Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1765260AbXINCib (ORCPT ); Thu, 13 Sep 2007 22:38:31 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1757336AbXINCiV (ORCPT ); Thu, 13 Sep 2007 22:38:21 -0400 Received: from netops-testserver-3-out.sgi.com ([192.48.171.28]:38983 "EHLO relay.sgi.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751174AbXINCiU (ORCPT ); Thu, 13 Sep 2007 22:38:20 -0400 Date: Thu, 13 Sep 2007 19:38:16 -0700 (PDT) From: Christoph Lameter X-X-Sender: clameter@schroedinger.engr.sgi.com To: Mel Gorman cc: Nick Piggin , andrea@suse.de, torvalds@linux-foundation.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, Christoph Hellwig , William Lee Irwin III , David Chinner , Jens Axboe , Badari Pulavarty , Maxim Levitsky , Fengguang Wu , swin wang , totty.lu@gmail.com, hugh@veritas.com, joern@lazybastard.org Subject: Re: [00/41] Large Blocksize Support V7 (adds memmap support) In-Reply-To: <20070913094030.GA22778@skynet.ie> Message-ID: References: <20070911060349.993975297@sgi.com> <200709111617.03586.nickpiggin@yahoo.com.au> <200709121246.08833.nickpiggin@yahoo.com.au> <20070913094030.GA22778@skynet.ie> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1573 Lines: 35 On Thu, 13 Sep 2007, Mel Gorman wrote: > Surely, we'll be able to detect the situation where the memory is really > contiguous as a fast path and have a slower path where fragmentation was > a problem. Yes I have a draft here now of a virtual compound page solution that I am testing with SLUB. Page allocator first tries to allocate a contiguous page. If that is not possible then we string together a contiguous page through order 0 allocs and vmalloc. > The only implementation question about these patches that hasn't been addressed > is the mmap() support. What's wrong with it in it's current form. Can it be > fixed or if it's fundamentally screwed etc. That has fallen by the > wayside. Yes I have not heard about those. Got some more ideas how to clean it up even more in the meantime. No feedback usually means no objections..... > I am *very* wary of using reserve pools for anything other than > emergency situations. If nothing else pools == wasted memory + a sizing > problem. But hey, it is one option. Well we need the page pools anyways for large page sizes > MAX_ORDER. But > Are we going to agree on some sort of plan or are we just going to > handwave ourselves to death? Ill try to do the virtual mapped compound pages. Hopefully that will allow fallback for compound pages in a generic way. - 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/