From mboxrd@z Thu Jan 1 00:00:00 1970 From: Daniel Pittman Subject: Re: Re: [PATCH] Remove process freezer from suspend to RAM pathway Date: Fri, 06 Jul 2007 15:45:17 +1000 Message-ID: <87r6nmozki.fsf@rimspace.net> References: <18059.10554.955290.148535@cargo.ozlabs.ibm.com> <200707051528.34754.oliver@neukum.org> <20070705134632.GA22177@srcf.ucam.org> <200707051609.25887.rjw@sisk.pl> <20070705142318.GA22598@srcf.ucam.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: In-Reply-To: <20070705142318.GA22598@srcf.ucam.org> (Matthew Garrett's message of "Thu, 5 Jul 2007 15:23:18 +0100") List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: linux-pm-bounces@lists.linux-foundation.org Errors-To: linux-pm-bounces@lists.linux-foundation.org To: Matthew Garrett Cc: Miklos Szeredi , linux-kernel@vger.kernel.org, pavel@ucw.cz, johannes@sipsolutions.net, linux-pm@lists.linux-foundation.org List-Id: linux-pm@vger.kernel.org Matthew Garrett writes: > On Thu, Jul 05, 2007 at 04:09:24PM +0200, Rafael J. Wysocki wrote: >> On Thursday, 5 July 2007 15:46, Matthew Garrett wrote: >> > I have a model for STD that avoids the need to freeze the entirity of >> > userspace, but I need to find some more time to flesh it out. >> >> You can just describe it, as far as I'm concerned. :-) > > The basic model is that nobody's really described a use-case where we > actually care about restoring system state. What people want is to be > able to restore application state. So, arguably, what we want isn't to > save the entire kernel state and application state in one go because we > can reconstruct a huge amount of that afterwards. [...] > I've mocked up a basic implementation using cryopid, but it's somewhat > limited by the lack of support for sockets. I'd like to move more of > the smarts into the kernel (Hurray, checkpointing!) and then see how > much hardware support ends up horifically broken. You might want to look at the checkpoint / migration support in the OpenVZ kernel in relation to this. That does work to dump the state of a running "virtual environment" complete with applications to disk, move it to another running kernel and restore the content. That might, perhaps, help with the prototype of this? Regards, Daniel