From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 16016 invoked by alias); 13 Oct 2003 14:37:15 -0000 Mailing-List: contact gcc-bugs-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Archive: List-Post: List-Help: Sender: gcc-bugs-owner@gcc.gnu.org Received: (qmail 16006 invoked by uid 48); 13 Oct 2003 14:37:14 -0000 Date: Mon, 13 Oct 2003 14:37:00 -0000 Message-ID: <20031013143714.16005.qmail@sources.redhat.com> From: "steven at gcc dot gnu dot org" To: gcc-bugs@gcc.gnu.org In-Reply-To: <20030522192332.10944.pinskia@gcc.gnu.org> References: <20030522192332.10944.pinskia@gcc.gnu.org> Reply-To: gcc-bugzilla@gcc.gnu.org Subject: [Bug other/10944] alloc_page in ggc-page.c is slow X-Bugzilla-Reason: CC X-SW-Source: 2003-10/txt/msg00867.txt.bz2 List-Id: PLEASE REPLY TO gcc-bugzilla@gcc.gnu.org ONLY, *NOT* gcc-bugs@gcc.gnu.org. http://gcc.gnu.org/bugzilla/show_bug.cgi?id=10944 steven at gcc dot gnu dot org changed: What |Removed |Added ---------------------------------------------------------------------------- Last reconfirmed|2003-06-01 18:58:30 |2003-10-13 14:37:14 date| | ------- Additional Comments From steven at gcc dot gnu dot org 2003-10-13 14:37 ------- The new patch implements suggestion 1 from last nights list. Andrew, you identified the loop over free_pages as a time consumer, but now that it is gone, I get virtually no measurable time improvements (10ths of seconds on >1min total compilation time) for the test case for PR8361. Which (not surprisingly) once again shows that GC is slow because with each call ggc_collect we need to do more and more marking... Are you absolutely, positively sure that this loop is a performance hog? Perhaps you can try the patch, it bootstrappes (c,objc,c++) and showed no regressions on i686. So far I haven't found convincing evidence that it improves performance significantly except for the most pathological (artificial) cases. Sigh, back to waiting for a new GC strategy...