From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on dcvr.yhbt.net X-Spam-Level: X-Spam-Status: No, score=-2.6 required=3.0 tests=AWL,BAYES_00, DKIM_ADSP_CUSTOM_MED,FORGED_GMAIL_RCVD,FREEMAIL_FORGED_FROMDOMAIN, FREEMAIL_FROM,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, RCVD_IN_DNSWL_MED,SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY shortcircuit=no autolearn=no autolearn_force=no version=3.4.2 Received: from neon.ruby-lang.org (neon.ruby-lang.org [221.186.184.75]) by dcvr.yhbt.net (Postfix) with ESMTP id 740491F4B4 for ; Tue, 30 Mar 2021 19:16:15 +0000 (UTC) Received: from neon.ruby-lang.org (localhost [IPv6:::1]) by neon.ruby-lang.org (Postfix) with ESMTP id 871CC120E0E; Wed, 31 Mar 2021 04:15:13 +0900 (JST) Received: from xtrwkhkc.outbound-mail.sendgrid.net (xtrwkhkc.outbound-mail.sendgrid.net [167.89.16.28]) by neon.ruby-lang.org (Postfix) with ESMTPS id 04F39120E0D for ; Wed, 31 Mar 2021 04:15:10 +0900 (JST) Received: by filterdrecv-p3iad2-7d7c446bd4-n48fk with SMTP id filterdrecv-p3iad2-7d7c446bd4-n48fk-19-606378F7-7B 2021-03-30 19:16:07.599332422 +0000 UTC m=+607392.515403741 Received: from herokuapp.com (unknown) by ismtpd0129p1iad2.sendgrid.net (SG) with ESMTP id PfQy83bWTkSzemkVJsZ56Q for ; Tue, 30 Mar 2021 19:16:07.510 +0000 (UTC) Date: Tue, 30 Mar 2021 19:16:07 +0000 (UTC) From: eregontp@gmail.com Message-ID: References: Mime-Version: 1.0 X-Redmine-MailingListIntegration-Message-Ids: 79143 X-Redmine-Project: ruby-master X-Redmine-Issue-Tracker: Feature X-Redmine-Issue-Id: 17762 X-Redmine-Issue-Author: mame X-Redmine-Sender: Eregon X-Mailer: Redmine X-Redmine-Host: bugs.ruby-lang.org X-Redmine-Site: Ruby Issue Tracking System X-Auto-Response-Suppress: All Auto-Submitted: auto-generated X-SG-EID: =?us-ascii?Q?KippOI8ZHtTweq7XfQzW93937kJ4QNWwSBuHnaMEcr1xSeOkipcqXK8mjAhJDN?= =?us-ascii?Q?Yzazre8CV0YVJ6f13QdSwghZQoaFUcTJHLWkkCd?= =?us-ascii?Q?Ka3RYAdO4F0xLyH80cOfyCo0Bwa4w4OpBI6UwPV?= =?us-ascii?Q?UJuwdBrc+wrLhfKJbqJv7hOuDElvD0w0ICV1IGZ?= =?us-ascii?Q?vdslrOeKSWjTtLfUsdMnhJRfR1q6nI4Fy0nUNtj?= =?us-ascii?Q?7Zmf2LwkbQKxKoI9M=3D?= To: ruby-core@ruby-lang.org X-Entity-ID: b/2+PoftWZ6GuOu3b0IycA== X-ML-Name: ruby-core X-Mail-Count: 103108 Subject: [ruby-core:103108] [Ruby master Feature#17762] A simple way to trace object allocation X-BeenThere: ruby-core@ruby-lang.org X-Mailman-Version: 2.1.15 Precedence: list Reply-To: Ruby developers List-Id: Ruby developers List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: ruby-core-bounces@ruby-lang.org Sender: "ruby-core" Issue #17762 has been updated by Eregon (Benoit Daloze). `require "objspace/trace"` automatically starting tracing seems dangerous, there is a pretty big performance penalty to enable it. So I think the message on stderr is needed, and maybe it should be more explicit like `require "objspace/start_tracing"`. There might be different sorts of tracing so ultimately I feel `ObjectSpace.trace_object_allocations_start` is long but is clear and well-named IMHO. byroot (Jean Boussier) wrote in #note-2: > I'm not too sure about that one. I suppose it's fine, but I'm not always in a situation where `p` is usable. Would `Object#allocation_source` be acceptable? How about `ObjectSpace.allocation_source(obj)`? `Object#allocation_source` wouldn't work for BasicObject and it would pollute Object/Kernel which seems suboptimal to me. ---------------------------------------- Feature #17762: A simple way to trace object allocation https://bugs.ruby-lang.org/issues/17762#change-91173 * Author: mame (Yusuke Endoh) * Status: Open * Priority: Normal ---------------------------------------- How about having a short hand to `ObjectSpace.trace_object_allocations_start`, `ObjectSpace.allocation_sourcefile` and `ObjectSpace.allocation_sourceline`? They are a very powerful tool for debugging and code-reading which allows us to identify an allocation site of an object. Though they are never lightweight, they are the last resort when you try debugging code written by someone else. However, the names are too long for me to remember and to type. Whenever I want to use them, I have to google, copy and paste the names. ## Proposal To enable trace allocations: ``` require "objspace/trace" #=> objspace/trace is enabled ``` To show the allocation site of an object: ``` p obj #=> # @ (file.rb):(lineno) ``` ## Example ``` require "objspace/trace" require "active_support/all" p ActiveSupport::VERSION::STRING #=> "6.1.3.1" @ /home/mame/work/ruby/local/lib/ruby/gems/3.1.0/gems/activesupport-6.1.3.1/lib/active_support/gem_version.rb:15 ``` ## Discussion I've attached a simple patch that is originally authored by @ko1 . * Is the message `objspace/trace is enabled` needed or not? * To stop the trace, you need to use `Object.trace_object_allocations_stop`. But, I guess that it is rare that we need to stop it during debugging. * Is it too radical to redefine `Kernel#p`? I think that it is good enough for many cases. When it matters, the original APIs (`ObjectSpace.trace_object_allocations_start`, ...) can be used. ---Files-------------------------------- objspace-trace.patch (631 Bytes) -- https://bugs.ruby-lang.org/