From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 16950 invoked by alias); 18 Oct 2004 23:47:16 -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 16942 invoked from network); 18 Oct 2004 23:47:15 -0000 Received: from unknown (HELO nevyn.them.org) (66.93.172.17) by sourceware.org with SMTP; 18 Oct 2004 23:47:15 -0000 Received: from drow by nevyn.them.org with local (Exim 4.34 #1 (Debian)) id 1CJhDe-00074E-VN; Mon, 18 Oct 2004 19:47:15 -0400 Date: Tue, 19 Oct 2004 13:20:00 -0000 From: Daniel Jacobowitz To: David Anderson Cc: gdb@sources.redhat.com Subject: Re: RFC remove cache thrashing Message-ID: <20041018234714.GA26992@nevyn.them.org> Mail-Followup-To: David Anderson , gdb@sources.redhat.com References: <200410182339.i9INdir2188120@quasar.engr.sgi.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <200410182339.i9INdir2188120@quasar.engr.sgi.com> User-Agent: Mutt/1.5.5.1+cvs20040105i X-SW-Source: 2004-10/txt/msg00351.txt.bz2 On Mon, Oct 18, 2004 at 04:39:44PM -0700, David Anderson wrote: > gdb has N-squared behavior on getting registers when nptl > threads on Linux are in use. gdb thrashes the register-cache. I hadn't replied to your past posts because I didn't have time to reproduce the problem; last time I checked, it wasn't quadratic. I don't know what about your setup made the difference, or maybe my measurements are just out of date. Fixing this is very easy. I plan to remove the entire mess of affected code, once I finish renaming thread-db.c, which will hopefully be this week. We don't need to use thread-db for registers at all. > Has this multiple-register-cache idea been considered seriously before? > Is there any proposed outline-of-change? We need to get rid of all the remaining references to the "current" registers first. I don't think we're quite there yet. -- Daniel Jacobowitz