Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261436AbUJ0BJu (ORCPT ); Tue, 26 Oct 2004 21:09:50 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261520AbUJ0BJu (ORCPT ); Tue, 26 Oct 2004 21:09:50 -0400 Received: from mail-relay-4.tiscali.it ([213.205.33.44]:63375 "EHLO mail-relay-4.tiscali.it") by vger.kernel.org with ESMTP id S261436AbUJ0BJs (ORCPT ); Tue, 26 Oct 2004 21:09:48 -0400 Date: Wed, 27 Oct 2004 03:10:43 +0200 From: Andrea Arcangeli To: Rik van Riel Cc: Nick Piggin , Andrew Morton , linux-kernel@vger.kernel.org Subject: Re: lowmem_reserve (replaces protection) Message-ID: <20041027011043.GQ14325@dualathlon.random> References: <20041027005425.GO14325@dualathlon.random> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-GPG-Key: 1024D/68B9CB43 13D9 8355 295F 4823 7C49 C012 DFA1 686E 68B9 CB43 X-PGP-Key: 1024R/CB4660B9 CC A0 71 81 F4 A0 63 AC C0 4B 81 1D 8C 15 C8 E5 User-Agent: Mutt/1.5.6i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1232 Lines: 25 On Tue, Oct 26, 2004 at 09:00:11PM -0400, Rik van Riel wrote: > However, doesn't the protection also serve a purpose for > NUMA fallback ? How is that handled by your code ? It doesn't. The only reason any NUMA folk were interested in this stuff was to nuke the incremental min weak band-aid that Linus introduced in 2.4 while rejecting my real lowmem_reserve algorithm (that has been reinvented in 2.6.5 first and against 2.6.7 with the name of protection but still buggy and disabled by default, so not very useful.., especially after even the incremental-min was gone from 2.6.8+). NUMA folks only want to nuke the incremental-min hack since that escalated to huge waste of ram on the hundred nodes. the major point of the rework in the protection algorithm happened between 2.6.5 and 2.6.8 was to drop any NUMA effect from the algorithm that guarantees DMA allocations on x86-64 and NORMAL allocations on x86 PAE. So being it unrelated to NUMA is a feature as far as I can tell. - 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/