Expand description
Record-number → EntryId lookup as a sorted permutation (ADR-0005): one
id array maintained merge-only, exactly like the sort permutations.
Appends collect in an unmerged tail that lookups scan linearly, and the
end-of-batch merge folds them in sorted order. The keys are the frn
column itself, read through the id indirection — a probe pays one extra
cache miss, which only the USN path and the builder’s parent resolution
ever do (never a search).
Deletions never touch the array: a tombstoned entry simply fails the liveness filter at lookup time. Renames (tombstone + append, same record) and NTFS record reuse therefore leave several ids per key, of which at most one is live — the invariant the mutation API upholds.
Structs§
- FrnIndex 🔒
Functions§
- is_live 🔒