Test run for forked PR: Fix ConcurrentHashMap contention#2824
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Replace computeIfAbsent() with putIfAbsent pattern to avoid bin-level locking during value creation. This prevents thread contention issues where threads get stuck in ConcurrentHashMap.helpTransfer() under high concurrency scenarios. The fix uses a double-check pattern: 1. Fast path check with get() 2. Create value outside any lock 3. Atomic putIfAbsent - only one thread wins Trade-off: Under race conditions, multiple threads may create extension instances, but only one wins. This is safe because valueLoader creates empty/stateless instances. This issue was observed in production environments with high thread counts causing application hangs due to ConcurrentHashMap internal contention. Ref: NewRelic Support Case #00311074
Tests verify: - Basic get/remove extension functionality - High concurrency access to same instance key - High concurrency access with different instance keys - Contention scenario with slow value loader These tests confirm the putIfAbsent pattern handles concurrent access without causing thread contention issues.
Codecov Report✅ All modified and coverable lines are covered by tests. Additional details and impacted files@@ Coverage Diff @@
## main #2824 +/- ##
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+ Coverage 70.32% 70.67% +0.34%
- Complexity 10457 10621 +164
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Files 873 881 +8
Lines 42287 42918 +631
Branches 6419 6488 +69
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+ Hits 29740 30332 +592
- Misses 9645 9664 +19
- Partials 2902 2922 +20 ☔ View full report in Codecov by Sentry. 🚀 New features to boost your workflow:
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Relates to #2816
AIT run