OK
Exclusive placement rights for a set of orgs over specific GPU units of one node, for a term. Scoped to units, not GPU counts, because units are the indivisible allocation primitive.
Absent = open-ended until cancelled
needs-review means the node's GPU topology changed under the reservation: it grants nothing (and withholds its units from everyone) until an operator re-affirms it.
Node topology generation this reservation was written against