* master: tell a warming-up Assign client when warm-up ends
During warm-up the master refuses Assign with Unavailable and now attaches
the remaining warm-up as a gRPC RetryInfo detail. RetryWithBackoff may
shorten a backoff step to that hint plus 50 ms, never lengthen it, and only
for a valid, positive hint, so a writer retries right after warm-up ends
instead of up to one backoff step later. The warm-up itself is unchanged.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
* master: jitter the retry-hint slack and hint LookupVolume too
Per review: the slack added to a server hint is now random in
[50ms, 300ms], so clients refused at the same moment do not all retry
in one instant. The warm-up refusal of LookupVolume carries the same
RetryInfo hint as Assign; the masterclient's lookup retry already goes
through RetryWithBackoff, so it lands at warm-up end too.
Tests: the slow guard tests are replaced by one sleep-free table test
of the step logic (zero, negative, huge, malformed, valid and wrapped
hints, a hint longer than the step, none). One timing test of the
shortened step stays, plus a jitter-bounds test and a LookupVolume hint
test. The no-hint control test, which was timing-sensitive, is dropped.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
* master: name the shared warm-up test and file the lookup test by topic
Rename the no-remaining test to TestWarmingUpErrorWithoutRemainingHasNoHint,
since the helper now serves Assign and LookupVolume, and move the
LookupVolume hint test next to the other LookupVolume warm-up tests.
Tests only.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
* util: read the retry hint through ServerStatus
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
* master: bound the warm-up hint in tests by the remaining warm-up around the RPC
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
* test: leave more scheduler margin in the retry-hint timing tests
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
* util, master: trim retry-hint comments
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
* test: widen the retry-hint timing bounds to just under the unhinted wait
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
* test: require a refused warm-up call before the hinted assign retry
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
* test: check the hinted retry wait through a test timer, not the wall clock
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
* test: move the assign warm-up end to 2.6s for more hinted-retry headroom
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
* test: require the hinted retry to wait out its timer
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
---------
Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>
Co-authored-by: Chris Lu <chrislusf@users.noreply.github.com>
