From: Ankita Garg <ankita@in.ibm.com>
To: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: linux-arm-kernel@lists.infradead.org, linux-mm@kvack.org,
linux-kernel@vger.kernel.org,
linux-pm@lists.linux-foundation.org, svaidy@linux.vnet.ibm.com,
thomas.abraham@linaro.org
Subject: Re: [PATCH 00/10] mm: Linux VM Infrastructure to support Memory Power Management
Date: Fri, 17 Jun 2011 20:58:45 +0530 [thread overview]
Message-ID: <20110617152845.GA13574@in.ibm.com> (raw)
In-Reply-To: <20110616181251.caf484b6.kamezawa.hiroyu@jp.fujitsu.com>
Hi,
On Thu, Jun 16, 2011 at 06:12:51PM +0900, KAMEZAWA Hiroyuki wrote:
> On Thu, 16 Jun 2011 09:50:44 +0530
> Ankita Garg <ankita@in.ibm.com> wrote:
>
> > Hi,
> >
> > On Mon, Jun 13, 2011 at 01:47:01PM +0900, KAMEZAWA Hiroyuki wrote:
> > > On Fri, 27 May 2011 18:01:28 +0530
> > > Ankita Garg <ankita@in.ibm.com> wrote:
> > >
> > > > Hi,
> > > >
> > >
> > > I'm sorry if you've answered already.
> > >
> > > Is memory hotplug is too bad and cannot be enhanced for this purpose ?
> > >
> > > I wonder
> > > - make section-size smaller (IIUC, IBM's system has 16MB section size)
> > >
> > > - add per section statistics
> > >
> > > - add a kind of balloon driver which does software memory offline
> > > (which means making a contiguous chunk of free pages of section_size
> > > by page migration) in background with regard to memory usage statistics.
> > > If system says "need more memory!", balloon driver can online pages.
> > >
> > > can work for your purpose. It can allow you page isolatation and
> > > controls in 16MB unit. If you need whole rework of memory hotplug, I think
> > > it's better to rewrite memory hotplug, too.
> > >
> >
> > Interesting idea, but a few issues -
> >
> > - Correctly predicting memory pressure is difficult and thereby being
> > able to online the required pages at the right time could be a
> > challenge
>
> But it will be required for your purpose, anyway. Isn't it ?
>
> > - Memory hotplug is a heavy operation, so the overhead involved may be
> > high
>
> soft-offline of small amount of pages will not very heavy.
> compaction and cma patches use the same kind of logic.
>
>
> > - Powering off memory is just one of the ways in which memory power could
> > be saved. The platform can also dynamically transition areas of memory
> > into a content-preserving lower power state if it is not referenced
> > for a pre-defined threshold of time. In such a case, we would need a
> > mechanism to soft offline the pages - i.e, no new allocations to be
> > directed to that memory
> >
>
> Hmm, sounds like a similar idea of CleanCache ?
>
> Reusing section is much easier than adding new one.., I think.
>
But sections do not define the granualarity at which memory operations
are done right ? i.e, allocations/deallocations or reclaim cannot be
directed to a section or a group of sections ?
--
Regards,
Ankita Garg (ankita@in.ibm.com)
Linux Technology Center
IBM India Systems & Technology Labs,
Bangalore, India
next prev parent reply other threads:[~2011-06-17 15:29 UTC|newest]
Thread overview: 70+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-05-27 12:31 [PATCH 00/10] mm: Linux VM Infrastructure to support Memory Power Management Ankita Garg
2011-05-27 12:31 ` [PATCH 01/10] mm: Introduce the memory regions data structure Ankita Garg
2011-05-27 15:30 ` Dave Hansen
2011-05-27 18:20 ` Vaidyanathan Srinivasan
2011-05-27 21:31 ` Dave Hansen
2011-05-29 8:16 ` Ankita Garg
2011-05-31 17:34 ` Dave Hansen
2011-06-02 8:54 ` Ankita Garg
2011-05-27 12:31 ` [PATCH 02/10] mm: Helper routines Ankita Garg
2011-05-27 12:31 ` [PATCH 03/10] mm: Init zones inside memory regions Ankita Garg
2011-05-27 12:31 ` [PATCH 04/10] mm: Refer to zones from " Ankita Garg
2011-05-27 12:31 ` [PATCH 05/10] mm: Create zonelists Ankita Garg
2011-05-27 12:31 ` [PATCH 06/10] mm: Verify zonelists Ankita Garg
2011-05-27 12:31 ` [PATCH 07/10] mm: Modify vmstat Ankita Garg
2011-05-27 12:31 ` [PATCH 08/10] mm: Modify vmscan Ankita Garg
2011-05-27 12:31 ` [PATCH 09/10] mm: Reflect memory region changes in zoneinfo Ankita Garg
2011-05-27 12:31 ` [PATCH 10/10] mm: Create memory regions at boot-up Ankita Garg
2011-05-28 14:39 ` Jean-Christophe PLAGNIOL-VILLARD
2011-05-28 7:56 ` [PATCH 00/10] mm: Linux VM Infrastructure to support Memory Power Management Andrew Morton
2011-05-28 13:16 ` Ankita Garg
2011-06-09 18:52 ` Paul E. McKenney
2011-06-10 0:51 ` Kyungmin Park
2011-06-10 15:11 ` Paul E. McKenney
2011-06-10 15:59 ` Matthew Garrett
2011-06-10 16:55 ` Paul E. McKenney
2011-06-10 17:05 ` Matthew Garrett
2011-06-10 17:19 ` Paul E. McKenney
2011-06-10 17:23 ` Matthew Garrett
2011-06-10 17:52 ` Paul E. McKenney
2011-06-10 18:08 ` Matthew Garrett
2011-06-10 18:47 ` Paul E. McKenney
2011-06-10 19:23 ` Matthew Garrett
2011-06-10 19:37 ` Paul E. McKenney
2011-06-10 20:12 ` Matthew Garrett
2011-06-11 3:02 ` Arjan van de Ven
2011-06-11 17:06 ` Paul E. McKenney
2011-06-11 17:26 ` Arjan van de Ven
2011-06-12 23:07 ` Paul E. McKenney
2011-06-13 14:28 ` Arjan van de Ven
2011-06-13 23:04 ` Paul E. McKenney
2011-06-14 8:51 ` Ankita Garg
2011-06-15 16:53 ` Ankita Garg
2011-06-18 4:08 ` Arjan van de Ven
2011-06-10 17:33 ` Ankita Garg
2011-06-11 17:08 ` Paul E. McKenney
2011-07-12 5:31 ` amit kachhap
2011-06-13 4:47 ` KAMEZAWA Hiroyuki
2011-06-16 4:20 ` Ankita Garg
2011-06-16 9:12 ` KAMEZAWA Hiroyuki
2011-06-17 15:28 ` Ankita Garg [this message]
2011-06-19 23:53 ` KAMEZAWA Hiroyuki
2011-06-16 16:04 ` Dave Hansen
2011-06-17 10:03 ` Ankita Garg
2011-06-29 13:00 ` Ankita Garg
2011-06-29 17:06 ` Dave Hansen
2011-06-29 17:42 ` Ankita Garg
2011-06-29 17:59 ` Dave Hansen
2011-06-29 18:17 ` Vaidyanathan Srinivasan
2011-06-30 4:37 ` Ankita Garg
2011-06-29 20:11 ` Andi Kleen
2011-06-30 5:11 ` Ankita Garg
2011-06-29 18:07 ` Vaidyanathan Srinivasan
2011-07-06 8:45 ` Pekka Enberg
2011-07-06 9:01 ` Pekka Enberg
2011-07-06 16:50 ` Vaidyanathan Srinivasan
2011-07-06 16:41 ` Vaidyanathan Srinivasan
2011-07-06 20:20 ` david
2011-07-07 4:54 ` Ankita Garg
2011-07-07 18:00 ` Pekka Enberg
2011-07-08 1:32 ` david
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20110617152845.GA13574@in.ibm.com \
--to=ankita@in.ibm.com \
--cc=kamezawa.hiroyu@jp.fujitsu.com \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=linux-pm@lists.linux-foundation.org \
--cc=svaidy@linux.vnet.ibm.com \
--cc=thomas.abraham@linaro.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).