fix: reset select() polling backoff after real I/O activity - #292
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fix: reset select() polling backoff after real I/O activity#292toddr-bot wants to merge 1 commit into
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The $not_forever backoff in _select_loop grows from 0.01s to 0.5s when polling for child exits, but it never resets when real I/O occurs. This means harnesses that alternate between active I/O and waiting for children inherit a stale 0.5s backoff, adding unnecessary latency to child reaping. Reset $not_forever to $min_select_timeout whenever select() reports ready file descriptors ($nfound > 0). This ensures each idle period starts with a responsive timeout. Addresses item 2 from GH#291. Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
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What
Reset the
$not_foreverpolling backoff in_select_loopafterselect()reports ready file descriptors.Why
The backoff grows from 0.01s to 0.5s when polling for child exits, but never resets when real I/O occurs (GH#291 item 2). In harnesses that alternate between active I/O and waiting-for-children phases, each idle period inherits the stale 0.5s cap from the previous one, adding unnecessary latency to child reaping.
How
Single line:
$not_forever = $min_select_timeout if $nfound > 0;— placed right after theselect()call, before EINTR handling. Only resets on positive$nfound(actual ready fds), not on errors or EINTR.Testing
Full test suite passes (863 tests). The backoff behavior is internal to the select loop and timing-sensitive, so no new timing-based test was added — the fix is structurally obvious and doesn't change observable API behavior, only responsiveness.
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