From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755804Ab0JWCNo (ORCPT ); Fri, 22 Oct 2010 22:13:44 -0400 Received: from mail-qy0-f181.google.com ([209.85.216.181]:54214 "EHLO mail-qy0-f181.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753028Ab0JWCNn (ORCPT ); Fri, 22 Oct 2010 22:13:43 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=date:from:to:cc:subject:message-id:references:mime-version :content-type:content-disposition:in-reply-to:user-agent; b=Qa3uC4U9jhJpg7h4+r3aTpd+WtLmFxlV5Ni/kxoKJGyq2/X2Itk7lQzF9s1t/cl9NK datcNhNHyBG8s6IUzm94XGTHVdETLyzvwTM205VLZJEjNxZaYERfmjBujESm7IZgVkek LEDstuVa1J99aLiNckZBJd0nv/g4iMi39GmXM= Date: Fri, 22 Oct 2010 22:13:38 -0400 From: tmhikaru@gmail.com To: Venkatesh Pallipadi Cc: Peter Zijlstra , Damien Wyart , Chase Douglas , Ingo Molnar , tmhikaru@gmail.com, Thomas Gleixner , linux-kernel@vger.kernel.org Subject: Re: High CPU load when machine is idle (related to PROBLEM: Unusually high load average when idle in 2.6.35, 2.6.35.1 and later) Message-ID: <20101023021338.GA8205@roll> References: <1287788622-25860-1-git-send-email-venki@google.com> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="BXVAT5kNtrzKuDFl" Content-Disposition: inline In-Reply-To: <1287788622-25860-1-git-send-email-venki@google.com> User-Agent: Mutt/1.4.2.3i Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --BXVAT5kNtrzKuDFl Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Fri, Oct 22, 2010 at 04:03:42PM -0700, Venkatesh Pallipadi wrote: > (Sorry about the subjectless earlier mail) >=20 > I started making small changes to the code, but none of the change helped= much. > I think the problem with the current code is that, even though idle CPUs > update load, the fold only happens when one of the CPU is busy > and we end up taking its load into global load. >=20 > So, I tried to simplify things and doing the updates directly from idle l= oop. > This is only a test patch, and eventually we need to hook it off somewhere > else, instead of idle loop and also this is expected work only as x86_64 > right now. >=20 > Peter: Do you think something like this will work? loadavg went > quite on two of my test systems after this change (4 cpu and 24 cpu). >=20 > Thanks, > Venki I'd really like to be able to help test this, but with a 32bit x86 machine I guess this patch won't do anything for me. How hard would it be to mangle this into working for my machine or should I just wait? Tim McGrath --BXVAT5kNtrzKuDFl Content-Type: application/pgp-signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.10 (GNU/Linux) iQEVAwUBTMJE0pEncCrqzVruAQIdngf9F8v8GocuBmyOr5JK62O/sD516hUzrM8/ s+KLJpGhuANylYkax7ESx3iGci5VvGfEKmH0iDU1mHEs11w3lFD0n392sGbK9mJf m7YpjAhXtp/phlYFDR7u1D+nrcxegDOET12qm6sXEVzhppdjMQ88AJPi2mAoBMIX LGw641kDn/BXboSHHhxzRaSIhH2oDVYxB9DgJBtFIx295cU10BBXmw1Fmo1yRUDF /hwgHdKR3c6sYpPBJGqR0rb1g1uv/rNHkJYOB/DYdyh1cDeMau0aVm6xPxsL2RRO D9Lcuvi6QWgqY9y7p70D+lu7zmUnjbLonEJTRmjBaimc1X37J2kN4A== =ApqI -----END PGP SIGNATURE----- --BXVAT5kNtrzKuDFl--