From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!.POSTED!not-for-mail From: Alex Newsgroups: gmane.emacs.bugs Subject: bug#24720: Performance impact of -no-pie Date: Mon, 17 Oct 2016 22:06:11 -0600 Message-ID: <87vawql2rw.fsf@gmail.com> References: <60845a3c-9167-faa1-2875-962e7025cc1f@cs.ucla.edu> <2e4bd054-3bed-501a-de51-55216eb2377f@cs.ucla.edu> NNTP-Posting-Host: blaine.gmane.org Mime-Version: 1.0 Content-Type: text/plain X-Trace: blaine.gmane.org 1476763655 8761 195.159.176.226 (18 Oct 2016 04:07:35 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Tue, 18 Oct 2016 04:07:35 +0000 (UTC) User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/25.1 (gnu/linux) Cc: 24720@debbugs.gnu.org To: Paul Eggert Original-X-From: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane.org@gnu.org Tue Oct 18 06:07:30 2016 Return-path: Envelope-to: geb-bug-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 1bwLgH-00083T-H0 for geb-bug-gnu-emacs@m.gmane.org; Tue, 18 Oct 2016 06:07:13 +0200 Original-Received: from localhost ([::1]:38850 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bwLgJ-0007B3-B3 for geb-bug-gnu-emacs@m.gmane.org; Tue, 18 Oct 2016 00:07:15 -0400 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:43307) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bwLgB-0007Ay-2m for bug-gnu-emacs@gnu.org; Tue, 18 Oct 2016 00:07:07 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1bwLg6-0006JD-V3 for bug-gnu-emacs@gnu.org; Tue, 18 Oct 2016 00:07:07 -0400 Original-Received: from debbugs.gnu.org ([208.118.235.43]:59468) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1bwLg6-0006Iv-Ra for bug-gnu-emacs@gnu.org; Tue, 18 Oct 2016 00:07:02 -0400 Original-Received: from Debian-debbugs by debbugs.gnu.org with local (Exim 4.84_2) (envelope-from ) id 1bwLg6-0000KW-GF for bug-gnu-emacs@gnu.org; Tue, 18 Oct 2016 00:07:02 -0400 X-Loop: help-debbugs@gnu.org Resent-From: Alex Original-Sender: "Debbugs-submit" Resent-CC: bug-gnu-emacs@gnu.org Resent-Date: Tue, 18 Oct 2016 04:07:02 +0000 Resent-Message-ID: Resent-Sender: help-debbugs@gnu.org X-GNU-PR-Message: followup 24720 X-GNU-PR-Package: emacs X-GNU-PR-Keywords: Original-Received: via spool by 24720-submit@debbugs.gnu.org id=B24720.14767635881223 (code B ref 24720); Tue, 18 Oct 2016 04:07:02 +0000 Original-Received: (at 24720) by debbugs.gnu.org; 18 Oct 2016 04:06:28 +0000 Original-Received: from localhost ([127.0.0.1]:37425 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1bwLfY-0000Jf-GC for submit@debbugs.gnu.org; Tue, 18 Oct 2016 00:06:28 -0400 Original-Received: from mail-it0-f46.google.com ([209.85.214.46]:37234) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1bwLfW-0000JR-Nf for 24720@debbugs.gnu.org; Tue, 18 Oct 2016 00:06:27 -0400 Original-Received: by mail-it0-f46.google.com with SMTP id m138so69419581itm.0 for <24720@debbugs.gnu.org>; Mon, 17 Oct 2016 21:06:26 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=from:to:cc:subject:references:date:in-reply-to:message-id :user-agent:mime-version; bh=HExZgTVV13rZAcuJrnDvWz3RsRicFfsLHkau3j48ATk=; b=LT7LrL2pb0+qAayYAkqU8Fb0BngEeoccfExR627prRa0aZfP+XPOSJ71D1AhxqZXUZ a5Z1MLWyQ3YCWNVqnYUQ7uTbEHgrwB8EVTGzDJoSGX7Chjr8BNDw7QK0Cmwy5l/Kqu/a 7bD1jJ8wRZcyQ9zG786c5J7ezSqGui5A40vNuOHpAGkmAYvKlIlPN1HM6ATR61ry0xTf o1W/7CZr+FGYbEo1myRcKPqxPJOhSCrzgP3bumTdK7RHn1qwsCqHe8iTmSrZzElTPs74 A2Lvpy4CSSSyX3zc/SnktyuXaRcm9OfgHK18S4yKd27anxdK29mx8l0jll7jLHQonZom hqJQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:from:to:cc:subject:references:date:in-reply-to :message-id:user-agent:mime-version; bh=HExZgTVV13rZAcuJrnDvWz3RsRicFfsLHkau3j48ATk=; b=Cgpc3rdeVnhCJqNXICltMQPZ5vU1pXnDKuGMhni82ta8kOgX7gDcXZVfx0aqcEMuKg UfT/8GE7594qDo69ryyu8IkAKaMp75gB7wb4z7X+O3QrTUEhyAprEkRNQRJiyHMZJ7tX 3VoRGSUgKOiA6bZZK7OTKvUIBzx61dUBpDvnoJEa5KibXjDPTnMytEqznAKahlPFw6aF x90MhgE6VGtxtbIILK1FPZht73dtWd39vorF32zNxgYO4rFOBImNOVYJpopxOBIoZ9Ly 8tDHEo4HN0pvWg0dPSMT22IWyzLzkroHKKKRdsDRiEe1Tahd0JN0lg11ahZ7rHQy4adI 3uJg== X-Gm-Message-State: AA6/9RlcGpH3ygF1J9arxvd25Hc1bt5kfcgGuu+f7c5YDj6+c7WsR2v7kKfXUMglAHTlsQ== X-Received: by 10.36.64.2 with SMTP id n2mr11478757ita.34.1476763580994; Mon, 17 Oct 2016 21:06:20 -0700 (PDT) Original-Received: from lylat (S01061859339e9903.ss.shawcable.net. [174.2.107.88]) by smtp.gmail.com with ESMTPSA id m31sm14802003ioi.40.2016.10.17.21.06.20 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Mon, 17 Oct 2016 21:06:20 -0700 (PDT) In-Reply-To: <2e4bd054-3bed-501a-de51-55216eb2377f@cs.ucla.edu> (Paul Eggert's message of "Mon, 17 Oct 2016 13:26:32 -0700") X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.18 Precedence: list X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 208.118.235.43 X-BeenThere: bug-gnu-emacs@gnu.org List-Id: "Bug reports for GNU Emacs, the Swiss army knife of text editors" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane.org@gnu.org Original-Sender: "bug-gnu-emacs" Xref: news.gmane.org gmane.emacs.bugs:124616 Archived-At: Paul Eggert writes: >> Is such a performance impact expected? If so, is there a plan to regain the > old speed? > > No, such a performance change is not expected. > > Can you reproduce the problem with the emacs-25 or master branches, without > manually adding -no-pie to CFLAGS? The bleeding-edge versions of Emacs attack > the problem in a slightly different way, which might affect performance less. > > If you still see a performance problem, can you narrow it down, e.g., by > configuring it with --enable-profiling and seeing where the extra cycles are > going? Ah, I see. It looks like the bleeding-edge versions add -no-pie to LDFLAGS instead of CFLAGS. Doing the same thing myself both to those versions and the 25.1 tarball (which is what I was using before) now results in the same performance as before, within error. Is it a bug that adding -no-pie to CFLAGS slows startup and runtime performance by a factor of 2? I would have expected that -no-pie would generally be faster compared to -pie. Is that not the case? Thanks.