The detection waiter selects on the request's completion channel and on
the stream's done channel. A worker that finishes a scan and then drops
its stream (a restart right after a scan is the usual shape) buffers the
completion into the request before the receive loop sees the EOF, and
the stream's cleanup then closes done. A waiter that reaches its select
after both are ready can take the disconnect branch, and a completed
detection, proposals included, is failed as "detection worker
disconnected" and retried or recorded as an error.
When the stream closes or the liveness tick finds the worker gone, the
waiter now takes a completion that is already queued and returns it as
the success it is; the detector lease still goes, since the worker that
answered is unreachable. A ctx that ended keeps its meaning: the caller
stopped wanting the answer. The wait loop moves into
awaitDetectionOutcome so a test can hand it both channels already
ready; before this change that test fails on about half its runs. A
completion that lands after the waiter gave up stays unmatched, since
the request's pending entry is gone and the next request has a new id.
* admin: keep a reconnected plugin worker registered when its old stream unwinds
cleanupSession removed whatever session was registered under the worker
ID, so a worker that reconnected while its previous stream was still
unwinding lost the new session and its registry entry to the old
stream's deferred cleanup. Tie cleanup to the stream that is ending and
publish the new stream before the registry upsert so a lingering
predecessor sees itself superseded.
* admin: fail an in-flight detection when its worker disconnects
RunDetectionWithReport waited only on the caller's context and the
DetectionComplete channel, so a detection whose worker stream ended
mid-request could only finish by timeout. On a customer cluster a
planned restart of ec-vacuum-1 during an ec_vacuum detection left the
default lane in 'detecting' with every execution slot idle until the
3600s detection timeout, blocking every job type in that lane.
Bind the request to the stream it was sent on and fail the detection
as soon as that stream closes, whether by disconnect or by a reconnect
that replaced the session. A liveness tick also fails it once the
registry no longer considers the worker available (heartbeat stale),
sending a cancel in that case because the stream may still be open.
The detector lease is dropped so the next pick starts fresh, and a
'disconnected' detector activity is recorded. WorkerDisconnectForTest
now goes through the real session cleanup.
* admin: retry a scheduled detection once when its detector drops
When a detection fails because its worker disconnected, pick a detector
again and retry once within the same iteration while the job type's
runtime budget allows, instead of giving the whole cycle up. Any other
failure, or a failed retry, ends the run as before and the lane moves
on; the next cycle re-detects anyway.
* admin: register a plugin worker's hello and stream as one
step
WorkerStream published the stream under sessionsMu but ran the registry
upsert after releasing it, so two concurrent streams for one worker ID
could publish their hellos in the opposite order from their sessions:
the registry then described the older hello's capabilities while only
the newer stream was sendable, and detector picks routed on them.
registerSession upserts the hello and installs the stream under one
sessionsMu critical section, and a hello or heartbeat arriving on a
stream that is no longer the registered one is dropped instead of
rewriting the live stream's entry.
* admin: steer a detection retry off the stream that dropped
The retry picked while the lost worker could still be in the registry:
cleanupSession closed done before taking the registry entry down, and a
stream closed by a reconnect keeps its entry on purpose. The lost worker
ranks first on free slots, so the single retry went back to it and
failed on send while a healthy worker sat idle.
The disconnect error now carries the stream it came from and the retry
picks around it; pickDetector only returns workers whose current stream
is open, excluding registry entries whose stream is closed; and
cleanupSession removes the registry entry before closing done, so a
waiter woken by the closure never sees the dead worker as a candidate.
Chris Lu