Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932756Ab1DZBVB (ORCPT ); Mon, 25 Apr 2011 21:21:01 -0400 Received: from mail-gx0-f174.google.com ([209.85.161.174]:53629 "EHLO mail-gx0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932194Ab1DZBVA convert rfc822-to-8bit (ORCPT ); Mon, 25 Apr 2011 21:21:00 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type:content-transfer-encoding; b=D8tbJYI9BJf+N/Hd0pDwDAjpItqYOFqbqXHl6Vy4opEtw37P4U0MJHgBy74DlLgxjp YWxdy2mmwyWb8w7MaVDc4mayVHmJZnxtcTOfB/jbe1DvbAIFUv1MCYPAeqejka1YFSfZ C/b9gsKkFOH/QTF4jI4jClU09uoD6mqgoqAgk= MIME-Version: 1.0 In-Reply-To: <1303760837.4865.22.camel@laptop> References: <1303728272-11408-1-git-send-email-leemgs1@gmail.com> <1303760837.4865.22.camel@laptop> Date: Tue, 26 Apr 2011 10:20:58 +0900 Message-ID: Subject: Re: [PATCH 0/4] munmap: Flexible mem unmap operation interface for scheduling latency From: Geunsik Lim To: Peter Zijlstra Cc: Ingo Molnar , Andrew Morton , Thomas Gleixner , "H. Peter Anvin" , Hugh Dickins , Steven Rostedt , Darren Hart , linux-kernel , linux-rt-users Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2421 Lines: 60 On Tue, Apr 26, 2011 at 4:47 AM, Peter Zijlstra wrote: > On Mon, 2011-04-25 at 19:44 +0900, Geunsik Lim wrote: >>     Originally, We aim to not hold locks for too long (for scheduling latency reasons). >>     So zap pages in ZAP_BLOCK_SIZE byte counts. >>     This means we need to return the ending mmu_gather to the caller. > > Please have a look at the mmu_gather rewrite that hit -mm last week, > that completely does away with ZAP_BLOCK_SIZE and renders these patches > obsolete. Yes. I also checked the patch that you stated at LKML mailing list previously. In my thinking. I want to keep ZAP_BLOCK_SIZE related contents that adjusted by Ingo, Robert, Andrew, and so on a long time ago because I believe that we can overcome below problems sufficiently in real world. . LKML archive - http://lkml.org/lkml/2002/7/24/273 . LKML archive - http://lkml.org/lkml/2004/9/14/101 In my experience, I did overcome below problems with this patch based on ZAP_BLOCK_SIZE. 1) To solve temporal CPU contention (e.g: case that cpu contention is 93% ~ 96% according to mmap/munmap to access mass files ) 2) To get real-time or real-fast selectively on specified linux system ( demo: http://www.youtube.com/watch?v=PxcgvDTY5F0 ) > > Also, -rt doesn't care since it already has preemptible mmu_gather. > > Furthermore: > >> +L:     linux-rt-users@vger.kernel.org Sorry. I think that I have to add "linux-rt-users@vger.kernel.org" because this patch is related to scheduling latencies although this modification is in ./linux-2.6/mm/ directory. I will remove "+L: linux-rt-users******" if really linux-rt-users mailing list can not care. > > is complete crap, linux-rt-users is _NOT_ a development list. > > -- Regards, Geunsik Lim ( Samsung Electronics ) Blog : http://blog.naver.com/invain/ e-Mail: geunsik.lim@samsung.com            leemgs@gmail.com , leemgs1@gmail.com -- 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/ -- 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/