From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <418DADDC.1030601@sgi.com> Date: Sat, 06 Nov 2004 23:08:44 -0600 From: Ray Bryant MIME-Version: 1.0 Subject: Re: manual page migration, revisited... References: <418C03CD.2080501@sgi.com> <1099695742.4507.114.camel@desktop.cunninghams> <20041106174857.GA23420@logos.cnet> In-Reply-To: <20041106174857.GA23420@logos.cnet> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: Marcelo Tosatti Cc: Nigel Cunningham , Hirokazu Takahashi , Linux Memory Management List-ID: Marcelo Tosatti wrote: >>You may not even need any kernel patches to accomplish this. Bernard >>Blackham wrote some code called cryopid: http://cryopid.berlios.de/. I >>haven't tried it myself, but it sounds like it might be at least part of >>what you're after. > > > Hi Ray, Nigel, > > And the swsusp code itself, isnt it what its doing? Stopping all processes, > saving their memory to disk, and resuming later on. > > You should just need an API to stop a specific process? > I think that sending the process a SIGSTOP is probably good enough to stop it for our purposes. But in addition to that, the reason we stopped the process is so we can start up another process on that node. Now, we can wait for memory pressure to grow to the point that kswap will force out the stopped processes's pages, but, why should the VM have to go to the effort to figure that out? Why not tell them VM somehow, that we don't want these pages in memory, and to please swap them out to make space for the new program that is running? Of course, one can argue that we don't know for sure that the new program will use enough space to force the other process out, but we worry that in that case, the new program could still end up with non-local memory allocation and that is an anathema to the HPC world where we require the good performance that local storage allocation provides. We want the new process that is run on the node to get as good performance as it would have gotten if it had started on an idle node. -- Best Regards, Ray ----------------------------------------------- Ray Bryant 512-453-9679 (work) 512-507-7807 (cell) raybry@sgi.com raybry@austin.rr.com The box said: "Requires Windows 98 or better", so I installed Linux. ----------------------------------------------- -- 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