From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 22328 invoked by alias); 6 Oct 2006 00:00:31 -0000 Received: (qmail 22320 invoked by uid 22791); 6 Oct 2006 00:00:31 -0000 X-Spam-Status: No, hits=-1.2 required=5.0 tests=AWL,BAYES_00,SPF_HELO_PASS,SPF_PASS,UNPARSEABLE_RELAY X-Spam-Check-By: sourceware.org Received: from mx1.redhat.com (HELO mx1.redhat.com) (66.187.233.31) by sourceware.org (qpsmtpd/0.31) with ESMTP; Fri, 06 Oct 2006 00:00:26 +0000 Received: from int-mx1.corp.redhat.com (int-mx1.corp.redhat.com [172.16.52.254]) by mx1.redhat.com (8.12.11.20060308/8.12.11) with ESMTP id k9600OdY019649; Thu, 5 Oct 2006 20:00:24 -0400 Received: from pobox.toronto.redhat.com (pobox.toronto.redhat.com [172.16.14.4]) by int-mx1.corp.redhat.com (8.12.11.20060308/8.12.11) with ESMTP id k9600NXv011095; Thu, 5 Oct 2006 20:00:23 -0400 Received: from touchme.toronto.redhat.com (IDENT:postfix@touchme.toronto.redhat.com [172.16.14.9]) by pobox.toronto.redhat.com (8.12.8/8.12.8) with ESMTP id k9600NY7025610; Thu, 5 Oct 2006 20:00:23 -0400 Received: from ton.toronto.redhat.com (ton.toronto.redhat.com [172.16.14.15]) by touchme.toronto.redhat.com (Postfix) with ESMTP id 5DD73800002; Thu, 5 Oct 2006 20:00:23 -0400 (EDT) Received: from ton.toronto.redhat.com (localhost.localdomain [127.0.0.1]) by ton.toronto.redhat.com (8.13.1/8.13.1) with ESMTP id k9600Nud032404; Thu, 5 Oct 2006 20:00:23 -0400 Received: (from fche@localhost) by ton.toronto.redhat.com (8.13.1/8.13.1/Submit) id k9600NrJ032403; Thu, 5 Oct 2006 20:00:23 -0400 Date: Fri, 06 Oct 2006 00:00:00 -0000 From: "Frank Ch. Eigler" To: Mike Mason Cc: systemtap@sources.redhat.com Subject: Re: Fwd: Any way to find the network usage by a process? Message-ID: <20061006000023.GA24096@redhat.com> References: <3420082f0610030114o5b44b8ak7797483e02002614@mail.gmail.com> <3420082f0610030114o4c6998en907bccce81d28c59@mail.gmail.com> <452285FD.7010909@us.ibm.com> <45241F7A.5050501@us.ibm.com> <4525950A.8020009@us.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4525950A.8020009@us.ibm.com> User-Agent: Mutt/1.4.1i Mailing-List: contact systemtap-help@sourceware.org; run by ezmlm Precedence: bulk List-Subscribe: List-Post: List-Help: , Sender: systemtap-owner@sourceware.org X-SW-Source: 2006-q4/txt/msg00032.txt.bz2 Hi - On Thu, Oct 05, 2006 at 04:28:10PM -0700, Mike Mason wrote: > [...] > ERROR: empty aggregate near identifier 'execname' at nettop.stp:35:4 > WARNING: Number of errors: 1, skipped probes: 0 > Apparently using @sum on empty aggregates isn't allowed. I expected 0's to > be returned. As a judgement call, to be consistent with other extractors like @avg, the @sum etc. of an empty set was deemed to be undefined. > The only way to avoid the error is use @sum only if @count > > 0, which makes the printf too complex in my opinion. Maybe so. It's worth considering some syntactic sugar to express a undefined=>0 intent. > >The way that the script tracks pid-to-uid and pid-to-execname mappings > >is not bad, though if that part were moved to new probes on fork or > >exec, it would allow the network-related probes to run concurrently on > >an SMP without fighting over locks. > > But that would only catch processes created after the script starts, > correct? That's true. - FChE