linux-pm.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: "Srivatsa S. Bhat" <srivatsa.bhat@linux.vnet.ibm.com>
To: Arjan van de Ven <arjan@linux.intel.com>
Cc: Andi Kleen <andi@firstfloor.org>,
	Andrew Morton <akpm@linux-foundation.org>,
	mgorman@suse.de, dave@sr71.net, hannes@cmpxchg.org,
	tony.luck@intel.com, matthew.garrett@nebula.com, riel@redhat.com,
	srinivas.pandruvada@linux.intel.com, willy@linux.intel.com,
	kamezawa.hiroyu@jp.fujitsu.com, lenb@kernel.org, rjw@sisk.pl,
	gargankita@gmail.com, paulmck@linux.vnet.ibm.com,
	svaidy@linux.vnet.ibm.com, isimatu.yasuaki@jp.fujitsu.com,
	santosh.shilimkar@ti.com, kosaki.motohiro@gmail.com,
	linux-pm@vger.kernel.org, linux-mm@kvack.org,
	linux-kernel@vger.kernel.org, maxime.coquelin@stericsson.com,
	loic.pallardy@stericsson.com, thomas.abraham@linaro.org,
	amit.kachhap@linaro.org
Subject: Re: [Results] [RFC PATCH v4 00/40] mm: Memory Power Management
Date: Thu, 26 Sep 2013 18:39:19 +0530	[thread overview]
Message-ID: <524431FF.50904@linux.vnet.ibm.com> (raw)
In-Reply-To: <52438A6B.30202@linux.intel.com>

On 09/26/2013 06:44 AM, Arjan van de Ven wrote:
> On 9/25/2013 4:47 PM, Andi Kleen wrote:
>>> Also, the changelogs don't appear to discuss one obvious downside: the
>>> latency incurred in bringing a bank out of one of the low-power states
>>> and back into full operation.  Please do discuss and quantify that to
>>> the best of your knowledge.
>>
>> On Sandy Bridge the memry wakeup overhead is really small. It's on by
>> default
>> in most setups today.
> 
> yet grouping is often defeated (in current systems) due to hw level
> interleaving ;-(
> sometimes that's a bios setting though.
> 

True, and I plan to tweak those hardware settings in the prototype powerpc
platform and evaluate the power vs performance trade-offs of various
interleaving schemes in conjunction with this patchset.

> in internal experimental bioses we've been able to observe a "swing" of
> a few watts
> (not with these patches but with some other tricks)...

Great! So, would you have the opportunity to try out this patchset as well
on those systems that you have? I can modify the patchset to take memory
region info from whatever source you want me to take it from and then we'll
have realistic power-savings numbers to evaluate this patchset and its benefits
on Intel/x86 platforms.

> I'm curious to see how these patches do for Srivatsa
> 

As I mentioned in my other mail, I don't yet have a setup for doing actual
power-measurements. Hence, so far I was focussing on the algorithmic aspects
of the patchset and was trying to get an excellent consolidation ratio,
without hurting performance too much. Going forward, I'll work on getting the
power-measurements as well on the powerpc platform that I have.
 
Regards,
Srivatsa S. Bhat


  reply	other threads:[~2013-09-26 13:13 UTC|newest]

Thread overview: 77+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-09-25 23:13 [RFC PATCH v4 00/40] mm: Memory Power Management Srivatsa S. Bhat
2013-09-25 23:13 ` [RFC PATCH v4 01/40] mm: Introduce memory regions data-structure to capture region boundaries within nodes Srivatsa S. Bhat
2013-10-23  9:54   ` Johannes Weiner
2013-10-23 14:38     ` Srivatsa S. Bhat
2013-09-25 23:14 ` [RFC PATCH v4 02/40] mm: Initialize node memory regions during boot Srivatsa S. Bhat
2013-09-25 23:14 ` [RFC PATCH v4 03/40] mm: Introduce and initialize zone memory regions Srivatsa S. Bhat
2013-09-25 23:14 ` [RFC PATCH v4 04/40] mm: Add helpers to retrieve node region and zone region for a given page Srivatsa S. Bhat
2013-09-25 23:14 ` [RFC PATCH v4 05/40] mm: Add data-structures to describe memory regions within the zones' freelists Srivatsa S. Bhat
2013-09-25 23:14 ` [RFC PATCH v4 06/40] mm: Demarcate and maintain pageblocks in region-order in " Srivatsa S. Bhat
2013-09-26 22:16   ` Dave Hansen
2013-09-27  6:34     ` Srivatsa S. Bhat
2013-10-23 10:17   ` Johannes Weiner
2013-10-23 16:09     ` Srivatsa S. Bhat
2013-09-25 23:15 ` [RFC PATCH v4 07/40] mm: Track the freepage migratetype of pages accurately Srivatsa S. Bhat
2013-09-25 23:15 ` [RFC PATCH v4 08/40] mm: Use the correct migratetype during buddy merging Srivatsa S. Bhat
2013-09-25 23:15 ` [RFC PATCH v4 09/40] mm: Add an optimized version of del_from_freelist to keep page allocation fast Srivatsa S. Bhat
2013-09-25 23:15 ` [RFC PATCH v4 10/40] bitops: Document the difference in indexing between fls() and __fls() Srivatsa S. Bhat
2013-09-25 23:16 ` [RFC PATCH v4 11/40] mm: A new optimized O(log n) sorting algo to speed up buddy-sorting Srivatsa S. Bhat
2013-09-25 23:16 ` [RFC PATCH v4 12/40] mm: Add support to accurately track per-memory-region allocation Srivatsa S. Bhat
2013-09-25 23:16 ` [RFC PATCH v4 13/40] mm: Print memory region statistics to understand the buddy allocator behavior Srivatsa S. Bhat
2013-09-25 23:17 ` [RFC PATCH v4 14/40] mm: Enable per-memory-region fragmentation stats in pagetypeinfo Srivatsa S. Bhat
2013-09-25 23:17 ` [RFC PATCH v4 15/40] mm: Add aggressive bias to prefer lower regions during page allocation Srivatsa S. Bhat
2013-09-25 23:17 ` [RFC PATCH v4 16/40] mm: Introduce a "Region Allocator" to manage entire memory regions Srivatsa S. Bhat
2013-10-23 10:10   ` Johannes Weiner
2013-10-23 16:22     ` Srivatsa S. Bhat
2013-09-25 23:17 ` [RFC PATCH v4 17/40] mm: Add a mechanism to add pages to buddy freelists in bulk Srivatsa S. Bhat
2013-09-25 23:18 ` [RFC PATCH v4 18/40] mm: Provide a mechanism to delete pages from " Srivatsa S. Bhat
2013-09-25 23:18 ` [RFC PATCH v4 19/40] mm: Provide a mechanism to release free memory to the region allocator Srivatsa S. Bhat
2013-09-25 23:18 ` [RFC PATCH v4 20/40] mm: Provide a mechanism to request free memory from " Srivatsa S. Bhat
2013-09-25 23:18 ` [RFC PATCH v4 21/40] mm: Maintain the counter for freepages in " Srivatsa S. Bhat
2013-09-25 23:18 ` [RFC PATCH v4 22/40] mm: Propagate the sorted-buddy bias for picking free regions, to " Srivatsa S. Bhat
2013-09-25 23:19 ` [RFC PATCH v4 23/40] mm: Fix vmstat to also account for freepages in the " Srivatsa S. Bhat
2013-09-25 23:19 ` [RFC PATCH v4 24/40] mm: Drop some very expensive sorted-buddy related checks under DEBUG_PAGEALLOC Srivatsa S. Bhat
2013-09-25 23:19 ` [RFC PATCH v4 25/40] mm: Connect Page Allocator(PA) to Region Allocator(RA); add PA => RA flow Srivatsa S. Bhat
2013-09-25 23:19 ` [RFC PATCH v4 26/40] mm: Connect Page Allocator(PA) to Region Allocator(RA); add PA <= " Srivatsa S. Bhat
2013-09-25 23:19 ` [RFC PATCH v4 27/40] mm: Update the freepage migratetype of pages during region allocation Srivatsa S. Bhat
2013-09-25 23:20 ` [RFC PATCH v4 28/40] mm: Provide a mechanism to check if a given page is in the region allocator Srivatsa S. Bhat
2013-09-25 23:20 ` [RFC PATCH v4 29/40] mm: Add a way to request pages of a particular region from " Srivatsa S. Bhat
2013-09-25 23:20 ` [RFC PATCH v4 30/40] mm: Modify move_freepages() to handle pages in the region allocator properly Srivatsa S. Bhat
2013-09-25 23:20 ` [RFC PATCH v4 31/40] mm: Never change migratetypes of pageblocks during freepage stealing Srivatsa S. Bhat
2013-09-25 23:20 ` [RFC PATCH v4 32/40] mm: Set pageblock migratetype when allocating regions from region allocator Srivatsa S. Bhat
2013-09-25 23:21 ` [RFC PATCH v4 33/40] mm: Use a cache between page-allocator and region-allocator Srivatsa S. Bhat
2013-09-25 23:21 ` [RFC PATCH v4 34/40] mm: Restructure the compaction part of CMA for wider use Srivatsa S. Bhat
2013-09-25 23:21 ` [RFC PATCH v4 35/40] mm: Add infrastructure to evacuate memory regions using compaction Srivatsa S. Bhat
2013-09-25 23:21 ` [RFC PATCH v4 36/40] kthread: Split out kthread-worker bits to avoid circular header-file dependency Srivatsa S. Bhat
2013-09-25 23:22 ` [RFC PATCH v4 37/40] mm: Add a kthread to perform targeted compaction for memory power management Srivatsa S. Bhat
2013-09-25 23:22 ` [RFC PATCH v4 38/40] mm: Add a mechanism to queue work to the kmempowerd kthread Srivatsa S. Bhat
2013-09-25 23:22 ` [RFC PATCH v4 39/40] mm: Add intelligence in kmempowerd to ignore regions unsuitable for evacuation Srivatsa S. Bhat
2013-09-25 23:22 ` [RFC PATCH v4 40/40] mm: Add triggers in the page-allocator to kick off region evacuation Srivatsa S. Bhat
2013-09-25 23:26 ` [Results] [RFC PATCH v4 00/40] mm: Memory Power Management Srivatsa S. Bhat
2013-09-25 23:40   ` Andrew Morton
2013-09-25 23:47     ` Andi Kleen
2013-09-26  1:14       ` Arjan van de Ven
2013-09-26 13:09         ` Srivatsa S. Bhat [this message]
2013-09-26  1:15       ` Arjan van de Ven
2013-09-26  1:21         ` Andrew Morton
2013-09-26  1:50           ` Andi Kleen
2013-09-26  2:59             ` Andrew Morton
2013-09-26 13:42               ` Srivatsa S. Bhat
2013-09-26 15:58                 ` Arjan van de Ven
2013-09-26 17:00                   ` Srivatsa S. Bhat
2013-09-26 18:06                     ` Arjan van de Ven
2013-09-26 18:33                       ` Srivatsa S. Bhat
2013-09-26 18:50                         ` Luck, Tony
2013-09-26 18:56                           ` Srivatsa S. Bhat
2013-09-26 13:37             ` Srivatsa S. Bhat
2013-09-26 15:23           ` Arjan van de Ven
2013-09-26 13:16         ` Srivatsa S. Bhat
2013-09-26 12:58     ` Srivatsa S. Bhat
2013-09-26 15:29       ` Arjan van de Ven
2013-09-26 17:22       ` Luck, Tony
2013-09-26 17:54         ` Srivatsa S. Bhat
2013-09-26 19:38         ` Andi Kleen
2013-11-12  8:02       ` Srivatsa S. Bhat
2013-11-12 17:34         ` Dave Hansen
2013-11-12 18:44           ` Srivatsa S. Bhat
2013-11-12 18:49         ` Srivatsa S. Bhat

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=524431FF.50904@linux.vnet.ibm.com \
    --to=srivatsa.bhat@linux.vnet.ibm.com \
    --cc=akpm@linux-foundation.org \
    --cc=amit.kachhap@linaro.org \
    --cc=andi@firstfloor.org \
    --cc=arjan@linux.intel.com \
    --cc=dave@sr71.net \
    --cc=gargankita@gmail.com \
    --cc=hannes@cmpxchg.org \
    --cc=isimatu.yasuaki@jp.fujitsu.com \
    --cc=kamezawa.hiroyu@jp.fujitsu.com \
    --cc=kosaki.motohiro@gmail.com \
    --cc=lenb@kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=linux-pm@vger.kernel.org \
    --cc=loic.pallardy@stericsson.com \
    --cc=matthew.garrett@nebula.com \
    --cc=maxime.coquelin@stericsson.com \
    --cc=mgorman@suse.de \
    --cc=paulmck@linux.vnet.ibm.com \
    --cc=riel@redhat.com \
    --cc=rjw@sisk.pl \
    --cc=santosh.shilimkar@ti.com \
    --cc=srinivas.pandruvada@linux.intel.com \
    --cc=svaidy@linux.vnet.ibm.com \
    --cc=thomas.abraham@linaro.org \
    --cc=tony.luck@intel.com \
    --cc=willy@linux.intel.com \
    /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).