From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!.POSTED!not-for-mail From: Eli Zaretskii Newsgroups: gmane.emacs.help Subject: Re: Question about memory usage Date: Tue, 03 Apr 2018 17:03:16 +0300 Message-ID: <834lks5qvv.fsf@gnu.org> References: <83sh8c6byb.fsf@gnu.org> <838ta45upw.fsf@gnu.org> NNTP-Posting-Host: blaine.gmane.org X-Trace: blaine.gmane.org 1522764139 22829 195.159.176.226 (3 Apr 2018 14:02:19 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Tue, 3 Apr 2018 14:02:19 +0000 (UTC) To: help-gnu-emacs@gnu.org Original-X-From: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane.org@gnu.org Tue Apr 03 16:02:15 2018 Return-path: Envelope-to: geh-help-gnu-emacs@m.gmane.org Original-Received: from lists.gnu.org ([208.118.235.17]) by blaine.gmane.org with esmtp (Exim 4.84_2) (envelope-from ) id 1f3MVq-0005p9-Ty for geh-help-gnu-emacs@m.gmane.org; Tue, 03 Apr 2018 16:02:15 +0200 Original-Received: from localhost ([::1]:37007 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1f3MXt-0003uP-0v for geh-help-gnu-emacs@m.gmane.org; Tue, 03 Apr 2018 10:04:21 -0400 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:35494) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1f3MWl-0003os-9Z for help-gnu-emacs@gnu.org; Tue, 03 Apr 2018 10:03:19 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1f3MWi-0005WX-7r for help-gnu-emacs@gnu.org; Tue, 03 Apr 2018 10:03:11 -0400 Original-Received: from fencepost.gnu.org ([2001:4830:134:3::e]:42771) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1f3MWi-0005WT-4K for help-gnu-emacs@gnu.org; Tue, 03 Apr 2018 10:03:08 -0400 Original-Received: from [176.228.60.248] (port=2756 helo=home-c4e4a596f7) by fencepost.gnu.org with esmtpsa (TLS1.2:RSA_AES_256_CBC_SHA1:256) (Exim 4.82) (envelope-from ) id 1f3MWh-0004t3-Q3 for help-gnu-emacs@gnu.org; Tue, 03 Apr 2018 10:03:08 -0400 In-reply-to: (message from Stefan Monnier on Tue, 03 Apr 2018 09:13:44 -0400) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 2001:4830:134:3::e X-BeenThere: help-gnu-emacs@gnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: Users list for the GNU Emacs text editor List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane.org@gnu.org Original-Sender: "help-gnu-emacs" Xref: news.gmane.org gmane.emacs.help:116322 Archived-At: > From: Stefan Monnier > Date: Tue, 03 Apr 2018 09:13:44 -0400 > > >> Hmm... why would setting this var make any significant difference here? > > Because the variable is on/referenced via the stack, I suppose. > > I don't follow. At the end of each iteration of the loop, we kill the > temp buffer, so the effect of having set its buffer-undo-list slot or > not should be negligible (or more specifically: this effect should only > exist until the next GC). As I said: maybe I misunderstand what you are asking. So let me say something that perhaps better matches your question: a temporary buffer has its undo turned off, but setting buffer-undo-list to nil turns this on again, so inserting a character into the buffer conses stuff onto the undo-list. Does that answer the question "why would setting the variable make any difference"?