From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754646Ab1I1OKM (ORCPT ); Wed, 28 Sep 2011 10:10:12 -0400 Received: from rcsinet15.oracle.com ([148.87.113.117]:43919 "EHLO rcsinet15.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754568Ab1I1OKK convert rfc822-to-8bit (ORCPT ); Wed, 28 Sep 2011 10:10:10 -0400 MIME-Version: 1.0 Message-ID: <22173398-de03-43ef-abe4-a3f3231dd2e9@default> Date: Wed, 28 Sep 2011 07:09:18 -0700 (PDT) From: Dan Magenheimer To: KAMEZAWA Hiroyuki Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, jeremy@goop.org, hughd@google.com, ngupta@vflare.org, Konrad Wilk , JBeulich@novell.com, Kurt Hackel , npiggin@kernel.dk, akpm@linux-foundation.org, riel@redhat.com, hannes@cmpxchg.org, matthew@wil.cx, Chris Mason , sjenning@linux.vnet.ibm.com, jackdachef@gmail.com, cyclonusj@gmail.com, levinsasha928@gmail.com Subject: RE: [PATCH V10 0/6] mm: frontswap: overview (and proposal to merge at next window) References: <20110915213305.GA26317@ca-server1.us.oracle.com 20110928151558.dca1da5e.kamezawa.hiroyu@jp.fujitsu.com> In-Reply-To: <20110928151558.dca1da5e.kamezawa.hiroyu@jp.fujitsu.com> X-Priority: 3 X-Mailer: Oracle Beehive Extensions for Outlook 2.0.1.4.1.0 (410211) [OL 12.0.6557.5001] Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 8BIT X-Source-IP: ucsinet24.oracle.com [156.151.31.67] X-CT-RefId: str=0001.0A090203.4E832AAF.00DD,ss=1,re=0.000,fgs=0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > From: KAMEZAWA Hiroyuki [mailto:kamezawa.hiroyu@jp.fujitsu.com] > Sent: Wednesday, September 28, 2011 12:16 AM > To: Dan Magenheimer > Cc: linux-kernel@vger.kernel.org; linux-mm@kvack.org; jeremy@goop.org; hughd@google.com; > ngupta@vflare.org; Konrad Wilk; JBeulich@novell.com; Kurt Hackel; npiggin@kernel.dk; akpm@linux- > foundation.org; riel@redhat.com; hannes@cmpxchg.org; matthew@wil.cx; Chris Mason; > sjenning@linux.vnet.ibm.com; jackdachef@gmail.com; cyclonusj@gmail.com; levinsasha928@gmail.com > Subject: Re: [PATCH V10 0/6] mm: frontswap: overview (and proposal to merge at next window) > > On Thu, 15 Sep 2011 14:33:05 -0700 > Dan Magenheimer wrote: > > > [PATCH V10 0/6] mm: frontswap: overview (and proposal to merge at next window) > > > > (Note: V9->V10 only change is corrections in debugfs-related code/counters) > > > > (Note to earlier reviewers: This patchset was reorganized at V9 due > > to feedback from Kame Hiroyuki and Andrew Morton. Additionally, feedback > > on frontswap v8 from Andrew Morton also applies to cleancache, to wit: > > (1) change usage of sysfs to debugfs to avoid unnecessary kernel ABIs > > (2) rename all uses of "flush" to "invalidate" > > As a result, additional patches (5of6 and 6of6) were added to this > > series at V9 to patch cleancache core code and cleancache hooks in the mm > > and fs subsystems and update cleancache documentation accordingly.) > > I'm sorry I couldn't catch following... what happens at hibernation ? > frontswap is effectively stopped/skipped automatically ? or contents of > TMEM can be kept after power off and it can be read correctly when > resume thread reads swap ? > > In short: no influence to hibernation ? > I'm sorry if I misunderstand some. Hi Kame -- Hibernation would need to be handled by the tmem backend (e.g. zcache, Xen tmem). In the case of Xen tmem, both save/restore and live migration are fully supported. I'm not sure if zcache works across hibernation; since all memory is kmalloc'ed, I think it should work fine, but it would be an interesting experiment. Thanks, Dan