From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Mon, 20 May 2002 01:22:23 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Mon, 20 May 2002 01:22:22 -0400 Received: from violet.setuza.cz ([194.149.118.97]:39180 "EHLO violet.setuza.cz") by vger.kernel.org with ESMTP id ; Mon, 20 May 2002 01:22:21 -0400 Subject: Re: counters From: Frank Schaefer To: linux-kernel@vger.kernel.org In-Reply-To: <20020517075235.A1680@p3.attbi.com> Content-Type: text/plain Content-Transfer-Encoding: 7bit X-Mailer: Evolution/1.0 (Preview Release) Date: 20 May 2002 07:22:22 +0200 Message-Id: <1021872142.250.5.camel@ADMIN> Mime-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org that's right, but it would give one a picture how much a process --let's say-- requests I/O. Regards Frank On Fri, 2002-05-17 at 16:52, Jerry Cooperstein wrote: > This is doable (some other OS's do it) but: > > 1) It requires some changes to the basic read/write call to gather > the statistics. It also requires stashing the counters somewhere > such as in the task_struct and thus requires modifying it. > > 2) It doesn't directly tell you about I/O statistics themselves > (which are available under /proc/stat) because the I/O request > may be gotten from cache, or may never be flushed from cache > to disk depending on subsequent events, so it will always > tend to overestimate the amount of real I/O done on the device. > > Jerry Cooperstein > Axian, Inc. Software Consulting and Training > 4800 SW Griffith Dr., Ste. 202, Beaverton, OR 97005 USA > http://www.axian.com/ > > > On Thu, May 16, 2002 at 07:44:35PM +0530, Manik Raina wrote: > > anyone knows if there are counters in the linux kernel > > which can be read via /proc like mechanism for the > > following : > > > > 1. total number of bytes read by process by syscalls > > like read() > > > > 2. total number of bytes written by each process by > > syscalls like write() > > > > thanks > > - > - > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/ >