Bug #19398: Memory leak in WeakMap

• Status: Closed
• Assignee: -
• Target version: -
• Backport: 2.7: REQUIRED, 3.0: REQUIRED, 3.1: DONE, 3.2: DONE

[peterzhu2118 (Peter Zhu)]

Pull request: https://github.com/ruby/ruby/pull/7223

There's a memory leak in ObjectSpace::WeakMap due to not freeing the struct weakmap. It can be seen in the following script:

100.times do
  10000.times do
    ObjectSpace::WeakMap.new
  end

  # Output the Resident Set Size (memory usage, in KB) of the current Ruby process
  puts `ps -o rss= -p #{$$}`
end

This is the memory usage graph before and after the patch:

[peterzhu2118 (Peter Zhu)]

• Backport changed from 2.7: UNKNOWN, 3.0: UNKNOWN, 3.1: UNKNOWN, 3.2: UNKNOWN to 2.7: REQUIRED, 3.0: REQUIRED, 3.1: REQUIRED, 3.2: REQUIRED

[peterzhu2118 (Peter Zhu)]

• Status changed from Open to Closed

Applied in changeset git|c6f84e918943a0bf8db6fee556fc53180d257510.

---

[Bug #19398] Memory leak in WeakMap

There's a memory leak in ObjectSpace::WeakMap due to not freeing
the struct weakmap. It can be seen in the following script:

100.times do
  10000.times do
    ObjectSpace::WeakMap.new
  end

  # Output the Resident Set Size (memory usage, in KB) of the current Ruby process
  puts `ps -o rss= -p #{$$}`
end

[naruse (Yui NARUSE)]

• Backport changed from 2.7: REQUIRED, 3.0: REQUIRED, 3.1: REQUIRED, 3.2: REQUIRED to 2.7: REQUIRED, 3.0: REQUIRED, 3.1: REQUIRED, 3.2: DONE

ruby_3_2 3426ebd0489654f951a8b92efaf5e72b9f43efab merged revision(s) c6f84e918943a0bf8db6fee556fc53180d257510.

[nagachika (Tomoyuki Chikanaga)]

• Backport changed from 2.7: REQUIRED, 3.0: REQUIRED, 3.1: REQUIRED, 3.2: DONE to 2.7: REQUIRED, 3.0: REQUIRED, 3.1: DONE, 3.2: DONE

ruby_3_1 0d00732d39de1e5ecce738260a1e49d8af52e12a merged revision(s) c6f84e918943a0bf8db6fee556fc53180d257510.