Module backend 

Structs

BackendDiskStats

Point-in-time disk write-path counters (cumulative since process start). foyer-independent so the trait stays buildable without the foyer feature; None for backends with no disk tier (e.g. in-memory).

Enums

FillHint

Hints the backend’s fill priority: prefetch fills should not evict hot demand data from a bounded cache tier.

Traits

RangeCacheBackend