Problem
WaitAndWiden treats cache-affinity candidates as unordered peers. A load comparator can move a session between its primary and backup while the primary is still admissible, which weakens cache locality. Queue admissibility also determines when global candidates enter selection, so locality can be abandoned before the request SLO requires it.
Desired behavior
- Treat cache-affinity candidates as an ordered primary and backup.
- Use the backup only when the primary is not admissible.
- Unlock non-affinity candidates only after both affinity candidates are unsuitable.
- Derive the affinity wait budget from the request SLO while leaving enough time for the best cold candidate.
Problem
WaitAndWiden treats cache-affinity candidates as unordered peers. A load comparator can move a session between its primary and backup while the primary is still admissible, which weakens cache locality. Queue admissibility also determines when global candidates enter selection, so locality can be abandoned before the request SLO requires it.
Desired behavior