From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from smtp1.linuxfoundation.org (smtp1.linux-foundation.org [172.17.192.35]) by mail.linuxfoundation.org (Postfix) with ESMTPS id F0F86411 for ; Mon, 19 Oct 2015 19:32:33 +0000 (UTC) Received: from mail-lf0-f45.google.com (mail-lf0-f45.google.com [209.85.215.45]) by smtp1.linuxfoundation.org (Postfix) with ESMTPS id 50751124 for ; Mon, 19 Oct 2015 19:32:33 +0000 (UTC) Received: by lffy185 with SMTP id y185so120782842lff.2 for ; Mon, 19 Oct 2015 12:32:31 -0700 (PDT) Date: Mon, 19 Oct 2015 15:32:22 -0400 From: Jerome Glisse To: Dan Williams Message-ID: <20151019193221.GA7936@gmail.com> References: <561FD92D.6010309@sr71.net> <20151016210820.GA23471@gmail.com> <20151019182923.GB5907@thunk.org> <20151019185220.GA3068@thunk.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Cc: ksummit-discuss@lists.linuxfoundation.org Subject: Re: [Ksummit-discuss] ZONE_DEVICE and Persistent Memory (was: Re: Draft agenda for the kernel summit) List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Mon, Oct 19, 2015 at 12:23:47PM -0700, Dan Williams wrote: > On Mon, Oct 19, 2015 at 11:52 AM, Theodore Ts'o wrote: > > On Mon, Oct 19, 2015 at 02:29:23PM -0400, Theodore Ts'o wrote: > >> On Fri, Oct 16, 2015 at 05:08:21PM -0400, Jerome Glisse wrote: > >> > On Thu, Oct 15, 2015 at 09:49:49AM -0700, Dave Hansen wrote: > >> > > On 10/14/2015 05:17 PM, Dan Williams wrote: > >> > > > I am wondering if it would be productive / good use of time to do a > >> > > > direction check on the mm changes being done in support of large > >> > > > persistent memory devices. > >> > > > >> > > I think there's probably an even wider discussion that we should have here. > >> > > > >> > > Beyond just ZONE_DEVICE, the sheer number of memory types is increasing > >> > > fast, and our current solutions are, at best, inconsistent. We currently > >> > > handle memory types as new zones, repurposed zones, pageblocks inside > >> > > zones, or faux NUMA nodes. > >> > > > >> > > Are our current solutions too erratic? > >> > > Do we need to solve these problems generally, or are we going to kill > >> > > ourselves trying to make everyone happy? > >> > > What types do we ignore today, but shouldn't? > >> > > What types are coming down the pike? > >> > > >> > I think what i am working on (HMM and how to leverage GPU memory that is > >> > not accessible by the CPU) apply here too. All features i am working on > >> > imply that i have to dig through layers of code seeing if i can abuse an > >> > existing mechanism to achieve something new. > >> > > >> > So i definitly think we should discuss where we are and where we want to > >> > be. > >> > >> Dan, would you be willing to kick off the discussion? > > > > Oops, sorry, it was pointed out to me that Dan isn't going to be at > > the Kernel Summit. Jerome, would you be willing to kick off the > > discussion and report back to Dan? > > Well, you were right the first time ;-), I'm booked and registered. > > Yes, I'd be willing to kick off the discussion. I can help keeping the discussion going on :)