From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754520AbcFPM1r (ORCPT ); Thu, 16 Jun 2016 08:27:47 -0400 Received: from mga02.intel.com ([134.134.136.20]:32892 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754372AbcFPM1n (ORCPT ); Thu, 16 Jun 2016 08:27:43 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.26,480,1459839600"; d="scan'208";a="998902408" Date: Thu, 16 Jun 2016 15:27:35 +0300 From: "Kirill A. Shutemov" To: Michal Hocko Cc: Linus Torvalds , Andrew Morton , Rik van Riel , Mel Gorman , "Huang, Ying" , Minchan Kim , Vinayak Menon , Dave Hansen , linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: Re: [PATCH 1/2] Revert "mm: make faultaround produce old ptes" Message-ID: <20160616122735.GB108167@black.fi.intel.com> References: <1465893750-44080-1-git-send-email-kirill.shutemov@linux.intel.com> <1465893750-44080-2-git-send-email-kirill.shutemov@linux.intel.com> <20160616122001.GJ6836@dhcp22.suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20160616122001.GJ6836@dhcp22.suse.cz> User-Agent: Mutt/1.5.23.1 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Jun 16, 2016 at 02:20:02PM +0200, Michal Hocko wrote: > On Tue 14-06-16 11:42:29, Kirill A. Shutemov wrote: > > This reverts commit 5c0a85fad949212b3e059692deecdeed74ae7ec7. > > > > The commit causes ~6% regression in unixbench. > > Is the regression fully explained? My understanding from the email > thread is that this is suspiciously too high. It is not like I would > be against the revert but having an explanation would be really > appreciated. My understanding is that it's overhead on setting accessed bit: http://lkml.kernel.org/r/20160613125248.GA30109@black.fi.intel.com -- Kirill A. Shutemov