System.Threading.Tests.MutexTests.CrossProcess_NamedMutex_ConcurrentCreateOrOpen failing in CI

[jakobbotsch]

Build Information

Build: https://dev.azure.com/dnceng-public/cbb18261-c48f-4abb-8651-8cdcb5474649/_build/results?buildId=1488179
Build error leg or test failing: System.Threading.Tests.MutexTests.CrossProcess_NamedMutex_ConcurrentCreateOrOpen
Pull request: #129894

Error Message

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Fill the error message using step by step known issues guidance.

{
  "ErrorMessage": "System.Threading.Tests.MutexTests.CrossProcess_NamedMutex_ConcurrentCreateOrOpen(currentUserOnly: True, currentSessionOnly: False) [FAIL]",
  "ErrorPattern": "",
  "BuildRetry": false,
  "ExcludeConsoleLog": false
}

Looks like a new test from #129923, cc @jkotas

Known issue validation

Build: 🔎 https://dev.azure.com/dnceng-public/public/_build/results?buildId=1488179
Error message validated: [System.Threading.Tests.MutexTests.CrossProcess_NamedMutex_ConcurrentCreateOrOpen(currentUserOnly: True, currentSessionOnly: False) [FAIL]]
Result validation: ✅ Known issue matched with the provided build.
Validation performed at: 6/30/2026 9:01:11 PM UTC

Report

Build	Repository	Test	Pull Request
1488560	dotnet/runtime	System.Threading.Tests.MutexTests.CrossProcess_NamedMutex_ConcurrentCreateOrOpen	#130006
1488548	dotnet/runtime	System.Threading.Tests.MutexTests.CrossProcess_NamedMutex_ConcurrentCreateOrOpen
1488179	dotnet/runtime	System.Threading.Tests.MutexTests.CrossProcess_NamedMutex_ConcurrentCreateOrOpen	#129894

Summary

24-Hour Hit Count	7-Day Hit Count	1-Month Count
3	3	3

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