From owner-freebsd-hackers@FreeBSD.ORG Fri Apr 11 08:57:55 2003 Return-Path: Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 36CE537B401; Fri, 11 Apr 2003 08:57:55 -0700 (PDT) Received: from heron.mail.pas.earthlink.net (heron.mail.pas.earthlink.net [207.217.120.189]) by mx1.FreeBSD.org (Postfix) with ESMTP id 961D643F75; Fri, 11 Apr 2003 08:57:54 -0700 (PDT) (envelope-from tlambert2@mindspring.com) Received: from pool0023.cvx40-bradley.dialup.earthlink.net ([216.244.42.23] helo=mindspring.com) by heron.mail.pas.earthlink.net with asmtp (SSLv3:RC4-MD5:128) (Exim 3.33 #1) id 1940uW-0005tk-00; Fri, 11 Apr 2003 08:57:52 -0700 Message-ID: <3E96E5AE.548EBC6@mindspring.com> Date: Fri, 11 Apr 2003 08:56:30 -0700 From: Terry Lambert X-Mailer: Mozilla 4.79 [en] (Win98; U) X-Accept-Language: en MIME-Version: 1.0 To: Peter Jeremy References: <20030411060823.GA27575@titan.klemm.apsfilter.org> <20030411080102.GC47320@cirb503493.alcatel.com.au> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-ELNK-Trace: b1a02af9316fbb217a47c185c03b154d40683398e744b8a42cf4e1d083019246230a69956fe75a2a667c3043c0873f7e350badd9bab72f9c350badd9bab72f9c cc: freebsd-hackers@freebsd.org Subject: Re: Solaris 2.x compat. system accounting, sarcheck for fbsd(commercial) X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 11 Apr 2003 15:57:55 -0000 Peter Jeremy wrote: > On Fri, Apr 11, 2003 at 08:08:23AM +0200, Andreas Klemm wrote: > >I wrote some performance monitoring utilities and need for > >example a parameter wait for I/O, that I didn't find in our > >tools, did I overlook something ? > > "wait for I/O" is a System-V state that BSD doesn't measure. > One of the grey[er] beards may be able to answer why SysV does > and BSD doesn't consider "wait for I/O" a state worth measuring. It is a state equal to "idle", with I/O requests pending completion. The intent is to say "I would be running some process X, but I'm idle because I'm waiting for I/O". Part of the problem in reporting this in FreeBSD is the inability to attribute pending I/O requests e.g. as the result of a fault by a process or as a result of a fault by the kernel itself. This is an artifact of the unified VM and buffer cache. -- Terry