Fix circular dependency in Performance Counters on Mac#44661
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jeremydvoss merged 9 commits intoAzure:mainfrom Jan 15, 2026
Merged
Fix circular dependency in Performance Counters on Mac#44661jeremydvoss merged 9 commits intoAzure:mainfrom
jeremydvoss merged 9 commits intoAzure:mainfrom
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...pentelemetry-exporter/azure/monitor/opentelemetry/exporter/_performance_counters/_manager.py
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sdk/monitor/azure-monitor-opentelemetry/azure/monitor/opentelemetry/_configure.py
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Pull request overview
This PR fixes a circular dependency issue in Performance Counters on Mac and other platforms where process I/O counters are unavailable. When _PerformanceCountersManager logged a warning about unavailable I/O counters, it triggered the _PerformanceCountersLogRecordProcessor, which in turn tried to access the not-yet-initialized singleton, causing an infinite lock.
Changes:
- Reordered pipeline setup to initialize metrics (with Performance Counters) before tracing and logging
- Removed non-actionable warning log for unavailable I/O counters on Mac/Linux
- Added test coverage to verify metrics setup occurs before logging and tracing setup
Reviewed changes
Copilot reviewed 4 out of 4 changed files in this pull request and generated 4 comments.
| File | Description |
|---|---|
| azure/monitor/opentelemetry/_configure.py | Moved metrics pipeline setup before tracing and logging to ensure Performance Counters are initialized before processors |
| azure/monitor/opentelemetry/exporter/_performance_counters/_manager.py | Removed non-actionable warning log for unavailable Process I/O Rate counter |
| tests/test_configure.py | Added test assertions to verify metrics setup order precedes logging and tracing |
| CHANGELOG.md | Documented bug fix with placeholder PR number |
sdk/monitor/azure-monitor-opentelemetry/azure/monitor/opentelemetry/_configure.py
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…metry/_configure.py Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>
lzchen
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Description
Issue: langchain-ai/langchain-azure#234
On Mac, the I/O performance counter is not available. This was a known limitation, but the warning log it produced in _PerformanceCountersManager led to a circular dependency. As a log, it triggered the _PerformanceCountersLogRecordProcessor which in turn relied on _PerformanceCountersManager. This led to an infinite lock on the singleton.
To solve this, I moved the Metrics pipeline set up to before Logs and Tracing. This way, the Performance Counters are fully set up before the _PerformanceCountersLogRecordProcessor and _PerformanceCountersSpanProcessor are added. I also removed the log itself because it is not useful as a warning. If a customer is on a Mac or another OS that does not have process I/O, there is nothing for them to do. They will still be able to get all the other Performance Counters.
All SDK Contribution checklist:
General Guidelines and Best Practices
Testing Guidelines