From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756113AbXGJMiU (ORCPT ); Tue, 10 Jul 2007 08:38:20 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752607AbXGJMiE (ORCPT ); Tue, 10 Jul 2007 08:38:04 -0400 Received: from hellhawk.shadowen.org ([80.68.90.175]:1034 "EHLO hellhawk.shadowen.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755262AbXGJMiB (ORCPT ); Tue, 10 Jul 2007 08:38:01 -0400 Message-ID: <46937DA2.4040302@shadowen.org> Date: Tue, 10 Jul 2007 13:37:54 +0100 From: Andy Whitcroft User-Agent: Icedove 1.5.0.9 (X11/20061220) MIME-Version: 1.0 To: Andrew Morton CC: linux-kernel@vger.kernel.org, Mel Gorman , Christoph Lameter Subject: clam References: <20070710013152.ef2cd200.akpm@linux-foundation.org> In-Reply-To: <20070710013152.ef2cd200.akpm@linux-foundation.org> Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Andrew Morton wrote: [...] > lumpy-reclaim-v4.patch > have-kswapd-keep-a-minimum-order-free-other-than-order-0.patch > only-check-absolute-watermarks-for-alloc_high-and-alloc_harder-allocations.patch > > Lumpy reclaim. In a similar situation to Mel's patches. Stuck due to > general lack or interest and effort. The lumpy reclaim patches originally came out of work to support Mel's anti-fragmentation work. As such I think they have become somewhat attached to those patches. Whilst lumpy is most effective where placement controls are in place as offered by Mel's work, we see benefit from reduction in the "blunderbuss" effect when we reclaim at higher orders. While placement control is pretty much required for the very highest orders such as huge page size, lower order allocations are benefited in terms of lower collateral damage. There are now a few areas other than huge page allocations which can benefit. Stacks are still order 1. Jumbo frames want higher order contiguous pages for there incoming hardware buffers. SLUB is showing performance benefits from moving to a higher allocation order. All of these should benefit from more aggressive targeted reclaim, indeed I have been surprised just how often my test workloads trigger lumpy at order 1 to get new stacks. Truly representative work loads are hard to generate for some of these. Though we have heard some encouraging noises from those who can reproduce these problems. [...] -apw