From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail138.messagelabs.com (mail138.messagelabs.com [216.82.249.35]) by kanga.kvack.org (Postfix) with ESMTP id 14A316B0047 for ; Fri, 27 Feb 2009 06:33:39 -0500 (EST) Date: Fri, 27 Feb 2009 12:33:33 +0100 From: Nick Piggin Subject: Re: [PATCH 20/20] Get rid of the concept of hot/cold page freeing Message-ID: <20090227113333.GA21296@wotan.suse.de> References: <20090223233030.GA26562@csn.ul.ie> <20090223155313.abd41881.akpm@linux-foundation.org> <20090224115126.GB25151@csn.ul.ie> <20090224160103.df238662.akpm@linux-foundation.org> <20090225160124.GA31915@csn.ul.ie> <20090225081954.8776ba9b.akpm@linux-foundation.org> <20090226163751.GG32756@csn.ul.ie> <20090226171549.GH32756@csn.ul.ie> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: owner-linux-mm@kvack.org To: Christoph Lameter Cc: Mel Gorman , Andrew Morton , linux-mm@kvack.org, penberg@cs.helsinki.fi, riel@redhat.com, kosaki.motohiro@jp.fujitsu.com, hannes@cmpxchg.org, linux-kernel@vger.kernel.org, ming.m.lin@intel.com, yanmin_zhang@linux.intel.com List-ID: On Thu, Feb 26, 2009 at 12:30:45PM -0500, Christoph Lameter wrote: > On Thu, 26 Feb 2009, Mel Gorman wrote: > > > > I tried the general use of a pool of zeroed pages back in 2005. Zeroing > > > made sense only if the code allocating the page did not immediately touch > > > the cachelines of the page. > > > > Any feeling as to how often this was the case? > > Not often enough to justify the merging of my patches at the time. This > was publicly discussed on lkml: > > http://lkml.indiana.edu/hypermail/linux/kernel/0503.2/0482.html > > > Indeed, any gain if it existed would be avoiding zeroing the pages used > > by userspace. The cleanup would be reducing the amount of > > architecture-specific code. > > > > I reckon it's worth an investigate but there is still other lower-lying > > fruit. > > I hope we can get rid of various ugly elements of the quicklists if the > page allocator would offer some sort of support. I would think that the Only if it provides significant advantages over existing quicklists or adds *no* extra overhead to the page allocator common cases. :) -- 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