How do you diagnose event-loop stalls, orphaned tasks, and async resource leaks?

Combines asyncio debug evidence, task inspection, warnings, profiling, and capacity signals.

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I enable asyncio debug mode in a controlled environment, configure slow-callback reporting, and surface ResourceWarning messages. During a stall I inspect task names and stacks, event-loop lag, CPU profiles, and downstream timings. Orphaned-task warnings, never-awaited coroutine warnings, unclosed transports, and task exceptions that were never retrieved point to ownership or cleanup defects rather than random runtime noise.

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Combines asyncio debug evidence, task inspection, warnings, profiling, and capacity signals.

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Combines asyncio debug evidence, task inspection, warnings, profiling, and capacity signals.
I enable asyncio debug mode in a controlled environment, configure slow-callback reporting, and surface ResourceWarning messages. During a stall I inspect task names and stacks, event-loop lag, CPU profiles, and downstream timings. Orphaned-task warnings, never-awaited coroutine warnings, unclosed transports, and task exceptions that were never retrieved point to ownership or cleanup defects rather than random runtime noise.
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I correlate the first stall with synchronous code on the loop, executor queueing, oversized serialization, busy polling, lock waits, or a flood of ready tasks. For memory growth I compare active task counts and retained stacks over time and look for tasks waiting forever on queues or events. Reproduction uses bounded test traffic and injected slow dependencies so evidence stays attributable.

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Treating every stall as high CPU
Ignoring never-retrieved exceptions
Enabling expensive debug evidence everywhere indefinitely

How do you diagnose event-loop stalls, orphaned tasks, and async resource leaks?

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