan@intel.com, jgarzik@pobox.com, netdev@oss.sgi.com, linux-kernel@vger.kernel.org References: <20040729192519.A6235@infradead.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.2.5.1i In-Reply-To: ; from herbert@gondor.apana.org.au on Sat, Jul 31, 2004 at 05:38:11PM +1000 X-SRS-Rewrite: SMTP reverse-path rewritten from by phoenix.infradead.org See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Sat, Jul 31, 2004 at 05:38:11PM +1000, Herbert Xu wrote: > > No, it's not. vmalloc needs virtual space that's rather limited (e.g. 64MB > > on PAE x86) in addition to physical memory. Unless you do really big > > allocations stay away from vmalloc. > > How big is really big? 64K? 256K? 1M? Well, the VM deals with big-order (aka bigger than page size) allocations rather bad, so for allocation during any I/O I'd stick to allocation smaller than that (and certainly no vmalloc!), for init-time allocations order 1 is fine, maybe even order 2 or three.