From owner-freebsd-current Tue Jul 2 18: 6:30 2002 Delivered-To: freebsd-current@freebsd.org Received: from mx1.FreeBSD.org (mx1.FreeBSD.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 9713A37B400 for ; Tue, 2 Jul 2002 18:06:27 -0700 (PDT) Received: from apollo.backplane.com (apollo.backplane.com [216.240.41.2]) by mx1.FreeBSD.org (Postfix) with ESMTP id 45AD343E42 for ; Tue, 2 Jul 2002 18:06:27 -0700 (PDT) (envelope-from dillon@apollo.backplane.com) Received: from apollo.backplane.com (localhost [127.0.0.1]) by apollo.backplane.com (8.12.4/8.12.3) with ESMTP id g6316RT4008906; Tue, 2 Jul 2002 18:06:27 -0700 (PDT) (envelope-from dillon@apollo.backplane.com) Received: (from dillon@localhost) by apollo.backplane.com (8.12.4/8.12.3/Submit) id g6316Rwp008905; Tue, 2 Jul 2002 18:06:27 -0700 (PDT) (envelope-from dillon) Date: Tue, 2 Jul 2002 18:06:27 -0700 (PDT) From: Matthew Dillon Message-Id: <200207030106.g6316Rwp008905@apollo.backplane.com> To: "David O'Brien" Cc: FreeBSD current users Subject: Re: -current results (was something funny with soft updates?) References: <200207020314.g623Eke5038019@apollo.backplane.com> <20020702164756.E70767@dragon.nuxi.com> Sender: owner-freebsd-current@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG :You really cannot say this -- GCC 3.1 does things 2.95 doesn't. 3.1 has :a totally rewritten code scheduler. People can't get Pentium-4 and :Athlon tbird specific optimizations for free. : :You almost seem to be making a claim on the quality of generated code, :vs. just the run-time of the compiler. The two are different. : I am making no such claim. I began this investigation when Julian forwarded some reports, and his own observations, that softupdates did not seem to have the huge improvement in performance for buildworlds in -current verses -stable. My analysis is about softupdates, the only observation I made in regards to GCC3 was that it was taking far longer to compile the same source. I made no statements on GCC3's code generation quality vs GCC2. - However, since you asked, I will say that I am not at all impressed with GCC3 vs GCC2. I've looked at a considerable amount of code with objdump between -stable and -current and GCC3 doesn't really seem to improve things much at all and in some run-time tests it seems to produce even worse code then GCC2 did.... and GCC2 produced pretty bad code. I see no improvement in cpu-intensive applications when I run a GCC2-generated binary and a GCC3-generated binary on the same machine, side by side. -Matt Matthew Dillon To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-current" in the body of the message