From owner-freebsd-bugs@FreeBSD.ORG Wed Jan 13 14:50:05 2010 Return-Path: Delivered-To: freebsd-bugs@hub.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 7541B1065672 for ; Wed, 13 Jan 2010 14:50:05 +0000 (UTC) (envelope-from gnats@FreeBSD.org) Received: from freefall.freebsd.org (freefall.freebsd.org [IPv6:2001:4f8:fff6::28]) by mx1.freebsd.org (Postfix) with ESMTP id 642C78FC08 for ; Wed, 13 Jan 2010 14:50:05 +0000 (UTC) Received: from freefall.freebsd.org (localhost [127.0.0.1]) by freefall.freebsd.org (8.14.3/8.14.3) with ESMTP id o0DEo5LB010381 for ; Wed, 13 Jan 2010 14:50:05 GMT (envelope-from gnats@freefall.freebsd.org) Received: (from gnats@localhost) by freefall.freebsd.org (8.14.3/8.14.3/Submit) id o0DEo5JA010380; Wed, 13 Jan 2010 14:50:05 GMT (envelope-from gnats) Date: Wed, 13 Jan 2010 14:50:05 GMT Message-Id: <201001131450.o0DEo5JA010380@freefall.freebsd.org> To: freebsd-bugs@FreeBSD.org From: Efstratios Karatzas Cc: Subject: Re: bin/136759: iostat(8) displays wrong I/O statistics with -c 1 X-BeenThere: freebsd-bugs@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list Reply-To: Efstratios Karatzas List-Id: Bug reports List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 13 Jan 2010 14:50:05 -0000 The following reply was made to PR bin/136759; it has been noted by GNATS. From: Efstratios Karatzas To: bug-followup@freebsd.org, vovets@gmail.com Cc: Subject: Re: bin/136759: iostat(8) displays wrong I/O statistics with -c 1 Date: Wed, 13 Jan 2010 16:40:48 +0200 Hi there, This is definitely not a bug. Take a look at the freebsd man page for iostat(8) http://www.freebsd.org/cgi/man.cgi?query=iostat&apropos=0&sektion=8&manpath=FreeBSD+8.0-RELEASE&format=html The manual clearly states that : "The first statistics that are printed are averaged over the system uptime. To get information about the current activity, a suitable wait time should be specified, so that the subsequent sets of printed statistics will be averaged over that time." So the first line of statistics always contains the "average statistics" since the system started running. If you want to get the statistics for the next 5 secs try something like iostat -c 6 -d some_device Hope this helps -- Efstratios "GPF" Karatzas