From owner-freebsd-hackers@FreeBSD.ORG Thu Jul 8 07:46:35 2004 Return-Path: Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id C5D2616A4CE; Thu, 8 Jul 2004 07:46:35 +0000 (GMT) Received: from mail.eecs.harvard.edu (bowser.eecs.harvard.edu [140.247.60.24]) by mx1.FreeBSD.org (Postfix) with ESMTP id 7FA9743D2D; Thu, 8 Jul 2004 07:46:35 +0000 (GMT) (envelope-from ellard@eecs.harvard.edu) Received: from localhost (localhost.eecs.harvard.edu [127.0.0.1]) by mail.eecs.harvard.edu (Postfix) with ESMTP id E65F754C6A0; Thu, 8 Jul 2004 03:46:24 -0400 (EDT) Received: from mail.eecs.harvard.edu ([127.0.0.1]) by localhost (bowser.eecs.harvard.edu [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 79196-04; Thu, 8 Jul 2004 03:46:24 -0400 (EDT) Received: by mail.eecs.harvard.edu (Postfix, from userid 465) id BCC7254C692; Thu, 8 Jul 2004 03:46:24 -0400 (EDT) Received: from localhost (localhost [127.0.0.1]) by mail.eecs.harvard.edu (Postfix) with ESMTP id BA5F454C690; Thu, 8 Jul 2004 03:46:24 -0400 (EDT) Date: Thu, 8 Jul 2004 03:46:24 -0400 (EDT) From: Daniel Ellard To: David Schultz In-Reply-To: <20040708034845.GA59801@VARK.homeunix.com> Message-ID: <20040708033741.E28518@bowser.eecs.harvard.edu> References: <20040706120130.3DF9816A57D@hub.freebsd.org> <40EB9A46.2050409@trio.plala.or.jp> <20040708034845.GA59801@VARK.homeunix.com> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII X-Virus-Scanned: by amavisd-new at eecs.harvard.edu cc: freebsd-hackers@FreeBSD.ORG Subject: Re: Article on Sun's DTrace X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 08 Jul 2004 07:46:35 -0000 On Wed, 7 Jul 2004, David Schultz wrote: > The page referenced earlier in this thread pointed out that 6 > staff-years went into DTrace. That's accurate, and we're not > talking about part-time employees or people who don't know what > they're doing. The D compiler aside, this is not a small matter > of programming that can just be ported to a new OS or machine > architecture in a few months. I don't doubt that DTrace took a long time to do. However, in most projects the design phase consumes a lot of time, and it is often the case that unforeseen problems or changes in the feature set cost the developers a lot of time. So while it might have taken six years to write DTrace the first time, I suspect it would take a fraction of that time to re-implement. (It certainly might be longer than "a few months" and I'm not going to quibble. We won't know the precise number until someone does the port.) -Dan