test_in_monitor_agent: ensure to shutdown plugin instances#5323
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Signed-off-by: Shizuo Fujita <fujita@clear-code.com>
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**Which issue(s) this PR fixes**:
Fixes #
**What this PR does / why we need it**:
Fix thread and resource leaks in `test_in_monitor_agent.rb` by ensuring
proper shutdown sequences for plugin instances.
Currently, the test cases for `in_monitor_agent` start plugin instances
but do not properly shut them down at the end. Because this plugin
utilizes helpers (such as `http_server` and `timer`), bypassing the
proper `stop`/`shutdown` lifecycle leaves their background threads
running indefinitely.
As a result, executing the test file leaves many orphaned threads, which
could lead to test hangs or resource exhaustion in CI environments.
```
$ ruby -Ilib:test -e "at_exit { puts '--- Thread count at exit: ' + Thread.list.size.to_s; pp Thread.list }; require './test/plugin/test_in_monitor_agent.rb'"
...
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
24 tests, 42 assertions, 0 failures, 0 errors, 0 pendings, 0 omissions, 0 notifications
100% passed
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
5.09 tests/s, 8.90 assertions/s
--- Thread count at exit: 34
[#<Thread:0x00007f35334b7f48 run>,
#<Thread:0x00007f3516211f90@event_loop /home/watson/src/fluentd/lib/fluent/plugin_helper/thread.rb:70 sleep>,
#<Thread:0x00007f351620cd10@in_monitor_http_server_helper /home/watson/src/fluentd/lib/fluent/plugin_helper/thread.rb:70 sleep>,
#<Thread:0x00007f3516e1e9c8@event_loop /home/watson/src/fluentd/lib/fluent/plugin_helper/thread.rb:70 sleep>,
#<Thread:0x00007f3516e1a300@in_monitor_http_server_helper /home/watson/src/fluentd/lib/fluent/plugin_helper/thread.rb:70 sleep>,
#<Thread:0x00007f3516e74620@flush_thread_0 /home/watson/src/fluentd/lib/fluent/plugin_helper/thread.rb:70 sleep>,
#<Thread:0x00007f3516e730b8@enqueue_thread /home/watson/src/fluentd/lib/fluent/plugin_helper/thread.rb:70 sleep>,
#<Thread:0x00007f351705df40@event_loop /home/watson/src/fluentd/lib/fluent/plugin_helper/thread.rb:70 sleep>,
#<Thread:0x00007f351713fc88@in_monitor_http_server_helper /home/watson/src/fluentd/lib/fluent/plugin_helper/thread.rb:70 sleep>,
#<Thread:0x00007f351409ab78@event_loop /home/watson/src/fluentd/lib/fluent/plugin_helper/thread.rb:70 sleep>,
#<Thread:0x00007f3514099160@in_monitor_http_server_helper /home/watson/src/fluentd/lib/fluent/plugin_helper/thread.rb:70 sleep>,
#<Thread:0x00007f35140bdb00@Timeout stdlib thread /home/watson/.rbenv/versions/4.0.2/lib/ruby/4.0.0/timeout.rb:87 sleep_forever>,
#<Thread:0x00007f3516e18de8@event_loop /home/watson/src/fluentd/lib/fluent/plugin_helper/thread.rb:70 sleep>,
#<Thread:0x00007f351623b7c8@in_monitor_http_server_helper /home/watson/src/fluentd/lib/fluent/plugin_helper/thread.rb:70 sleep>,
#<Thread:0x00007f3516076730@event_loop /home/watson/src/fluentd/lib/fluent/plugin_helper/thread.rb:70 sleep>,
#<Thread:0x00007f3516072b08@in_monitor_http_server_helper /home/watson/src/fluentd/lib/fluent/plugin_helper/thread.rb:70 sleep>,
#<Thread:0x00007f3514059c18@event_loop /home/watson/src/fluentd/lib/fluent/plugin_helper/thread.rb:70 sleep>,
#<Thread:0x00007f35140566d0@in_monitor_http_server_helper /home/watson/src/fluentd/lib/fluent/plugin_helper/thread.rb:70 sleep>,
#<Thread:0x00007f35162ce848@event_loop /home/watson/src/fluentd/lib/fluent/plugin_helper/thread.rb:70 sleep>,
#<Thread:0x00007f35162c7cc8@in_monitor_http_server_helper /home/watson/src/fluentd/lib/fluent/plugin_helper/thread.rb:70 sleep>,
#<Thread:0x00007f35160789b8@event_loop /home/watson/src/fluentd/lib/fluent/plugin_helper/thread.rb:70 sleep>,
#<Thread:0x00007f35160766b8@in_monitor_http_server_helper /home/watson/src/fluentd/lib/fluent/plugin_helper/thread.rb:70 sleep>,
#<Thread:0x00007f35172c1020@event_loop /home/watson/src/fluentd/lib/fluent/plugin_helper/thread.rb:70 sleep>,
#<Thread:0x00007f35172e63e8@in_monitor_http_server_helper /home/watson/src/fluentd/lib/fluent/plugin_helper/thread.rb:70 sleep>,
#<Thread:0x00007f34f792ef40@event_loop /home/watson/src/fluentd/lib/fluent/plugin_helper/thread.rb:70 sleep>,
#<Thread:0x00007f34f792d230@in_monitor_http_server_helper /home/watson/src/fluentd/lib/fluent/plugin_helper/thread.rb:70 sleep>,
#<Thread:0x00007f35172cc4e8@event_loop /home/watson/src/fluentd/lib/fluent/plugin_helper/thread.rb:70 sleep>,
#<Thread:0x00007f35172c0350@in_monitor_http_server_helper /home/watson/src/fluentd/lib/fluent/plugin_helper/thread.rb:70 sleep>,
#<Thread:0x00007f34f7ad76a8@event_loop /home/watson/src/fluentd/lib/fluent/plugin_helper/thread.rb:70 sleep>,
#<Thread:0x00007f34f7ad53f8@in_monitor_http_server_helper /home/watson/src/fluentd/lib/fluent/plugin_helper/thread.rb:70 sleep>,
#<Thread:0x00007f35160808e8@event_loop /home/watson/src/fluentd/lib/fluent/plugin_helper/thread.rb:70 sleep>,
#<Thread:0x00007f351621c530@in_monitor_http_server_helper /home/watson/src/fluentd/lib/fluent/plugin_helper/thread.rb:70 sleep>,
#<Thread:0x00007f34f7902918@event_loop /home/watson/src/fluentd/lib/fluent/plugin_helper/thread.rb:70 sleep>,
#<Thread:0x00007f34f796e848@in_monitor_http_server_helper /home/watson/src/fluentd/lib/fluent/plugin_helper/thread.rb:70 sleep>]
```
**Docs Changes**:
N/A
**Release Note**:
N/A
Signed-off-by: Shizuo Fujita <fujita@clear-code.com>
Signed-off-by: github-actions[bot] <github-actions[bot]@users.noreply.github.com>
Watson1978
added a commit
that referenced
this pull request
Apr 20, 2026
…tances (#5323) (#5341) **Which issue(s) this PR fixes**: Backport #5323 Fixes # **What this PR does / why we need it**: Fix thread and resource leaks in `test_in_monitor_agent.rb` by ensuring proper shutdown sequences for plugin instances. Currently, the test cases for `in_monitor_agent` start plugin instances but do not properly shut them down at the end. Because this plugin utilizes helpers (such as `http_server` and `timer`), bypassing the proper `stop`/`shutdown` lifecycle leaves their background threads running indefinitely. As a result, executing the test file leaves many orphaned threads, which could lead to test hangs or resource exhaustion in CI environments. ``` $ ruby -Ilib:test -e "at_exit { puts '--- Thread count at exit: ' + Thread.list.size.to_s; pp Thread.list }; require './test/plugin/test_in_monitor_agent.rb'" ... ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ 24 tests, 42 assertions, 0 failures, 0 errors, 0 pendings, 0 omissions, 0 notifications 100% passed ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ 5.09 tests/s, 8.90 assertions/s --- Thread count at exit: 34 [#<Thread:0x00007f35334b7f48 run>, #<Thread:0x00007f3516211f90@event_loop /home/watson/src/fluentd/lib/fluent/plugin_helper/thread.rb:70 sleep>, #<Thread:0x00007f351620cd10@in_monitor_http_server_helper /home/watson/src/fluentd/lib/fluent/plugin_helper/thread.rb:70 sleep>, #<Thread:0x00007f3516e1e9c8@event_loop /home/watson/src/fluentd/lib/fluent/plugin_helper/thread.rb:70 sleep>, #<Thread:0x00007f3516e1a300@in_monitor_http_server_helper /home/watson/src/fluentd/lib/fluent/plugin_helper/thread.rb:70 sleep>, #<Thread:0x00007f3516e74620@flush_thread_0 /home/watson/src/fluentd/lib/fluent/plugin_helper/thread.rb:70 sleep>, #<Thread:0x00007f3516e730b8@enqueue_thread /home/watson/src/fluentd/lib/fluent/plugin_helper/thread.rb:70 sleep>, #<Thread:0x00007f351705df40@event_loop /home/watson/src/fluentd/lib/fluent/plugin_helper/thread.rb:70 sleep>, #<Thread:0x00007f351713fc88@in_monitor_http_server_helper /home/watson/src/fluentd/lib/fluent/plugin_helper/thread.rb:70 sleep>, #<Thread:0x00007f351409ab78@event_loop /home/watson/src/fluentd/lib/fluent/plugin_helper/thread.rb:70 sleep>, #<Thread:0x00007f3514099160@in_monitor_http_server_helper /home/watson/src/fluentd/lib/fluent/plugin_helper/thread.rb:70 sleep>, #<Thread:0x00007f35140bdb00@Timeout stdlib thread /home/watson/.rbenv/versions/4.0.2/lib/ruby/4.0.0/timeout.rb:87 sleep_forever>, #<Thread:0x00007f3516e18de8@event_loop /home/watson/src/fluentd/lib/fluent/plugin_helper/thread.rb:70 sleep>, #<Thread:0x00007f351623b7c8@in_monitor_http_server_helper /home/watson/src/fluentd/lib/fluent/plugin_helper/thread.rb:70 sleep>, #<Thread:0x00007f3516076730@event_loop /home/watson/src/fluentd/lib/fluent/plugin_helper/thread.rb:70 sleep>, #<Thread:0x00007f3516072b08@in_monitor_http_server_helper /home/watson/src/fluentd/lib/fluent/plugin_helper/thread.rb:70 sleep>, #<Thread:0x00007f3514059c18@event_loop /home/watson/src/fluentd/lib/fluent/plugin_helper/thread.rb:70 sleep>, #<Thread:0x00007f35140566d0@in_monitor_http_server_helper /home/watson/src/fluentd/lib/fluent/plugin_helper/thread.rb:70 sleep>, #<Thread:0x00007f35162ce848@event_loop /home/watson/src/fluentd/lib/fluent/plugin_helper/thread.rb:70 sleep>, #<Thread:0x00007f35162c7cc8@in_monitor_http_server_helper /home/watson/src/fluentd/lib/fluent/plugin_helper/thread.rb:70 sleep>, #<Thread:0x00007f35160789b8@event_loop /home/watson/src/fluentd/lib/fluent/plugin_helper/thread.rb:70 sleep>, #<Thread:0x00007f35160766b8@in_monitor_http_server_helper /home/watson/src/fluentd/lib/fluent/plugin_helper/thread.rb:70 sleep>, #<Thread:0x00007f35172c1020@event_loop /home/watson/src/fluentd/lib/fluent/plugin_helper/thread.rb:70 sleep>, #<Thread:0x00007f35172e63e8@in_monitor_http_server_helper /home/watson/src/fluentd/lib/fluent/plugin_helper/thread.rb:70 sleep>, #<Thread:0x00007f34f792ef40@event_loop /home/watson/src/fluentd/lib/fluent/plugin_helper/thread.rb:70 sleep>, #<Thread:0x00007f34f792d230@in_monitor_http_server_helper /home/watson/src/fluentd/lib/fluent/plugin_helper/thread.rb:70 sleep>, #<Thread:0x00007f35172cc4e8@event_loop /home/watson/src/fluentd/lib/fluent/plugin_helper/thread.rb:70 sleep>, #<Thread:0x00007f35172c0350@in_monitor_http_server_helper /home/watson/src/fluentd/lib/fluent/plugin_helper/thread.rb:70 sleep>, #<Thread:0x00007f34f7ad76a8@event_loop /home/watson/src/fluentd/lib/fluent/plugin_helper/thread.rb:70 sleep>, #<Thread:0x00007f34f7ad53f8@in_monitor_http_server_helper /home/watson/src/fluentd/lib/fluent/plugin_helper/thread.rb:70 sleep>, #<Thread:0x00007f35160808e8@event_loop /home/watson/src/fluentd/lib/fluent/plugin_helper/thread.rb:70 sleep>, #<Thread:0x00007f351621c530@in_monitor_http_server_helper /home/watson/src/fluentd/lib/fluent/plugin_helper/thread.rb:70 sleep>, #<Thread:0x00007f34f7902918@event_loop /home/watson/src/fluentd/lib/fluent/plugin_helper/thread.rb:70 sleep>, #<Thread:0x00007f34f796e848@in_monitor_http_server_helper /home/watson/src/fluentd/lib/fluent/plugin_helper/thread.rb:70 sleep>] ``` **Docs Changes**: N/A **Release Note**: N/A Signed-off-by: Shizuo Fujita <fujita@clear-code.com> Signed-off-by: github-actions[bot] <github-actions[bot]@users.noreply.github.com> Co-authored-by: Shizuo Fujita <fujita@clear-code.com>
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Which issue(s) this PR fixes:
Fixes #
What this PR does / why we need it:
Fix thread and resource leaks in
test_in_monitor_agent.rbby ensuring proper shutdown sequences for plugin instances.Currently, the test cases for
in_monitor_agentstart plugin instances but do not properly shut them down at the end. Because this plugin utilizes helpers (such ashttp_serverandtimer), bypassing the properstop/shutdownlifecycle leaves their background threads running indefinitely.As a result, executing the test file leaves many orphaned threads, which could lead to test hangs or resource exhaustion in CI environments.
Docs Changes:
N/A
Release Note:
N/A