From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 2359 invoked by alias); 1 Aug 2005 09:53:15 -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 2346 invoked by uid 22791); 1 Aug 2005 09:53:12 -0000 Received: from public.id2-vpn.continvity.gns.novell.com (HELO gwia-smtp.id2.novell.com) (195.33.99.129) by sourceware.org (qpsmtpd/0.30-dev) with ESMTP; Mon, 01 Aug 2005 09:53:12 +0000 Received: from [192.168.0.3] (l4-client.id2.novell.com [149.44.117.251]) by gwia-smtp.id2.novell.com; Mon, 01 Aug 2005 10:52:50 +0100 Subject: re: Large, modular C++ application performance ... From: michael meeks Reply-To: michael.meeks@novell.com To: dank@kegel.com Cc: gcc@gcc.gnu.org In-Reply-To: <63935.64.85.15.162.1122736787.squirrel@webmail1.pair.com> References: <63935.64.85.15.162.1122736787.squirrel@webmail1.pair.com> Content-Type: text/plain Date: Mon, 01 Aug 2005 09:53:00 -0000 Message-Id: <1122889958.19623.119.camel@linux.site> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit X-SW-Source: 2005-08/txt/msg00013.txt.bz2 Hi Dan, On Sat, 2005-07-30 at 11:19 -0400, dank@kegel.com wrote: > MM wrote in http://go-oo.org/~michael/OOoStartup.pdf: > "... not one slot was overridden by an implementation > method external to the implementing library." This is really an issue rather orthogonal to that of 'final', what I'm trying to say (clearly, rather badly) - is that in those 3 libraries there were 0 instances of virtual functions of a given class implemented in that DSO, being implemented outside that DSO.[1] The significance of this is that - if we can markup classes to generate internal relocations for their overridden slots, and copy the parent library's (also internally) relocated version for inherited slots, (during this proposed idle vtable relocation process). Then we would avoid needing ~any named relocations at all to construct these vtables. ie. go from many tens of thousands of the slowest type of relocation, to none. HTH, Michael. [1] - further research AFAIR showed only a handful of these instances across all OO.o libraries. -- michael.meeks@novell.com <><, Pseudo Engineer, itinerant idiot