From mboxrd@z Thu Jan 1 00:00:00 1970 From: Vince Weaver Subject: Re: Sampling hardware counter values with timers Date: Fri, 13 May 2016 13:42:52 -0400 (EDT) Message-ID: References: <87vb2ikrdy.fsf@tassilo.jf.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Return-path: Received: from mail-io0-f179.google.com ([209.85.223.179]:35568 "EHLO mail-io0-f179.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751573AbcEMRnC (ORCPT ); Fri, 13 May 2016 13:43:02 -0400 Received: by mail-io0-f179.google.com with SMTP id d62so141705612iof.2 for ; Fri, 13 May 2016 10:43:02 -0700 (PDT) In-Reply-To: Sender: linux-perf-users-owner@vger.kernel.org List-ID: To: Keno Fischer Cc: Andi Kleen , linux-perf-users@vger.kernel.org On Fri, 13 May 2016, Keno Fischer wrote: > Thanks. I know that perf sample works this way, but I didn't think it > was possible to have it sample a specified counter. Is it? `perf stat > -I` looks exactly like what I need, but it looks like the maximum > frequency is 10Hz. I was hoping for a higher frequency (& ideally > something that > doesn't require switching back into user space and calling `read`). you can easily hack perf -I to sample faster than 10Hz, but if you sample much more often than that you're going to start ending up with a lot of perf_event measurement overhead in your data. Vince