Bound close(timeout) around a pending cancel - #1361
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elprans merged 3 commits intoSep 21, 2026
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close() awaited cancel_waiter with no timeout, and connection_lost only resolved waiter. A frozen server left close() hanging even after the socket dropped. Fixes MagicStack#1356
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Added a bit more robustness to cancellation drainage and made it so that cancellation shares the close operation timeout budget.
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Fixes #1356.
close(timeout=)waits forcancel_waiterbefore it appliestimeout. That future is only completed when ReadyForQuery arrives on the original socket._on_connection_lostresolveswaiterand leaves the cancel futures pending, so a frozen server (or a pooler that then drops the client) can leaveclose()hung forever.SQLAlchemy's asyncpg dialect hits this when it invalidates a connection after
TimeoutErrorwithclose(timeout=2).The cancel wait now uses the same timeout, a lost transport completes the cancel futures, and
abort()still drops the socket ifclose()already setclosing.