From mboxrd@z Thu Jan 1 00:00:00 1970 From: Yilong Li Subject: Re: Need help in tracking down OS jitters using Intel PT Date: Thu, 23 Mar 2017 12:56:41 -0700 Message-ID: References: <6ccea408-bf0e-e730-5375-e6cba55f6540@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Return-path: Received: from smtp2.cs.stanford.edu ([171.64.64.26]:47166 "EHLO smtp2.cs.Stanford.EDU" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751170AbdCWT4n (ORCPT ); Thu, 23 Mar 2017 15:56:43 -0400 Received: from mail-pg0-f48.google.com ([74.125.83.48]:35904) by smtp2.cs.Stanford.EDU with esmtpsa (TLSv1.2:ECDHE-RSA-AES128-GCM-SHA256:128) (Exim 4.88) (envelope-from ) id 1cr8qf-0003BS-LR for linux-perf-users@vger.kernel.org; Thu, 23 Mar 2017 12:56:42 -0700 Received: by mail-pg0-f48.google.com with SMTP id g2so128218242pge.3 for ; Thu, 23 Mar 2017 12:56:41 -0700 (PDT) In-Reply-To: <6ccea408-bf0e-e730-5375-e6cba55f6540@gmail.com> Sender: linux-perf-users-owner@vger.kernel.org List-ID: To: David Ahern Cc: "linux-perf-use." Thanks for the information! I didn't know that. I will give it a try. Yilong On Thu, Mar 23, 2017 at 8:30 AM, David Ahern wrote: > On 3/23/17 3:28 AM, Yilong Li wrote: >> What am I missing? Where does the 15us go? The program and the scripts >> I used in the experiment can be found here: >> https://github.com/yilongli/OSJitterTest. > > have you tried the hw latency detector? kernel/trace/trace_hwlat.c and > config HWLAT_TRACER