Files
LocalAI/core/cli
Ettore Di Giacinto 6b4ce58207 feat(cluster): answer presence with four values on the database clock
A worker whose tunnel is gone is not, by that fact, a worker that has left.
Absence is what makes the scheduler stop placing work, reap the worker's rows
and evict its models, and one of those paths runs during inference, so the
deployment needs to tell a worker re-homing between frontend replicas from one
that is really gone before anything acts.

Registry.Presence answers that in one joined statement, with four values and
not a boolean: unknown when there is no row at all (this package cannot tell a
worker that has never dialled from one whose departure aged out, and must not
guess), connected while a live replica holds the tunnel, reconnecting while the
departure is inside the grace, and gone once it is older. Only the last is a
verdict a caller may act on.

Held-ness is asked FIRST and the departure only refines it, in the SQL and
again in the switch that reads it. Every writer here clears disconnected_at in
the statement that writes the owner, but that is a property of these writers
rather than of the table: a replica running a binary from before the column
existed re-claims without clearing the stamp, so during a rolling upgrade a
held row carries an old departure, and a read that consults the stamp first
reports a connected worker as gone for the whole upgrade.

Both windows are computed by the database, for the reason every other window in
this package is: they are compared across replicas, and replicas disagreeing
about whether a worker is gone is the flapping this branch exists to remove. No
behavioural spec can see the difference, since the test container shares the
host clock, so the statement shape is pinned instead.

The grace is an operator's knob, defaulting to twice the worker tunnel's
maximum reconnect backoff. That made the fixed departure retention wrong: an
operator raising the grace past it gets a purge that deletes departures before
the grace elapses, so a worker that is gone reads as unknown forever and
nothing ever reaps it. The retention is now derived from the grace, with the
old constant as its floor.

Assisted-by: Claude Opus 5 [claude-code]
Signed-off-by: Ettore Di Giacinto <mudler@localai.io>
2026-09-02 14:44:50 +00:00
..
2026-03-30 00:47:27 +02:00