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.bugs Subject: bug#66020: (bug#64735 spin-off): regarding the default for read-process-output-max Date: Thu, 21 Sep 2023 17:59:36 +0300 Message-ID: <83msxf8td3.fsf@gnu.org> References: <83bkfs2tw5.fsf@gnu.org> <18a0b4d8-32bd-3ecd-8db4-32608a1ebba7@gutov.dev> <83il8lxjcu.fsf@gnu.org> <2e21ec81-8e4f-4c02-ea15-43bd6da3daa7@gutov.dev> <8334zmtwwi.fsf@gnu.org> <83tts0rkh5.fsf@gnu.org> <831qf3pd1y.fsf@gnu.org> <28a7916e-92d5-77ab-a61e-f85b59ac76b1@gutov.dev> <83sf7jnq0m.fsf@gnu.org> <5c493f86-0af5-256f-41a7-7d886ab4c5e4@gutov.dev> <83ledanvzw.fsf@gnu.org> <83r0n2m7qz.fsf@gnu.org> <26afa109-9ba3-78a3-0e68-7585ae8e3a19@gutov.dev> <83il8dna30.fsf@gnu.org> <83bke5mhvs.fsf@gnu.org> <83a5tmk79p.fsf@gnu.org> <937d9927-506f-aa36-94e9-3cceb8f629dd@gutov.dev> <83zg1hay6q.fsf@gnu.org> <451d6012-e5ab-df6c-50e3-dac20b91781c@gutov.dev> <83led09dlk.fsf@gnu.org> Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="29290"; mail-complaints-to="usenet@ciao.gmane.io" Cc: 66020@debbugs.gnu.org, stefankangas@gmail.com, monnier@iro.umontreal.ca To: Dmitry Gutov Original-X-From: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane-mx.org@gnu.org Thu Sep 21 17:00:09 2023 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 1qjLA0-0007LR-Jm for geb-bug-gnu-emacs@m.gmane-mx.org; Thu, 21 Sep 2023 17:00:08 +0200 Original-Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1qjL9l-0006As-Rt; Thu, 21 Sep 2023 10:59:53 -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 1qjL9k-0006Ag-LI for bug-gnu-emacs@gnu.org; Thu, 21 Sep 2023 10:59:52 -0400 Original-Received: from debbugs.gnu.org ([2001:470:142:5::43]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1qjL9k-00036e-9X for bug-gnu-emacs@gnu.org; Thu, 21 Sep 2023 10:59:52 -0400 Original-Received: from Debian-debbugs by debbugs.gnu.org with local (Exim 4.84_2) (envelope-from ) id 1qjL9u-0007iM-8t for bug-gnu-emacs@gnu.org; Thu, 21 Sep 2023 11:00:02 -0400 X-Loop: help-debbugs@gnu.org Resent-From: Eli Zaretskii Original-Sender: "Debbugs-submit" Resent-CC: bug-gnu-emacs@gnu.org Resent-Date: Thu, 21 Sep 2023 15:00:02 +0000 Resent-Message-ID: Resent-Sender: help-debbugs@gnu.org X-GNU-PR-Message: followup 66020 X-GNU-PR-Package: emacs X-GNU-PR-Keywords: patch Original-Received: via spool by 66020-submit@debbugs.gnu.org id=B66020.169530839029605 (code B ref 66020); Thu, 21 Sep 2023 15:00:02 +0000 Original-Received: (at 66020) by debbugs.gnu.org; 21 Sep 2023 14:59:50 +0000 Original-Received: from localhost ([127.0.0.1]:34632 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1qjL9i-0007hR-33 for submit@debbugs.gnu.org; Thu, 21 Sep 2023 10:59:50 -0400 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]:57682) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1qjL9f-0007h9-M8 for 66020@debbugs.gnu.org; Thu, 21 Sep 2023 10:59:48 -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 1qjL9O-000337-BG; Thu, 21 Sep 2023 10:59:30 -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=rSfwGjfpGCZpMB1Vt2IAruMLKEuwhJ3wI6RL8LVl8jE=; b=UWssMuD/MqfF +VbG34meYO5/H0TxgQZl8Jzo3UPOscdajcoJzfmgcHK0rd2LE1cKRe8EENg8H597+APyqc+6HM+1g WDVvSmMyDWO+wTONO6HpOdfg0Wb686YeS/zAhyS6qe24ApAcJUxARfkSWzgi1uaU75KtFvQHeTp4Q XlrM/JN5pE5F7BJNkRc/p8lno/Puu0aDc6hDv1LnTfzIrf3BDd0KsZfTwxgbY7JrTXB4lSLlJgmGn MAVBNnJNaQkHSIQTh4/DSbe2+8pOH8MNrtpBJnJt+oyJTvmFTk5mIo3UhPKQSGwkxeElwL+pNa1XH UhuPw480/eVbI8u5GgVNYg==; In-Reply-To: (message from Dmitry Gutov on Thu, 21 Sep 2023 17:37:23 +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-bounces+geb-bug-gnu-emacs=m.gmane-mx.org@gnu.org Xref: news.gmane.io gmane.emacs.bugs:270998 Archived-At: > Date: Thu, 21 Sep 2023 17:37:23 +0300 > Cc: stefankangas@gmail.com, monnier@iro.umontreal.ca, 66020@debbugs.gnu.org > From: Dmitry Gutov > > > How does the throughput depend on this value? If the dependence curve > > plateaus at some lower value, we could use that lower value as a > > "good-enough" default. > > Depends on what we're prepared to call a plateau. Strictly speaking, not > really. But we have a "sweet spot": for the process in my original > benchmark ('find' with lots of output) it seems to be around 1009600. > Here's a table (numbers are different from before because they're > results of (benchmark 5 ...) divided by 5, meaning GC is amortized: > > | 4096 | 0.78 | > | 16368 | 0.69 | > | 40960 | 0.65 | > | 409600 | 0.59 | > | 1009600 | 0.56 | > | 2009600 | 0.64 | > | 4009600 | 0.65 | Not enough data points between 40960 and 409600, IMO. 40960 sounds like a good spot for the default value. > >> And I think we should make the process "remember" the value at its > >> creation either way (something touched on in bug#38561): in bug#55737 we > >> added an fcntl call to make the larger values take effect. But this call > >> is in create_process: so any subsequent increase to a large value of > >> this var won't have effect. > > > > Why would the variable change after create_process? I'm afraid I > > don't understand what issue you are trying to deal with here. > > Well, what could we lose by saving the value of read-process-output-max > in create_process? It's already recorded in the size of the pipe, so why would we need to record it once more? > Currently I suppose one could vary its value while a process is > still running, to implement some adaptive behavior or whatnot. But > that's already semi-broken because fcntl is called in > create_process. I see no reason to support such changes during the process run, indeed.