From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.blaine.gmane.org!not-for-mail From: Eli Zaretskii Newsgroups: gmane.emacs.devel Subject: Re: Indentation and gc Date: Mon, 13 Mar 2023 14:51:57 +0200 Message-ID: <83h6uou842.fsf@gnu.org> References: <20230310110747.4hytasakomvdyf7i.ref@Ergus> <20230310110747.4hytasakomvdyf7i@Ergus> <87a60k657y.fsf@web.de> <838rg4zmg9.fsf@gnu.org> <87ttyrwobj.fsf@localhost> <20230311111730.fatow74xnbel7t3f@Ergus> <83o7ozwju8.fsf@gnu.org> <87jzznwjh3.fsf@localhost> <83jzznwjeh.fsf@gnu.org> <87fsabwirg.fsf@localhost> <83h6urwhu0.fsf@gnu.org> <875yb7wgpd.fsf@localhost> <83bkkzwgcp.fsf@gnu.org> <87y1o3v1fr.fsf@localhost> <838rg3wf7k.fsf@gnu.org> <87v8j7v0a4.fsf@localhost> <835yb7were.fsf@gnu.org> <87r0tvuzpl.fsf@localhost> <834jqrwbgu.fsf@gnu.org> <87a60grf9t.fsf@localhost> Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="1801"; mail-complaints-to="usenet@ciao.gmane.io" Cc: spacibba@aol.com, arne_bab@web.de, emacs-devel@gnu.org To: Ihor Radchenko Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Mon Mar 13 13:52:50 2023 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 1pbhfW-0000Fp-GE for ged-emacs-devel@m.gmane-mx.org; Mon, 13 Mar 2023 13:52:50 +0100 Original-Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1pbhes-0007Gr-O1; Mon, 13 Mar 2023 08:52:10 -0400 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1pbher-0007Ge-BV for emacs-devel@gnu.org; Mon, 13 Mar 2023 08:52:09 -0400 Original-Received: from fencepost.gnu.org ([2001:470:142:3::e]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1pbheq-0000OL-JF; Mon, 13 Mar 2023 08:52:08 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=gnu.org; s=fencepost-gnu-org; h=References:Subject:In-Reply-To:To:From:Date: mime-version; bh=PP+I/Cy5vbOdzZ4wUFH+u3YRmwshrdIowUc8hKctzxw=; b=AScSFGzbJMZ8 WXYoqwO8QB+tloiVuuLstpO+xQ4HA4JCHOh6820EqHUmlHnjtBzGY5n/NG3hkwjWu0PlFWwi7+KlY 21nNekeQpWQixjIGF/6ChhM8K15kSSbF8q9jGbKABZXQKpn916G1y0b7wyY6q4ASq3BdY3+wFUUyO fN0/1fUf1Zwfh98QmcMnjmLG4YV2Req4ca885VwP7eupyK59gT5IBiRwil8tK4bUORhZWSeJNrxA+ /68UfAh79nxlP8d6E7kiEL8ruy9DxnU3MTEzqMIPMv4z2ZxEGZmjOCX5OH0MXXJakkYfp1k+kpjiK Y3IDUSCITxfPKvIA7llzaA==; Original-Received: from [87.69.77.57] (helo=home-c4e4a596f7) by fencepost.gnu.org with esmtpsa (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1pbhep-0004J1-U1; Mon, 13 Mar 2023 08:52:08 -0400 In-Reply-To: <87a60grf9t.fsf@localhost> (message from Ihor Radchenko on Mon, 13 Mar 2023 12:45:34 +0000) 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-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Xref: news.gmane.io gmane.emacs.devel:304391 Archived-At: > From: Ihor Radchenko > Cc: spacibba@aol.com, arne_bab@web.de, emacs-devel@gnu.org > Date: Mon, 13 Mar 2023 12:45:34 +0000 > > > If you specify a larger value, garbage collection will > > happen less often. This reduces the amount of time spent garbage > > collecting, but increases total memory use. You may want to do > > this when running a program that creates lots of Lisp data. > > However, we recommend against increasing the threshold for > > prolonged periods of time, and advise that you never set it higher > > than needed for the program to run in reasonable time. Using > > thresholds higher than necessary could potentially cause > > system-wide memory pressure, and should therefore be avoided. > > Unfortunately, if is not very clear how much increasing the threshold > affects memory usage. What if I increase the threshold twice? Is it > safe? Dangerous? Maybe 10%? 10x? How should I know? Does anyone know? > I guess we can give an answer if we collect usage statistics. Exactly. > > Again, you are reasoning about the value as if it were related to the > > maximum memory footprint Emacs could have. But in fact, it is related > > only to the _increment_ of memory Emacs can have before it should stop > > and consider how much of that is garbage. > > But how else should I interpret "memory pressure"? Increasing the threshold indeed increases the danger of memory pressure, but how exactly is yet unknown. So simplistic interpretations like this are IMO premature. > But then there is a warning about memory > pressure, but it does not look too scary if you have plenty of RAM, > especially looking at common advises to increase the threshold across > internet. Using most-positive-fixnum as the threshold _should_ scare people.