From mboxrd@z Thu Jan 1 00:00:00 1970 From: Arnaldo Carvalho de Melo Subject: Re: observations at periodic intervals Date: Mon, 9 Nov 2015 12:00:16 -0300 Message-ID: <20151109150016.GB4715@kernel.org> References: Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: Received: from mail.kernel.org ([198.145.29.136]:38488 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751462AbbKIPAV (ORCPT ); Mon, 9 Nov 2015 10:00:21 -0500 Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 495C7205ED for ; Mon, 9 Nov 2015 15:00:19 +0000 (UTC) Received: from zoo.infradead.org (unknown [179.235.152.54]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 89BD9205DF for ; Mon, 9 Nov 2015 15:00:18 +0000 (UTC) Content-Disposition: inline In-Reply-To: Sender: linux-perf-users-owner@vger.kernel.org List-ID: To: =?iso-8859-1?Q?Jos=E9_Sim=E3o?= Cc: linux-perf-users@vger.kernel.org Em Fri, Nov 06, 2015 at 09:06:14PM +0000, Jos=E9 Sim=E3o escreveu: > Dear user of linux-perf-users@vger.kernel.org, >=20 > When using the -I option of 'stat' to periodically collect the value > of performance counters (e.g. perf stat -e cache-misses -I 500 cmd) > the reported value at each internal (500ms in the example) is how muc= h > the selected counter increased since the last observation? >=20 > I assume it is because the values are not monotonically increasing. =46rom 'perf stat --help' /-I -I msecs, --interval-print msecs Print count deltas every N milliseconds (minimum: 100ms) example: perf stat -I 1000 -e cycles -a sleep 5 This is also available via 'man perf-stat' So, yes, your observation is correct, those are deltas. - Arnaldo