segmentNumbers

The segments the version this view pinned is made of.

The universe a reader at this snapshot may reason about, and it is not the store's live set. A compaction installs a new version and retires the old one, but this snapshot still holds — and still reads through — the segments it pinned. A caller that asked DocumentStore.liveSegmentNumbers instead and then scanned those numbers would scan files this view cannot see and skip files it can, which for a query means documents silently missing from an answer.

So a layer that partitions the work of a read — an index answering for some segments and DocumentStore.scanSegments reading the rest — must take the partition over this set.