LKML Archive on
help / color / mirror / Atom feed
From: Arjan van de Ven <>
	Linux-pm mailing list <>,
	Linux Kernel <>,
	Dipankar Sarma <>, Ingo Molnar <>,,,, Gautham R Shenoy <>,
	Chanda Sethia <>
Subject: Re: Too many timer interrupts in NO_HZ
Date: Sun, 2 Mar 2008 11:57:09 -0800	[thread overview]
Message-ID: <> (raw)
In-Reply-To: <>

On Mon, 3 Mar 2008 01:18:13 +0530
Vaidyanathan Srinivasan <> wrote:

> Hi,
> I am trying to play around with the tickless kernel and
> sched_mc_power_savings tunables to increase the idle duration of the
> CPU in an SMP server.  sched_mc_power_savings provides good
> consolidation of long running jobs when the system is lightly loaded.
> However I am interested to see CPU idle times for couple minutes on
> atleast few CPUs in an completely idle SMP system.
> I have posted related instrumentation results at
> The experimental setup is identical.  Just that I have tried to
> collect more data and also bias the wakeup logic.
> The kernel is 2.6.25-rc3 with NO_HZ, SCHED_MC, HIGH_RES_TIMERS, and
> HPET turned on.
> I have tried to collect interesting data from tick-sched.c, sched.c
> and softirq.c.
> As suggested by Ingo in the previous thread, I have hacked the sched.c
> try_to_wake_up logic so that I can force all wake-ups to happen on
> CPU0.  This is just and experiment, in reality we will have to
> carefully choose a domain and CPU to bias all wakeups on an idle
> system.

please show us powertop -d output; that way we can at least see sort of what
is going on...

  reply	other threads:[~2008-03-02 19:58 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2008-03-02 19:48 Vaidyanathan Srinivasan
2008-03-02 19:57 ` Arjan van de Ven [this message]
2008-03-02 20:25   ` Vaidyanathan Srinivasan
2008-03-05 15:38   ` Vaidyanathan Srinivasan
2008-03-16 18:17 ` Vaidyanathan Srinivasan
2008-03-17  2:34   ` [linux-pm] " Alan Stern
2008-03-17  8:44     ` David Brownell

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:

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \ \ \ \ \ \ \ \ \ \ \ \ \ \
    --subject='Re: Too many timer interrupts in NO_HZ' \

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

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).