Expand description
Low-level storage primitives.
This module is the bottom of the stack. It is responsible for durable page IO and nothing above it should need to understand file offsets, sidecar files, or crash-recovery record layouts.
The storage layer centers on a single abstraction:
Pager
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buffer free pages durability
pool + file len (rollback/WAL)Responsibilities:
- map logical page ids to bytes on disk or bytes in the in-memory backend;
- allocate, reuse, and retire pages;
- maintain checksum metadata for durable pages;
- implement transaction visibility for rollback-journal and WAL modes;
- report integrity/accounting information upward without knowing what page contents mean.
Extraction boundary:
- external callers should treat
Pagerplus the re-exported page/id types as the entire storage API; - the other submodules are pager internals and are intentionally hidden so the on-disk representation can evolve without leaking into higher layers;
- this is the storage half of the future generic fork point.