From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 16129 invoked by alias); 11 Aug 2010 16:19:12 -0000 Received: (qmail 16120 invoked by uid 22791); 11 Aug 2010 16:19:11 -0000 X-SWARE-Spam-Status: No, hits=-5.5 required=5.0 tests=AWL,BAYES_00,RCVD_IN_DNSWL_HI,SPF_HELO_PASS,TW_QE,T_RP_MATCHES_RCVD X-Spam-Check-By: sourceware.org Received: from mx1.redhat.com (HELO mx1.redhat.com) (209.132.183.28) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Wed, 11 Aug 2010 16:19:05 +0000 Received: from int-mx08.intmail.prod.int.phx2.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.21]) by mx1.redhat.com (8.13.8/8.13.8) with ESMTP id o7BGJ0dS016588 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Wed, 11 Aug 2010 12:19:00 -0400 Received: from fche.csb (vpn-232-165.phx2.redhat.com [10.3.232.165]) by int-mx08.intmail.prod.int.phx2.redhat.com (8.13.8/8.13.8) with ESMTP id o7BGJ0Ar005862; Wed, 11 Aug 2010 12:19:00 -0400 Received: by fche.csb (Postfix, from userid 2569) id 8F48F5814A; Wed, 11 Aug 2010 12:18:59 -0400 (EDT) To: Prerna Saxena Cc: systemtap@sourceware.org, Ananth , Stefan Hajnoczi , Mahesh Jagannath Salgaonkar , Srikar Dronamraju Subject: Re: Qemu tracing References: <4C611567.9030407@linux.vnet.ibm.com> From: fche@redhat.com (Frank Ch. Eigler) Date: Wed, 11 Aug 2010 16:19:00 -0000 In-Reply-To: <4C611567.9030407@linux.vnet.ibm.com> (Prerna Saxena's message of "Tue, 10 Aug 2010 14:31:27 +0530") Message-ID: User-Agent: Gnus/5.1008 (Gnus v5.10.8) Emacs/21.4 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Mailing-List: contact systemtap-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Post: List-Help: , Sender: systemtap-owner@sourceware.org X-SW-Source: 2010-q3/txt/msg00228.txt.bz2 prerna wrote: > Here's an update on a self contained userspace tracer mechanism I've > been working on, for QEMU ; alongwith Stefan Hajnoczi. Thank you! > [...] > To make guest tracing with QEMU truly independent of the host on which > it runs, QEMU must be instrumented by self-contained tracer. OK. How did you choose the events (probe points) for tracing? > When running QEMU on a linux host, one has the choice of using LTTnG > as the supported backend for tracing. [...] Using would be a natural second alternative for linux (and dtrace platforms, if someone cares). Even without that, have you tried applying normal systemtap user-space probing to qemu to get some usability / performance impressions? - FChE