From: Steven Rostedt <rostedt@goodmis.org>
To: paulmck@linux.vnet.ibm.com
Cc: Viresh Kumar <viresh.kumar@linaro.org>,
pjt@google.com, paul.mckenney@linaro.org, tglx@linutronix.de,
tj@kernel.org, suresh.b.siddha@intel.com, venki@google.com,
mingo@redhat.com, peterz@infradead.org, Arvind.Chauhan@arm.com,
linaro-dev@lists.linaro.org, patches@linaro.org,
pdsw-power-team@arm.com, linux-kernel@vger.kernel.org,
linux-rt-users@vger.kernel.org
Subject: Re: [PATCH V2 Resend 0/4] Create sched_select_cpu() and use it for workqueues and timers
Date: Mon, 26 Nov 2012 12:35:52 -0500 [thread overview]
Message-ID: <1353951352.6276.43.camel@gandalf.local.home> (raw)
In-Reply-To: <20121126170358.GE2474@linux.vnet.ibm.com>
On Mon, 2012-11-26 at 09:03 -0800, Paul E. McKenney wrote:
> If I understand correctly (though also suffering turkey OD), the idea is
> to offload work to more energy-efficient CPUs.
This is determined by a CPU that isn't running the idle task? Is it
because a CPU that just woke up may be running at a lower freq, and thus
not as efficient? But pushing off to another CPU may cause cache misses
as well. Wouldn't that also be a factor in efficiencies, if a CPU is
stalled waiting for memory to be loaded?
I should also ask the obvious. Has these patches shown real world
efficiencies or is this just a theory? Do these patches actually improve
battery life when applied?
Just asking.
-- Steve
next prev parent reply other threads:[~2012-11-26 17:35 UTC|newest]
Thread overview: 48+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-11-06 10:34 [PATCH V2 Resend 0/4] Create sched_select_cpu() and use it for workqueues and timers Viresh Kumar
[not found] ` <cover.1352196505.git.viresh.kumar-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>
2012-11-06 10:38 ` [PATCH V2 Resend 1/4] sched: Create sched_select_cpu() to give preferred CPU for power saving Viresh Kumar
2012-11-06 10:38 ` [PATCH V2 Resend 2/4] timer: hrtimer: Don't check idle_cpu() before calling get_nohz_timer_target() Viresh Kumar
2012-11-06 10:38 ` [PATCH V2 Resend 4/4] timer: Migrate running timer Viresh Kumar
2012-11-27 13:47 ` Steven Rostedt
2013-03-20 15:13 ` Viresh Kumar
2013-04-09 14:52 ` Viresh Kumar
2013-04-24 11:22 ` Viresh Kumar
2013-05-13 9:19 ` Viresh Kumar
2013-05-13 10:35 ` Thomas Gleixner
2013-05-22 8:34 ` Viresh Kumar
2013-05-22 9:06 ` Peter Zijlstra
2013-05-22 9:23 ` Viresh Kumar
2013-05-31 10:49 ` Viresh Kumar
2013-06-18 4:51 ` Viresh Kumar
2013-07-24 9:17 ` Viresh Kumar
2013-08-07 9:55 ` Viresh Kumar
2013-10-04 12:39 ` Sebastian Andrzej Siewior
2013-10-23 5:55 ` Viresh Kumar
2012-11-06 10:38 ` [PATCH V2 Resend 3/4] workqueue: Schedule work on non-idle cpu instead of current one Viresh Kumar
[not found] ` <ad25c731a6ca1bd1269555245952f05c856a9759.1352196505.git.viresh.kumar-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>
2012-11-26 17:15 ` Tejun Heo
2012-11-27 5:19 ` Viresh Kumar
2012-11-27 12:54 ` Vincent Guittot
[not found] ` <CAKohpom9=K976NmyFWtXx2UQyRcLAqsoGw-5AaqXRpSL6uxP_g-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2013-01-04 11:11 ` Viresh Kumar
2013-01-04 15:09 ` Tejun Heo
2013-01-07 9:58 ` Viresh Kumar
2013-01-07 13:28 ` Steven Rostedt
2013-01-07 17:59 ` Viresh Kumar
2013-01-07 22:29 ` Steven Rostedt
2013-01-08 4:03 ` Viresh Kumar
2013-01-07 15:04 ` Tejun Heo
2013-01-07 15:40 ` Amit Kucheria
2013-01-07 18:07 ` Viresh Kumar
2013-01-09 18:49 ` Tejun Heo
2013-01-10 5:04 ` Viresh Kumar
2012-11-27 13:26 ` Steven Rostedt
2012-11-27 13:48 ` Viresh Kumar
2012-11-27 13:59 ` Steven Rostedt
2012-11-27 14:55 ` Vincent Guittot
2012-11-27 15:04 ` Steven Rostedt
2012-11-27 15:35 ` Vincent Guittot
2012-11-26 15:00 ` [PATCH V2 Resend 0/4] Create sched_select_cpu() and use it for workqueues and timers Viresh Kumar
2012-11-26 16:40 ` Steven Rostedt
[not found] ` <1353948027.6276.38.camel-f9ZlEuEWxVcJvu8Pb33WZ0EMvNT87kid@public.gmane.org>
2012-11-26 17:03 ` Paul E. McKenney
2012-11-26 17:35 ` Steven Rostedt [this message]
[not found] ` <1353951352.6276.43.camel-f9ZlEuEWxVcJvu8Pb33WZ0EMvNT87kid@public.gmane.org>
2012-11-26 19:03 ` Paul E. McKenney
2012-11-26 19:17 ` Steven Rostedt
2012-11-27 6:25 ` Viresh Kumar
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=1353951352.6276.43.camel@gandalf.local.home \
--to=rostedt@goodmis.org \
--cc=Arvind.Chauhan@arm.com \
--cc=linaro-dev@lists.linaro.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-rt-users@vger.kernel.org \
--cc=mingo@redhat.com \
--cc=patches@linaro.org \
--cc=paul.mckenney@linaro.org \
--cc=paulmck@linux.vnet.ibm.com \
--cc=pdsw-power-team@arm.com \
--cc=peterz@infradead.org \
--cc=pjt@google.com \
--cc=suresh.b.siddha@intel.com \
--cc=tglx@linutronix.de \
--cc=tj@kernel.org \
--cc=venki@google.com \
--cc=viresh.kumar@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).