From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Ken Raeburn Newsgroups: gmane.emacs.devel Subject: Re: t and nil in pure memory? Date: Wed, 18 Nov 2009 13:53:28 -0500 Message-ID: References: <200911112023.nABKNrH6023933@godzilla.ics.uci.edu> <87pr7oxieq.fsf@freebits.de> <200911130524.nAD5O5uu009102@godzilla.ics.uci.edu> <200911152108.nAFL8IBl006966@godzilla.ics.uci.edu> NNTP-Posting-Host: lo.gmane.org Mime-Version: 1.0 (Apple Message framework v936) Content-Type: text/plain; charset=US-ASCII; format=flowed; delsp=yes Content-Transfer-Encoding: 7bit X-Trace: ger.gmane.org 1258570436 31711 80.91.229.12 (18 Nov 2009 18:53:56 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Wed, 18 Nov 2009 18:53:56 +0000 (UTC) To: Emacs development discussions Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Wed Nov 18 19:53:49 2009 Return-path: Envelope-to: ged-emacs-devel@m.gmane.org Original-Received: from lists.gnu.org ([199.232.76.165]) by lo.gmane.org with esmtp (Exim 4.50) id 1NApf3-0007Wo-NE for ged-emacs-devel@m.gmane.org; Wed, 18 Nov 2009 19:53:49 +0100 Original-Received: from localhost ([127.0.0.1]:35805 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1NApf3-00052x-9H for ged-emacs-devel@m.gmane.org; Wed, 18 Nov 2009 13:53:49 -0500 Original-Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1NApex-00052d-VB for emacs-devel@gnu.org; Wed, 18 Nov 2009 13:53:43 -0500 Original-Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1NApet-00051j-4Z for emacs-devel@gnu.org; Wed, 18 Nov 2009 13:53:43 -0500 Original-Received: from [199.232.76.173] (port=38642 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1NApes-00051g-VW for emacs-devel@gnu.org; Wed, 18 Nov 2009 13:53:39 -0500 Original-Received: from splat.raeburn.org ([69.25.196.39]:58264 helo=raeburn.org) by monty-python.gnu.org with esmtps (TLS-1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.60) (envelope-from ) id 1NApek-0004Wq-Aw for emacs-devel@gnu.org; Wed, 18 Nov 2009 13:53:38 -0500 Original-Received: from [10.0.0.158] ([10.0.0.158]) by raeburn.org (8.14.3/8.14.1) with ESMTP id nAIIrSlJ004681; Wed, 18 Nov 2009 13:53:28 -0500 (EST) In-Reply-To: X-Mailer: Apple Mail (2.936) X-detected-operating-system: by monty-python.gnu.org: Genre and OS details not recognized. X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: "Emacs development discussions." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Original-Sender: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Errors-To: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Xref: news.gmane.org gmane.emacs.devel:117199 Archived-At: On Nov 15, 2009, at 20:34, Stefan Monnier wrote: >> The big problem in GC is the trashing of the memory system due to >> setting/resetting and reading the mark bits... > > Could be as well. In that case, maybe we should move all the markbits > to separate bitvectors like we have for cons and floats. There are lots of changes, major or minor, that might be worth exploring. Prefetching, putting mark bits on different words or pages, tri-color schemes, incremental marking, generational GC, etc., etc. But maybe we should also consider a more drastic change: Use Hans Boehm's GC library. (Guile has recently switched to using it. So if my Guile-Emacs work ever catches on, use of bdw-gc would happen as a side effect.) If it doesn't simply make the performance someone else's problem to focus on, it at least lets us share the workload with a wider community. Ken