From owner-freebsd-stable@FreeBSD.ORG Sun Oct 21 08:56:31 2007 Return-Path: Delivered-To: stable@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id E949D16A419; Sun, 21 Oct 2007 08:56:31 +0000 (UTC) (envelope-from kris@FreeBSD.org) Received: from weak.local (hub.freebsd.org [IPv6:2001:4f8:fff6::36]) by mx1.freebsd.org (Postfix) with ESMTP id 0734613C455; Sun, 21 Oct 2007 08:56:29 +0000 (UTC) (envelope-from kris@FreeBSD.org) Message-ID: <471B143E.7050200@FreeBSD.org> Date: Sun, 21 Oct 2007 11:56:30 +0300 From: Kris Kennaway User-Agent: Thunderbird 2.0.0.6 (Macintosh/20070728) MIME-Version: 1.0 To: Alfred Perlstein References: <20071019232846.GQ31826@elvis.mu.org> <4719B06F.3000103@FreeBSD.org> <20071020181811.W70919@fledge.watson.org> <20071020192717.GX31826@elvis.mu.org> In-Reply-To: <20071020192717.GX31826@elvis.mu.org> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: stable@freebsd.org, Robert Watson , jhb@freebsd.org Subject: Re: LOCK_PROFILING in -stable X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 21 Oct 2007 08:56:32 -0000 Alfred Perlstein wrote: > * Robert Watson [071020 10:21] wrote: >> On Sat, 20 Oct 2007, Kris Kennaway wrote: >> >>> Alfred Perlstein wrote: >>>> Hey guys, I have LOCK_PROFILING done for a product based on FreeBSD-6, >>>> this means I can relatively easily backport LOCK_PROFILING from FreeBSD-7 >>>> to FreeBSD-6. >>>> >>>> Do we want this? >>>> >>>> I'd like to do it if people want it. >>> I think it should be done, performance is a lot better than the old 6.x >>> version and it also adds another very useful performance metric (time >>> spent waiting for the lock). The only concern is that it doesn't break >>> ABI support when not compiled in, but I'm pretty sure you've already told >>> me this is OK. Thanks for looking at this. >> This is my feeling also -- I would consider ABI breakage a show stopper for >> 6.x, but feel otherwise that the new code is much more mature and capable >> and would be quite beneficial to people building appliances and related >> products on 6.x. You might check with Attilio about whether there are any >> remaining outstanding issues that need to be resolved first, and make sure >> to send a heads up out on stable@ and put a note in UPDATING that the >> option and details have changed. > > I still get confused as to the meaning of this... > > It only breaks ABI when it's enabled. > > I think that is OK, right? > Yes, that is fine. Other existing debugging options also break ABI when enabled, so it's OK. Kris