Bug #1152: profiler.rb is not concurrent-execution threadsafe

• Status: Closed
• Assignee: nobu (Nobuyoshi Nakada)
• Target version: 2.0.0
• ruby -v: all versions 1.8.6 and up

[headius (Charles Nutter)]

=begin
The library profiler.rb uses class variables to store data without wrapping them in mutexes. On current C Ruby, this may only rarely cause a problem, but as more and more code is allowed to run in parallel it's going to lead to issues. If I or other JRuby community members have a chance, we'll try to make it thread-safe, but I wanted to file this issue to ensure it's out there.

The library is also largely unchanged in 1.9.1.

See http://jira.codehaus.org/browse/JRUBY-2133 for the (admittedly sparse) JRuby issue.
=end

[jabley (James Abley)]

• File 1152.patch 1152.patch added

=begin
Sample patch attached for discussion. There are style and best
practice issues with this patch due to my lack of ruby experience.
Please forgive and be so kind as to suggest improvements.

It is intended to highlight some of the areas that must be considered
when making the change to provide thread-safe profiling.

The patch alters the code to make the capture of the data thread-safe
AFAICT. There may be some issues with the data fields / calculations.
I wasn't completely clear what each field in the array was supposed to
be storing. The main issue unresolved by this patch is how best to
present the information.

I've opted for showing information per-thread and a summary as well.

• Should there be a version number outputted, in case downstream tools
  are doing something with this information?
• Any comments on how the information is being presented??
• Should profiling be configurable, so that it may not show output per
  thread, etc.

=end

[jabley (James Abley)]

• File 1152-2009-03-09.patch 1152-2009-03-09.patch added

=begin
Whoops. Wrong patch attached. Updated version.
=end

[akr (Akira Tanaka)]

• Project changed from 8 to Ruby

[naruse (Yui NARUSE)]

• Status changed from Open to Assigned
• Assignee set to shugo (Shugo Maeda)

[shugo (Shugo Maeda)]

• Assignee changed from shugo (Shugo Maeda) to matz (Yukihiro Matsumoto)

I'm not the maintainer of profiler.rb. According to git blame,
it seems to be written by Matz and ocean, so I assign this ticket
to Matz.

[ko1 (Koichi Sasada)]

• Assignee changed from matz (Yukihiro Matsumoto) to ko1 (Koichi Sasada)

I take it.

[ko1 (Koichi Sasada)]

• Category set to lib
• Target version set to 2.0.0

[ko1 (Koichi Sasada)]

• Assignee changed from ko1 (Koichi Sasada) to nobu (Nobuyoshi Nakada)

nobu, could you check it?

[nobu (Nobuyoshi Nakada)]

• Status changed from Assigned to Closed
• % Done changed from 0 to 100

This issue was solved with changeset r38576.
Charles, thank you for reporting this issue.
Your contribution to Ruby is greatly appreciated.
May Ruby be with you.

---

profiler.rb: concurrent-execution

• lib/profiler.rb (Profiler__::PROFILE_PROC, print_profile): store
  profile data per threads for concurrent-execution.
  [ruby-core:22046] [Bug #1152]

[nobu (Nobuyoshi Nakada)]

profiler.rb: concurrent-execution

• lib/profiler.rb (Profiler__::PROFILE_PROC, print_profile): store
  profile data per threads for concurrent-execution.
  [ruby-core:22046] [Bug #1152]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@38576 b2dd03c8-39d4-4d8f-98ff-823fe69b080e