From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 2720 invoked by alias); 26 Nov 2013 12:39:24 -0000 Mailing-List: contact gdb-patches-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-patches-owner@sourceware.org Received: (qmail 2711 invoked by uid 89); 26 Nov 2013 12:39:23 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-3.7 required=5.0 tests=AWL,BAYES_00,RDNS_NONE,SPF_HELO_PASS,SPF_PASS,URIBL_BLOCKED autolearn=no version=3.3.2 X-HELO: mx1.redhat.com Received: from Unknown (HELO mx1.redhat.com) (209.132.183.28) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with ESMTP; Tue, 26 Nov 2013 12:38:11 +0000 Received: from int-mx12.intmail.prod.int.phx2.redhat.com (int-mx12.intmail.prod.int.phx2.redhat.com [10.5.11.25]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id rAQCc2gZ020038 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Tue, 26 Nov 2013 07:38:03 -0500 Received: from host2.jankratochvil.net (ovpn-116-32.ams2.redhat.com [10.36.116.32]) by int-mx12.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id rAQCbxxF003572 (version=TLSv1/SSLv3 cipher=AES128-SHA bits=128 verify=NO); Tue, 26 Nov 2013 07:38:02 -0500 Date: Tue, 26 Nov 2013 13:48:00 -0000 From: Jan Kratochvil To: "Metzger, Markus T" Cc: "gdb-patches@sourceware.org" Subject: Re: [patch v6 21/21] record-btrace: add (reverse-)stepping support Message-ID: <20131126123759.GA16244@host2.jankratochvil.net> References: <1379676639-31802-1-git-send-email-markus.t.metzger@intel.com> <1379676639-31802-22-git-send-email-markus.t.metzger@intel.com> <20131006195158.GF28020@host2.jankratochvil.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.21 (2010-09-15) X-IsSubscribed: yes X-SW-Source: 2013-11/txt/msg00808.txt.bz2 On Wed, 06 Nov 2013 14:48:29 +0100, Metzger, Markus T wrote: > > I would see it worth a comment even in > > (gdb) help record btrace > > Start branch trace recording. > > I don't think that this is necessary or helpful. If we start documenting the > trace size here, we should also say that trace is collected per thread with > no correlation between threads and that tracing induces a run-time overhead > and that it may also affect thread interleaving which may cause bug symptoms > to disappear, and .... Tom for example recently added a TODO item to fix it all in general: https://sourceware.org/gdb/wiki/ProjectIdeas?action=diff&rev1=57&rev2=58 More text is better than less text. But I do not insist on that. Thanks, Jan