From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Fri, 27 Jul 2007 07:54:07 +0200 From: Nick Piggin Subject: Re: [patch][rfc] remove ZERO_PAGE? Message-ID: <20070727055406.GA22581@wotan.suse.de> References: <20070727021943.GD13939@wotan.suse.de> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: owner-linux-mm@kvack.org Return-Path: To: Linus Torvalds Cc: Andrew Morton , Hugh Dickins , Andrea Arcangeli , Linux Memory Management List List-ID: On Thu, Jul 26, 2007 at 10:29:01PM -0700, Linus Torvalds wrote: > > > On Fri, 27 Jul 2007, Nick Piggin wrote: > > > > I'd like to see if we can get the ball rolling on this again, and try to > > get it in 2.6.24 maybe. Any comments? > > I'd really want real performance numbers. I don't like the "remove it > because I don't like it". I want real numbers for real loads before I'm > really interested. What numbers, though? I can make up benchmarks to show that ZERO_PAGE sucks just as much. The problem I don't think is finding a situatoin that improves without it (we have an extreme case where the Altix livelocked) but to get confidence that nothing is going to blow up. > Last time this came up, the logic behind wanting to remove the zero page > was all screwed up, and it was all based on totally broken premises. So I > really want somethign else than just "I don't like it". I thought that last time this came up you thought it might be good to try out in -mm initially. > Sorry. In the absense of numbers (and not just some made-up branchmark: > something real - I can _easily_ make benchmarks that show that ZERO_PAGE > is wonderful), I'm not at all interested. OK, well what numbers would you like to see? I can always try a few things. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org