From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.blaine.gmane.org!not-for-mail From: Stefan Monnier via "Bug reports for GNU Emacs, the Swiss army knife of text editors" Newsgroups: gmane.emacs.bugs Subject: bug#56682: Fix the long lines font locking related slowdowns Date: Sun, 31 Jul 2022 19:00:11 -0400 Message-ID: References: <837d46mjen.fsf@gnu.org> <8a3eaeef01be5bfaa5ef@heytings.org> <05388e8d8812bfa3695d@heytings.org> <83v8rf5894.fsf@gnu.org> <65cb7c73fd4a999cca00@heytings.org> <8c7321f2f3400a5db9be@heytings.org> <8c7321f2f388e5343475@heytings.org> <6ea376f6-d503-06d8-6d83-50c52b695394@yandex.ru> <8c7321f2f3ac52bfee4b@heytings.org> <2f7eeea3-6ba9-d2c2-1fb9-dd40d2de2002@yandex.ru> Reply-To: Stefan Monnier Mime-Version: 1.0 Content-Type: text/plain Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="28226"; mail-complaints-to="usenet@ciao.gmane.io" User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/29.0.50 (gnu/linux) Cc: 56682@debbugs.gnu.org, Gregory Heytings , Eli Zaretskii To: Dmitry Gutov Original-X-From: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane-mx.org@gnu.org Mon Aug 01 01:01:28 2022 Return-path: Envelope-to: geb-bug-gnu-emacs@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 1oIHw8-0007FX-Gz for geb-bug-gnu-emacs@m.gmane-mx.org; 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Sun, 31 Jul 2022 23:01:02 +0000 Original-Received: (at 56682) by debbugs.gnu.org; 31 Jul 2022 23:00:23 +0000 Original-Received: from localhost ([127.0.0.1]:38804 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1oIHv4-0008JD-Va for submit@debbugs.gnu.org; Sun, 31 Jul 2022 19:00:23 -0400 Original-Received: from mailscanner.iro.umontreal.ca ([132.204.25.50]:42341) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1oIHv3-0008J0-7m for 56682@debbugs.gnu.org; Sun, 31 Jul 2022 19:00:21 -0400 Original-Received: from pmg3.iro.umontreal.ca (localhost [127.0.0.1]) by pmg3.iro.umontreal.ca (Proxmox) with ESMTP id BFFAA4411C0; Sun, 31 Jul 2022 19:00:15 -0400 (EDT) Original-Received: from mail01.iro.umontreal.ca (unknown [172.31.2.1]) by pmg3.iro.umontreal.ca (Proxmox) with ESMTP id 7EAFD441144; Sun, 31 Jul 2022 19:00:14 -0400 (EDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=iro.umontreal.ca; s=mail; t=1659308414; bh=rQXwSmkhFZRWa4mINn+PQXsLnrSNSLCfIBUA5JwRU0A=; h=From:To:Cc:Subject:In-Reply-To:References:Date:From; b=YKZOk15N/sd+oFHLEmM3jP7sOfW20sTGsmou5B05QKioOc/54RYhLN+MDWgefGsRf qy5Ind0GqbJgja8ACCXgs/7888jlbtuJo3PQwglT5KEPH9N5XSu+eVtuoKJx/23D9w kGi7wMdRjisoUx11oKbfUYHoE1rFt+Gr3VLYB5r100nXKs/0ytawmSSdNXvaLkJqfD R06lS9ameDaWpyMu2Fd421A892Vj+REQjKIVsXuzhacMsa4gUiaOZwMHgQEirIadVF 9H4UcNpxu8v2jbjZyRoLmsNZV/hX5spTmKdVrNp9RVHxrCAiwqmXcPeOmgdkrvbTnr kYu9t7jl7t9Uw== Original-Received: from milanesa (dyn.144-85-174-155.dsl.vtx.ch [144.85.174.155]) by mail01.iro.umontreal.ca (Postfix) with ESMTPSA id 7D1971203B8; Sun, 31 Jul 2022 19:00:13 -0400 (EDT) In-Reply-To: <2f7eeea3-6ba9-d2c2-1fb9-dd40d2de2002@yandex.ru> (Dmitry Gutov's message of "Mon, 1 Aug 2022 01:42:24 +0300") X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.18 Precedence: list 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-mx.org@gnu.org Original-Sender: "bug-gnu-emacs" Xref: news.gmane.io gmane.emacs.bugs:238377 Archived-At: > But one big slow scan (and how slow it is actually depends on a particular > major mode) Indeed, I think the `syntax-ppss` part itself should be fast enough even if very large files. But the `syntax-propertize` part (which is called by `syntax-ppss`) can take a long time in some major modes. In those major modes where that's a problem (i.e. major modes that have a complex `syntax-propertize-function` and that also happen to be used in very large files) maybe it would be worth (re)introducing some sort of `syntax(-propertize)-begin-function`. But these kinds of heuristics have proved problematic over the years (and they'd introduce extra complexity since we won't be able to just rely on a `syntax-propertize-done` high-watermark to know what's been propertized and what hasn't, combined with the interaction with the `syntax-ppss` cache), so we'd have to try a few different approaches. In any case this is not a long-lines problem. Stefan