From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail6.bemta7.messagelabs.com (mail6.bemta7.messagelabs.com [216.82.255.55]) by kanga.kvack.org (Postfix) with ESMTP id B5D8D9000BD for ; Thu, 29 Sep 2011 00:49:16 -0400 (EDT) Received: from m2.gw.fujitsu.co.jp (unknown [10.0.50.72]) by fgwmail5.fujitsu.co.jp (Postfix) with ESMTP id EA5103EE081 for ; Thu, 29 Sep 2011 13:49:10 +0900 (JST) Received: from smail (m2 [127.0.0.1]) by outgoing.m2.gw.fujitsu.co.jp (Postfix) with ESMTP id D32B745DE7A for ; Thu, 29 Sep 2011 13:49:10 +0900 (JST) Received: from s2.gw.fujitsu.co.jp (s2.gw.fujitsu.co.jp [10.0.50.92]) by m2.gw.fujitsu.co.jp (Postfix) with ESMTP id B29FF45DE61 for ; Thu, 29 Sep 2011 13:49:10 +0900 (JST) Received: from s2.gw.fujitsu.co.jp (localhost.localdomain [127.0.0.1]) by s2.gw.fujitsu.co.jp (Postfix) with ESMTP id A5A5C1DB803C for ; Thu, 29 Sep 2011 13:49:10 +0900 (JST) Received: from m107.s.css.fujitsu.com (m107.s.css.fujitsu.com [10.240.81.147]) by s2.gw.fujitsu.co.jp (Postfix) with ESMTP id 6384D1DB802C for ; Thu, 29 Sep 2011 13:49:10 +0900 (JST) Date: Thu, 29 Sep 2011 13:48:16 +0900 From: KAMEZAWA Hiroyuki Subject: Re: [PATCH V10 0/6] mm: frontswap: overview (and proposal to merge at next window) Message-Id: <20110929134816.7f29bf46.kamezawa.hiroyu@jp.fujitsu.com> In-Reply-To: <22173398-de03-43ef-abe4-a3f3231dd2e9@default> References: <20110915213305.GA26317@ca-server1.us.oracle.com 20110928151558.dca1da5e.kamezawa.hiroyu@jp.fujitsu.com> <22173398-de03-43ef-abe4-a3f3231dd2e9@default> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: 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 On Wed, 28 Sep 2011 07:09:18 -0700 (PDT) Dan Magenheimer wrote: > > 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. > I'm afraid that users will lose data on memory of frontswap/zcache/tmem by power-off, hibernation. How about adding internal hooks to disable/sync frontswap itself before hibernation ? difficult ? Thanks, -Kame -- 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/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org