From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932849AbWF3Rgb (ORCPT ); Fri, 30 Jun 2006 13:36:31 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932854AbWF3Rga (ORCPT ); Fri, 30 Jun 2006 13:36:30 -0400 Received: from gprs189-60.eurotel.cz ([160.218.189.60]:57325 "EHLO amd.ucw.cz") by vger.kernel.org with ESMTP id S932849AbWF3Rg3 (ORCPT ); Fri, 30 Jun 2006 13:36:29 -0400 Date: Fri, 30 Jun 2006 19:36:05 +0200 From: Pavel Machek To: Nigel Cunningham Cc: Greg KH , Jens Axboe , "Rafael J. Wysocki" , linux-kernel@vger.kernel.org Subject: Re: [Suspend2][ 0/9] Extents support. Message-ID: <20060630173605.GA4464@elf.ucw.cz> References: <20060626165404.11065.91833.stgit@nigel.suspend2.net> <200606290825.50674.nigel@suspend2.net> <20060628224428.GC27526@elf.ucw.cz> <200606290914.58784.nigel@suspend2.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <200606290914.58784.nigel@suspend2.net> X-Warning: Reading this can be dangerous to your mental health. User-Agent: Mutt/1.5.11+cvs20060126 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Hi! > > > That's not true. The compression and encryption support add ~1000 lines, > > > as you pointed out the other day. If I moved compression and encryption > > > support to userspace, I'd remove 1000 lines and: > > > > > > - add more code for getting the pages copied to and from userspace > > > > No, if your main loop is already in userspace, you do not need to add > > any more code. And you'd save way more than 1000 lines: > > > > * encryption/compression can be removed > > > > * but that means that writer plugins/filters can be removed > > > > * if you do compress/encrypt in userspace, you can remove that ugly > > netlink thingie, and just display progress in userspace, too > > > > ...and then, image writing can be moved to userspace... > > > > * swapfile support > > > > * partition support > > > > * plus their plugin infrastructure. > > That's going way beyond your inital suggestion. And you haven't responded to > the other points (which have instead been deleted). Well, you were arguing that in uswsusp only "thin layer" is in userspace, and I think I've just shown you it is more thick than you think. Of course I deleted your other points, or did you really want me to argue with "copying from userspace is slow"? Hint: memory is 3GB/sec, while disk is 50MB/sec. Pavel -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html