From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755989AbXFOPGV (ORCPT ); Fri, 15 Jun 2007 11:06:21 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754179AbXFOPGI (ORCPT ); Fri, 15 Jun 2007 11:06:08 -0400 Received: from e4.ny.us.ibm.com ([32.97.182.144]:40497 "EHLO e4.ny.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755683AbXFOPGG (ORCPT ); Fri, 15 Jun 2007 11:06:06 -0400 Subject: Re: [patch 00/14] Page cache cleanup in anticipation of Large Blocksize support From: Dave Kleikamp To: Andrew Morton Cc: Christoph Lameter , linux-kernel@vger.kernel.org, hch@infradead.org In-Reply-To: <20070614150417.c73fb6b9.akpm@linux-foundation.org> References: <20070614193839.878721298@sgi.com> <20070614130645.cabdff1b.akpm@linux-foundation.org> <20070614143248.736312f8.akpm@linux-foundation.org> <20070614150417.c73fb6b9.akpm@linux-foundation.org> Content-Type: text/plain Date: Fri, 15 Jun 2007 10:05:59 -0500 Message-Id: <1181919959.10658.9.camel@kleikamp.austin.ibm.com> Mime-Version: 1.0 X-Mailer: Evolution 2.8.3 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 2007-06-14 at 15:04 -0700, Andrew Morton wrote: > > On Thu, 14 Jun 2007 14:37:33 -0700 (PDT) Christoph Lameter wrote: > > On Thu, 14 Jun 2007, Andrew Morton wrote: > > > > > We want the 100% case. > > > > Yes that is what we intend to do. Universal support for larger blocksize. > > I.e. your desktop filesystem will use 64k page size and server platforms > > likely much larger. > > With 64k pagesize the amount of memory required to hold a kernel tree (say) > will go from 270MB to 1400MB. This is not an optimisation. > > Several 64k pagesize people have already spent time looking at various > tail-packing schemes to get around this serious problem. And that's on > _server_ class machines. Large ones. I don't think > laptop/desktop/samll-server machines would want to go anywhere near this. I'm one of the ones investigating 64 KB pagesize tail-packing schemes, and I believe Christoph's cleanups will reduce the intrusiveness and improve the readability of a tail-packing solution. I'll add my vote in support of these patches. Thanks, Shaggy -- David Kleikamp IBM Linux Technology Center