From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 28175 invoked by alias); 19 Oct 2002 17:40:28 -0000 Mailing-List: contact gcc-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Archive: List-Post: List-Help: Sender: gcc-owner@gcc.gnu.org Received: (qmail 28161 invoked from network); 19 Oct 2002 17:40:27 -0000 Received: from unknown (HELO www.eyesopen.com) (12.96.199.11) by sources.redhat.com with SMTP; 19 Oct 2002 17:40:27 -0000 Received: from localhost (roger@localhost) by www.eyesopen.com (8.9.3/8.9.3) with ESMTP id LAA08704; Sat, 19 Oct 2002 11:25:56 -0600 Date: Sat, 19 Oct 2002 14:51:00 -0000 From: Roger Sayle To: Zack Weinberg cc: , , Diego Novillo Subject: Re: Bootstrap times on mainline are getting worse Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII X-SW-Source: 2002-10/txt/msg01199.txt.bz2 Hi Zack, > > A 'time make bootstrap' on version "2002-10-03" gives: > > > > real 57m38.632s > > user 51m20.200s > > sys 4m55.500s > > > > With this patch I get: > > > > real 58m16.766s > > user 51m14.720s > > sys 5m0.850s > > I smell cache blowout. Notice how the real and system times went up, > but the user time went down? I think that you're barking up the wrong tree on this one. As I've mentioned in http://gcc.gnu.org/ml/gcc/2002-10/msg01183.html, we're still looking for a 6% (approx 4 minute slow-down) around October 5th. Total process times above, 56m:15.7 before and 56m:15.5 after showed that this patch itself had virtually no effect. The minor difference in wall clock times can easily be explained by attributed to other processes running on the same machine. Also be carefull about changing these RTX costs to unsigned char. Pentium4 already has integer division costs at around 120, and improvements in superscalar issue vs memory latency could easily push values above 256 on x86 within only a year or so. Just look at the curves for i386, i486, pentium, pentiumpro, pentium4.... Roger --