From owner-freebsd-stable@FreeBSD.ORG Sat Oct 20 17:39:45 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 9C5FE16A419; Sat, 20 Oct 2007 17:39:45 +0000 (UTC) (envelope-from rwatson@FreeBSD.org) Received: from cyrus.watson.org (cyrus.watson.org [209.31.154.42]) by mx1.freebsd.org (Postfix) with ESMTP id 40C5F13C459; Sat, 20 Oct 2007 17:39:40 +0000 (UTC) (envelope-from rwatson@FreeBSD.org) Received: from fledge.watson.org (fledge.watson.org [209.31.154.41]) by cyrus.watson.org (Postfix) with ESMTP id 6500246E2C; Sat, 20 Oct 2007 13:21:33 -0400 (EDT) Date: Sat, 20 Oct 2007 18:21:33 +0100 (BST) From: Robert Watson X-X-Sender: robert@fledge.watson.org To: Kris Kennaway In-Reply-To: <4719B06F.3000103@FreeBSD.org> Message-ID: <20071020181811.W70919@fledge.watson.org> References: <20071019232846.GQ31826@elvis.mu.org> <4719B06F.3000103@FreeBSD.org> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed Cc: stable@freebsd.org, Alfred Perlstein , 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: Sat, 20 Oct 2007 17:39:45 -0000 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. Robert N M Watson Computer Laboratory University of Cambridge