From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 5641 invoked by alias); 3 Dec 2003 22:30:20 -0000 Mailing-List: contact gdb-help@sources.redhat.com; run by ezmlm Precedence: bulk List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-owner@sources.redhat.com Received: (qmail 5629 invoked from network); 3 Dec 2003 22:30:19 -0000 Received: from unknown (HELO blount.mail.mindspring.net) (207.69.200.226) by sources.redhat.com with SMTP; 3 Dec 2003 22:30:19 -0000 Received: from user-119a90a.biz.mindspring.com ([66.149.36.10] helo=berman.michael-chastain.com) by blount.mail.mindspring.net with esmtp (Exim 3.33 #1) id 1ARfV7-0003Cy-00; Wed, 03 Dec 2003 17:29:41 -0500 Received: by berman.michael-chastain.com (Postfix, from userid 502) id 96C974B35A; Wed, 3 Dec 2003 17:29:46 -0500 (EST) To: cagney@gnu.org, mec.gnu@mindspring.com Subject: Re: Slow handling of C++ symbol names Cc: drow@mvista.com, gdb@sources.redhat.com, ian@wasabisystems.com Message-Id: <20031203222946.96C974B35A@berman.michael-chastain.com> Date: Wed, 03 Dec 2003 22:30:00 -0000 From: mec.gnu@mindspring.com (Michael Elizabeth Chastain) X-SW-Source: 2003-12/txt/msg00071.txt.bz2 Here is a new table: gdb memory utime stime elapsed 5.3 263M 85.47 26.80 189.68 6.0 264M 83.76 26.08 187.90 H19 263M 83.44 25.99 190.00 H21 46M 7.37 2.07 9.46 H30 46M 2.72 0.29 3.03 H19 is gdb HEAD 2003-11-19 16:00:00 UTC. This has the exact same demangler as gdb 6.0 (modulo comments). H21 is gdb HEAD 2003-11-21 17:00:00 UTC. This has the old demangler with two bug-fix patches. H01 is gdb HEAD 2003-11-30 06:08:24 UTC. This is the new demangler. Nothing happened to performance from 5.3 to 6.0 or from 6.0 to H19. Something happened between H19 and H21. So I did: cvs diff -u -D "2003-11-19 16:00:00 UTC" -D "2003-11-21 17:00:00 UTC" This gives about 2000 lines of changes from H19 to H21, very manageable. Nothing changed in gdb c++ support. All the good changes were in libiberty/cp-demangle.c. So I believe the bug fixes in the old demangler were very effective. Either that, or they introduced new bugs which cause gdb to get to its first prompt a lot sooner. Something happened from H19 to H30. I don't know if it's gdb or the demangler, but I'm inclined to credit the demangler. Michael C