From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S936370Ab3DJM6O (ORCPT ); Wed, 10 Apr 2013 08:58:14 -0400 Received: from mail-ea0-f177.google.com ([209.85.215.177]:51980 "EHLO mail-ea0-f177.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932521Ab3DJM6N (ORCPT ); Wed, 10 Apr 2013 08:58:13 -0400 Date: Wed, 10 Apr 2013 14:58:08 +0200 From: Ingo Molnar To: Andi Kleen Cc: a.p.zijlstra@chello.nl, linux-kernel@vger.kernel.org, Andi Kleen Subject: Re: [PATCH] perf, x86: Allow setting period 1 Message-ID: <20130410125808.GC12978@gmail.com> References: <1362785070-12860-1-git-send-email-andi@firstfloor.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1362785070-12860-1-git-send-email-andi@firstfloor.org> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org * Andi Kleen wrote: > From: Andi Kleen > > I had some requests for setting period 1, so that every event of something > is caught. To my knowledge there is no limit to 1 on Intel hardware. > Just remove the check for minimum 2 > > If specific CPUs have problems we can black list them. How have you tested this? The commit that added this quirk mentions very high perf load triggering badness unless this quirk is added. Thanks, Ingo