From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.blaine.gmane.org!not-for-mail From: Alan Mackenzie Newsgroups: gmane.emacs.devel Subject: Re: Time to merge scratch/correct-warning-pos into master, perhaps? Date: Sun, 20 Feb 2022 20:56:02 +0000 Message-ID: References: <83v8xt20db.fsf@gnu.org> <83ee4gyzrh.fsf@gnu.org> <83v8xryh4d.fsf@gnu.org> <831qzyzt5t.fsf@gnu.org> <874k4u92gp.fsf@randomsample> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="38981"; mail-complaints-to="usenet@ciao.gmane.io" Cc: David Engster , mattiase@acm.org, emacs-devel@gnu.org, gregory@heytings.org, Eli Zaretskii , larsi@gnus.org To: Stefan Monnier Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Sun Feb 20 21:57:35 2022 Return-path: Envelope-to: ged-emacs-devel@m.gmane-mx.org Original-Received: from lists.gnu.org ([209.51.188.17]) by ciao.gmane.io with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1nLtGx-0009y3-Bs for ged-emacs-devel@m.gmane-mx.org; Sun, 20 Feb 2022 21:57:35 +0100 Original-Received: from localhost ([::1]:44970 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1nLtGv-00044B-Vq for ged-emacs-devel@m.gmane-mx.org; Sun, 20 Feb 2022 15:57:34 -0500 Original-Received: from eggs.gnu.org ([209.51.188.92]:49988) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1nLtFY-0002eu-QL for emacs-devel@gnu.org; Sun, 20 Feb 2022 15:56:08 -0500 Original-Received: from colin.muc.de ([193.149.48.1]:18991 helo=mail.muc.de) by eggs.gnu.org with smtp (Exim 4.90_1) (envelope-from ) id 1nLtFV-0003bV-BQ for emacs-devel@gnu.org; Sun, 20 Feb 2022 15:56:08 -0500 Original-Received: (qmail 46121 invoked by uid 3782); 20 Feb 2022 20:56:03 -0000 Original-Received: from acm.muc.de (p2e5d519e.dip0.t-ipconnect.de [46.93.81.158]) (using STARTTLS) by colin.muc.de (tmda-ofmipd) with ESMTP; Sun, 20 Feb 2022 21:56:02 +0100 Original-Received: (qmail 6151 invoked by uid 1000); 20 Feb 2022 20:56:02 -0000 Content-Disposition: inline In-Reply-To: X-Submission-Agent: TMDA/1.3.x (Ph3nix) X-Primary-Address: acm@muc.de Received-SPF: pass client-ip=193.149.48.1; envelope-from=acm@muc.de; helo=mail.muc.de X-Spam_score_int: -18 X-Spam_score: -1.9 X-Spam_bar: - X-Spam_report: (-1.9 / 5.0 requ) BAYES_00=-1.9, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.29 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-mx.org@gnu.org Original-Sender: "Emacs-devel" Xref: news.gmane.io gmane.emacs.devel:286538 Archived-At: Hello, Stefan. On Sun, Feb 20, 2022 at 15:37:55 -0500, Stefan Monnier wrote: > > I seem to have a default setting of 4kHz. This was enough to get several > > thousand hits in each build ("old" and "new") running the test suite. As > > I wrote in my post just now to Eli, the results came up contrary to what > > was expected - the "old" build, running the simple EQ spent more time in > > it than the "new" build running the complicated EQ. Possibly I've made > > some silly mistake in the measurements. > Maybe it's because EQ was used for NILP before but isn't used for it > any more? Bingo! That's surely the reason. In the new build, NILP wasn't using EQ. I'll sort that out and compare again. Just not tonight. Thank you very much! > In any case, in my experience measuring such things is wickedly > difficult. It's even hard to define what it is we really want to > measure because the impact will depend so heavily of how the code gets > inlined&scheduled by the compiler and then how it gets scheduled in the > CPU, and how branch prediction interacts with it, etc... I think I'm just trying to get some sort of handle on how much the code has slowed down because of EQ. Obviously, making EQ into a function (rather than an inline function) will have distorted things, but it seems the easiest way of measuring something at the moment. > Stefan -- Alan Mackenzie (Nuremberg, Germany).