From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933867AbXLOAvl (ORCPT ); Fri, 14 Dec 2007 19:51:41 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754929AbXLOAvb (ORCPT ); Fri, 14 Dec 2007 19:51:31 -0500 Received: from nz-out-0506.google.com ([64.233.162.231]:27716 "EHLO nz-out-0506.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754440AbXLOAva (ORCPT ); Fri, 14 Dec 2007 19:51:30 -0500 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:date:from:to:subject:cc:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references; b=dL2AUhVcp2Oc7rCoV62L9hdvoUn4+bQp6qURMvqEaiScgDaKdQRlxE/KSayVzFgXUKf5fNXLVTfDdcaNiN/qC128JKOuyPkDeP4JwBCI2ZR3lL8ZpS7clhS6oDjI8qAJ9yk2VLVaV4HXbdWoPmBjpbpuSP7c4QO1O9SY2bQR/zM= Message-ID: <82e4877d0712141651j3965fd85ged2cefed5336e1ef@mail.gmail.com> Date: Fri, 14 Dec 2007 19:51:28 -0500 From: "Parag Warudkar" To: "Len Brown" Subject: Re: soft lockup - CPU#1 stuck for 15s! [swapper:0] Cc: "Thomas Gleixner" , "Arjan van de Ven" , "Ingo Molnar" , "Pallipadi, Venkatesh" , LKML , "Andrew Morton" , "Linus Torvalds" In-Reply-To: <200712141817.47581.lenb@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <924EFEDD5F540B4284297C4DC59F3DEE38C3C2@orsmsx423.amr.corp.intel.com> <82e4877d0712102049g4830a573n86b7f72f31a42f11@mail.gmail.com> <200712141817.47581.lenb@kernel.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Dec 14, 2007 6:17 PM, Len Brown wrote: > does processor.max_cstate=1 make the failing configuration work? > If yes, how about processor.max_cstate=2? Until now 2 things were necessary to reproduce the problem - 1) CPU_IDLE=y and 2) Wakeups from Idle = 5-7 Per second (== Longer/deeper C state residency) If I left the wakeups to high number (50-60) - there were no lockups but it was very jerky over ssh. (Typing keys had no effect for seconds etc.) CPU_IDLE=y With max_cstate=1 and CPU_IDLE=y things are pretty smooth - no lockups for the last hour. (Soft lockups used to appear in minutes previously.) With max_cstate=2 - old story repeats - it's very jerky and soft lockups appear in under a minute after going to 3-5 wakeups from idle per sec. > > what do you see in /proc/acpi/processor/*/power? > Normally (without any max_cstate= parameter) I see this - (I admit I never thought there was a C8 - C3 was all I ever heard.) [parag@mini router]$ cat /proc/acpi/processor/CPU0/power active state: C2 max_cstate: C8 bus master activity: 00000000 maximum allowed latency: 8000 usec states: C1: type[C1] promotion[C2] demotion[--] latency[001] usage[00001010] duration[00000000000000000000] *C2: type[C2] promotion[--] demotion[C1] latency[001] usage[07181700] duration[00000000379397304978] Thanks Parag