From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Wed, 7 Jun 2000 22:24:21 +0100 From: "Stephen C. Tweedie" Subject: Re: journaling & VM (was: Re: reiserfs being part of the kernel: it'snot just the code) Message-ID: <20000607222421.H30951@redhat.com> References: <393E8AEF.7A782FE4@reiser.to> <20000607205819.E30951@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: ; from quintela@fi.udc.es on Wed, Jun 07, 2000 at 10:56:17PM +0200 Sender: owner-linux-mm@kvack.org Return-Path: To: "Juan J. Quintela" Cc: "Stephen C. Tweedie" , Rik van Riel , Hans Reiser , bert hubert , linux-kernel@vger.rutgers.edu, Chris Mason , linux-mm@kvack.org, Alexander Zarochentcev List-ID: Hi, On Wed, Jun 07, 2000 at 10:56:17PM +0200, Juan J. Quintela wrote: > > >> I'd like to be able to keep stuff simple in the shrink_mmap > >> "equivalent" I'm working on. Something like: > >> > >> if (PageDirty(page) && page->mapping && page->mapping->flush) > >> maxlaunder -= page->mapping->flush(); > > sct> That looks ideal. > > But this is supposed to flush that _page_, at least in the normal > case. All transactional filesystems will have ordering constraints which the core VM cannot know about. In that case, the filesystem may simply have no choice about cleaning and unpinning pages in a given order. For actually removing a page from memory, evicting precisely the right page is far more important, but for writeback, it's controlling the amount of dirty/pinned data from the various different sources which counts. Cheers, Stephen -- 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.eu.org/Linux-MM/