From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Eli Zaretskii Newsgroups: gmane.emacs.devel Subject: Re: GC and stack marking Date: Mon, 19 May 2014 23:03:22 +0300 Message-ID: <83ppj9bkol.fsf@gnu.org> References: <83a9add91p.fsf@gnu.org> <537A51C0.50008@cs.ucla.edu> <83vbt1bmxt.fsf@gnu.org> <537A626A.5060506@cs.ucla.edu> Reply-To: Eli Zaretskii NNTP-Posting-Host: plane.gmane.org X-Trace: ger.gmane.org 1400533298 28279 80.91.229.3 (19 May 2014 21:01:38 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Mon, 19 May 2014 21:01:38 +0000 (UTC) Cc: fabrice.popineau@gmail.com, emacs-devel@gnu.org To: Paul Eggert Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Mon May 19 23:01:30 2014 Return-path: Envelope-to: ged-emacs-devel@m.gmane.org Original-Received: from lists.gnu.org ([208.118.235.17]) by plane.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1WmUgb-0002s5-TL for ged-emacs-devel@m.gmane.org; Mon, 19 May 2014 23:01:30 +0200 Original-Received: from localhost ([::1]:50019 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1WmTmW-0006wY-T4 for ged-emacs-devel@m.gmane.org; Mon, 19 May 2014 16:03:32 -0400 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:45483) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1WmTmO-0006w1-Ro for emacs-devel@gnu.org; Mon, 19 May 2014 16:03:30 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1WmTmJ-0001iZ-9u for emacs-devel@gnu.org; Mon, 19 May 2014 16:03:24 -0400 Original-Received: from mtaout27.012.net.il ([80.179.55.183]:46891) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1WmTmJ-0001gu-2Y for emacs-devel@gnu.org; Mon, 19 May 2014 16:03:19 -0400 Original-Received: from conversion-daemon.mtaout27.012.net.il by mtaout27.012.net.il (HyperSendmail v2007.08) id <0N5U007006X5PW00@mtaout27.012.net.il> for emacs-devel@gnu.org; Mon, 19 May 2014 23:00:00 +0300 (IDT) Original-Received: from HOME-C4E4A596F7 ([87.69.4.28]) by mtaout27.012.net.il (HyperSendmail v2007.08) with ESMTPA id <0N5U0011K7K0GZ90@mtaout27.012.net.il>; Mon, 19 May 2014 23:00:00 +0300 (IDT) In-reply-to: <537A626A.5060506@cs.ucla.edu> X-012-Sender: halo1@inter.net.il X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.6.x X-Received-From: 80.179.55.183 X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: "Emacs development discussions." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Original-Sender: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Xref: news.gmane.org gmane.emacs.devel:171940 Archived-At: > Date: Mon, 19 May 2014 12:58:34 -0700 > From: Paul Eggert > CC: emacs-devel@gnu.org, fabrice.popineau@gmail.com > > On 05/19/2014 12:14 PM, Eli Zaretskii wrote: > >> > > >> >We could have the garbage collector treat purify-flag specially, I suppose. > > I'm not sure I understand the suggestion. Can you elaborate? > > I was thinking of a horrible hack where the GC knows about purify-flag, > so that when you set purify-flag to nil the GCC immediately frees the > object that purify-flag used to contain, and that we make purify-flag > special in this way. Right, but that would only work for that single object. The problem, by contrast, sounds more general than that. > Maybe we should get rid of the hash-table purify-flag hack, for > example. Maybe, I'm not sure I fully understand its purpose to begin with (speed of finding objects?). There's a comment by Stefan there saying something about some savings.