From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Tue, 12 Oct 2004 09:17:49 -0300 From: Marcelo Tosatti Subject: Re: [RFC] memory defragmentation to satisfy high order allocations Message-ID: <20041012121749.GA10428@logos.cnet> References: <20041012105657.D1D0670463@sv1.valinux.co.jp> <1509480000.1097591191@[10.10.2.4]> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1509480000.1097591191@[10.10.2.4]> Sender: owner-linux-mm@kvack.org Return-Path: To: "Martin J. Bligh" Cc: IWAMOTO Toshihiro , Hirokazu Takahashi , haveblue@us.ibm.com, linux-mm@kvack.org List-ID: On Tue, Oct 12, 2004 at 07:26:32AM -0700, Martin J. Bligh wrote: > >> > iwamoto> I don't think requiring swap is a big deal. If you don't have a > >> > iwamoto> dedicated swap device, which case I think unusual, you can swapon a > >> > iwamoto> regular file. > >> > >> Sure its not a big deal, but nicer if it doesnt require swap. > > > >> For memory defragmentation it is a big deal. > > > > Why? IMO, it isn't very rewarding to tune memory > > migration/defragmentation performance as they involve memory copy > > anyway. > > > > Or, do you want memory defragmentation everywhere, including embedded > > systems? > > Lots of systems nowadays don't have swap configured, not just embedded. > What do we gain from making defrag slower and harder to use, by forcing > it to use swap? Isn't pushing it into the swapcache sufficient? Hi Martin, Yes pushing it to swapcache is sufficient - but doing so requires swap map space (the "index" for swapcache pages is retrieved from swap map space position). As I posted in the other message I'm working on a idr-based cache (migration cache) which should solve things. -- 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: aart@kvack.org