From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Eli Zaretskii Newsgroups: gmane.emacs.help Subject: Re: 64 bit official Windows builds Date: Thu, 11 Feb 2016 22:50:39 +0200 Message-ID: <83wpqb7yzk.fsf@gnu.org> References: <2577057e-98d3-41ce-ade2-1496648b09c3@googlegroups.com> <8337t3qdpd.fsf@gnu.org> NNTP-Posting-Host: plane.gmane.org X-Trace: ger.gmane.org 1455223880 5242 80.91.229.3 (11 Feb 2016 20:51:20 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Thu, 11 Feb 2016 20:51:20 +0000 (UTC) To: help-gnu-emacs@gnu.org Original-X-From: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane.org@gnu.org Thu Feb 11 21:51:15 2016 Return-path: Envelope-to: geh-help-gnu-emacs@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 1aTyCp-0005Er-DC for geh-help-gnu-emacs@m.gmane.org; Thu, 11 Feb 2016 21:51:15 +0100 Original-Received: from localhost ([::1]:53465 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aTyCo-0006aJ-KD for geh-help-gnu-emacs@m.gmane.org; Thu, 11 Feb 2016 15:51:14 -0500 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:40256) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aTyCR-0006YD-Q2 for help-gnu-emacs@gnu.org; Thu, 11 Feb 2016 15:50:52 -0500 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1aTyCN-0002y9-H9 for help-gnu-emacs@gnu.org; Thu, 11 Feb 2016 15:50:51 -0500 Original-Received: from fencepost.gnu.org ([2001:4830:134:3::e]:32904) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aTyCN-0002xy-C3 for help-gnu-emacs@gnu.org; Thu, 11 Feb 2016 15:50:47 -0500 Original-Received: from 84.94.185.246.cable.012.net.il ([84.94.185.246]:4952 helo=home-c4e4a596f7) by fencepost.gnu.org with esmtpsa (TLS1.2:RSA_AES_128_CBC_SHA1:128) (Exim 4.82) (envelope-from ) id 1aTyCM-00070K-KG for help-gnu-emacs@gnu.org; Thu, 11 Feb 2016 15:50:47 -0500 In-reply-to: (message from Stefan Monnier on Thu, 11 Feb 2016 08:58:45 -0500) 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: 2.1.14 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-bounces+geh-help-gnu-emacs=m.gmane.org@gnu.org Xref: news.gmane.org gmane.emacs.help:109117 Archived-At: > From: Stefan Monnier > Date: Thu, 11 Feb 2016 08:58:45 -0500 > > >> Could I ask, what is the benefit of 64 bits compared to 32 bits for windows ? > > It will run roughly twice faster. > [...] > > slower, because running a 32-bit executable on a 64-bit Windows > > requires expensive thunking for every call to any Windows API, > > Holy crap? Really? It's hard to believe that 64-bit Windows's > emulation of the 32-bit API is so inefficient that it causes a "rough > slowdown" by a factor 2 in an application like Emacs. > > Do you see such a factor-of-2 difference when doing "rm lisp/**/*.elc; > make"? Or in which kind of circumstance have you seen such a slowdown? I measured that by running GNU Find compiled from the same sources on a large and deep directory tree on the same Windows 7 box. That thunking is the culprit is my theory, not a fact; however, I cannot find any other explanation. If someone does, I'm all ears.