Module budget 

Shared reservation arithmetic. Currently the page arena uses this ledger; it is not a whole-process RSS cap. Constrained stores additionally bound WAL/record sizes and allocator bookkeeping counts through ResourceLimits. Exhaustion is fallible, including arithmetic overflow.

Structs

MemoryBudget

Reservation

class is not read today – Drop only needs bytes to release the reservation – but every reserve call already names one, so it is carried here rather than discarded, for a future per-class usage breakdown or a same-class-releases-what-it-reserved assertion.

Enums

Class