Feature #7022: add event hook for garbage collection

• Status: Closed
• Assignee: authorNari (Narihiro Nakamura)
• Target version: 2.6

[rogerdpack (Roger Pack)]

It would be useful for profilers to have more insight into garbage collection. Feature request: add event hooks for garbage collect start/stop. For the lazy sweep, start and stop events would also be interesting.
Thanks.

[drbrain (Eric Hodel)]

You can't add an event hook for the start of garbage collection. Ruby is out of space for creating the necessary objects.

I think #2565 is a better solution, even though it happens at a lower level.

Also note that there is API for collecting garbage collection and objects pace statistics that can be used for similar purposes.

[rogerdpack (Roger Pack)]

hmm...correct me if I'm wrong (I'm trying to maintain the ruby-prof gem here) will the dtrace probes in #2565 help me if I'm running profiling in windows? Actually if a hook were added for "GC DONE" or the like, I could query using the API at that point, which would probably be enough. Feedbacks?

[headius (Charles Nutter)]

I looked into this on JRuby/JVM last night, and found that they have
recently added a nonstandard API for getting GC notifications as they
happen. And they happen after the GC has occurred. They're
informational.

Would be neat to have something standard in Ruby...especially now that
I know we can implement it (on Java 7u4+ anyway).

FWIW, here's a gist I posted last night that implements
GC::Profiler.report entirely in Ruby using the JVM APIs:

https://gist.github.com/3754108

• Charlie

On Fri, Sep 14, 2012 at 9:13 AM, rogerdpack (Roger Pack)
[e-mail] wrote:

Issue #7022 has been updated by rogerdpack (Roger Pack).

hmm...correct me if I'm wrong (I'm trying to maintain the ruby-prof gem here) will the dtrace probes in #2565 help me if I'm running profiling in windows? Actually if a hook were added for "GC DONE" or the like, I could query using the API at that point, which would probably be enough. Feedbacks?

Feature #7022: add event hook for garbage collection
https://bugs.ruby-lang.org/issues/7022#change-29308

Author: rogerdpack (Roger Pack)
Status: Open
Priority: Normal
Assignee:
Category:
Target version:

It would be useful for profilers to have more insight into garbage collection. Feature request: add event hooks for garbage collect start/stop. For the lazy sweep, start and stop events would also be interesting.
Thanks.

--
http://bugs.ruby-lang.org/

[mame (Yusuke Endoh)]

• Status changed from Open to Assigned
• Assignee set to authorNari (Narihiro Nakamura)
• Target version set to 2.6

On 9/20/12, Charles Oliver Nutter [e-mail] wrote:

I looked into this on JRuby/JVM last night, and found that they have
recently added a nonstandard API for getting GC notifications as they
happen. And they happen after the GC has occurred. They're
informational.

Sweet that's what I have been looking for.

Would be neat to have something standard in Ruby...especially now that
I know we can implement it (on Java 7u4+ anyway).

FWIW, here's a gist I posted last night that implements
GC::Profiler.report entirely in Ruby using the JVM APIs:

https://gist.github.com/3754108

It might be interesting to try and integrate the ruby-prof gem more
with native jruby sometime.
Cheers!
-roger-

[authorNari (Narihiro Nakamura)]

• Status changed from Assigned to Closed

Fixed at r40940.
(ticket is here: https://bugs.ruby-lang.org/issues/8107)

Thank you.