All of lore.kernel.org
 help / color / mirror / Atom feed
From: Thomas Gleixner <tglx@linutronix.de>
To: Wanpeng Li <kernellwp@gmail.com>
Cc: LKML <linux-kernel@vger.kernel.org>,
	Ingo Molnar <mingo@kernel.org>,
	Peter Zijlstra <peterz@infradead.org>,
	Ingo Molnar <mingo@redhat.com>, kvm <kvm@vger.kernel.org>,
	Frederic Weisbecker <frederic@kernel.org>
Subject: Re: [PATCH v2] sched/nohz: Optimize get_nohz_timer_target()
Date: Wed, 23 Oct 2019 10:29:12 +0200 (CEST)	[thread overview]
Message-ID: <alpine.DEB.2.21.1910231028250.2308@nanos.tec.linutronix.de> (raw)
In-Reply-To: <CANRm+CxUpwZ9KwOcQp=Ok64giyjjcJOGb2=zU6vayQzLqYvpXQ@mail.gmail.com>

On Wed, 23 Oct 2019, Wanpeng Li wrote:
> I didn't see your refactor to get_nohz_timer_target() which you
> mentioned in IRC after four months, I can observe cyclictest drop from
> 4~5us to 8us in kvm guest(we offload the lapic timer emulation to
> housekeeping cpu to avoid timer fire external interrupt on the pCPU
> which vCPU resident incur a vCPU vmexit) w/o this patch in the case of
> there is no busy housekeeping cpu. The score can be recovered after I
> give stress to create a busy housekeeping cpu.
> 
> Could you consider applying this patch for temporary since I'm not
> sure when the refactor can be ready.

Yeah. It's delayed (again).... Will pick that up.

Thanks,

	tglx

  reply	other threads:[~2019-10-23  8:29 UTC|newest]

Thread overview: 13+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-06-28  0:43 [PATCH v2] sched/nohz: Optimize get_nohz_timer_target() Wanpeng Li
2019-06-28  0:43 ` [PATCH RESEND v3] sched/isolation: Prefer housekeeping cpu in local node Wanpeng Li
2019-06-28  1:18   ` Frederic Weisbecker
2019-06-28  6:58   ` Srikar Dronamraju
2019-06-28  7:19     ` Wanpeng Li
2019-06-28  8:44       ` Srikar Dronamraju
2019-06-28  1:10 ` [PATCH v2] sched/nohz: Optimize get_nohz_timer_target() Frederic Weisbecker
2019-10-23  8:16   ` Wanpeng Li
2019-10-23  8:29     ` Thomas Gleixner [this message]
2019-10-23  9:25       ` Wanpeng Li
2020-01-06  6:21       ` Wanpeng Li
2020-01-10 14:12         ` Thomas Gleixner
2020-01-13  1:32           ` Wanpeng Li

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=alpine.DEB.2.21.1910231028250.2308@nanos.tec.linutronix.de \
    --to=tglx@linutronix.de \
    --cc=frederic@kernel.org \
    --cc=kernellwp@gmail.com \
    --cc=kvm@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mingo@kernel.org \
    --cc=mingo@redhat.com \
    --cc=peterz@infradead.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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.