Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S267212AbUJBCaO (ORCPT ); Fri, 1 Oct 2004 22:30:14 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S267232AbUJBCaO (ORCPT ); Fri, 1 Oct 2004 22:30:14 -0400 Received: from mail-13.iinet.net.au ([203.59.3.45]:14483 "HELO mail.iinet.net.au") by vger.kernel.org with SMTP id S267212AbUJBCaI (ORCPT ); Fri, 1 Oct 2004 22:30:08 -0400 Message-ID: <415E12A9.7000507@cyberone.com.au> Date: Sat, 02 Oct 2004 12:30:01 +1000 From: Nick Piggin User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.7.2) Gecko/20040820 Debian/1.7.2-4 X-Accept-Language: en MIME-Version: 1.0 To: Marcelo Tosatti CC: linux-mm@kvack.org, akpm@osdl.org, arjanv@redhat.com, linux-kernel@vger.kernel.org Subject: Re: [RFC] memory defragmentation to satisfy high order allocations References: <20041001182221.GA3191@logos.cnet> In-Reply-To: <20041001182221.GA3191@logos.cnet> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1050 Lines: 35 Marcelo Tosatti wrote: > >With such a thing in place we can build a mechanism for kswapd >(or a separate kernel thread, if needed) to notice when we are low on >high order pages, and use the coalescing algorithm instead blindly >freeing unique pages from LRU in the hope to build large physically >contiguous memory areas. > >Comments appreciated. > > Hi Marcelo, Seems like a good idea... even with regular dumb kswapd "merging", you may easily get stuck for example on systems without swap... Anyway, I'd like to get those beat kswapd patches in first. Then your mechanism just becomes something like: if order-0 pages are low { try to free memory } else if order-1 or higher pages are low { try to coalesce_memory if that fails, try to free memory } - 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/