Never schedule stdin feeds or child kill timers on the global queue - #4
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DispatchQueue.global() is non-overcommit, so on a low-core machine the blocked callers themselves can starve it: the -C stdin feeder never runs, the command never sees EOF on stdin, and the caller waits on it forever. Three such tests wedged the whole suite on the 3-vCPU CI runner for 6 hours. The kill timers rode the same pool, so a timeout could silently never fire exactly when a child hung. Feed stdin from a dedicated thread and run the timers on a private queue. Fixes #3 Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
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DispatchQueue.global() is non-overcommit, so on a low-core machine the blocked callers themselves can starve it: the -C stdin feeder never runs, the command never sees EOF on stdin, and the caller waits on it forever.
Three such tests wedged the test suite, causing the deadlock bug flagged in #3. This PR fixes that by feeding stdin from a dedicated thread and running the timers on a private queue.
Fixes #3