Timeline

ReadFileContext, ReadFileAtContext, AnnotateContext and DiffContext take RequiredContentOpts and, when a read needs content a horizon store does not hold, fetch exactly the artifacts it names from the peer and read again (draft-fossil-horizon-00 4.4): the payload, and on a structural store first the check-in's manifest, baseline and nodes. The store cone and its horizon do not move; fetched artifacts are held content.

Reads now refuse with content.MissingBelowHorizon, which matches ErrBelowHorizon and names the horizon. Annotate gathers every missing version along its walk into one round and Diff both sides; a read over one round's gimme budget is refused naming DeepenHorizon.

Closes #489 leaf check-in: 8821596379 user: [email protected] tags: feat/demand-fetch-reads, main, trunk

A hosted SQLite that caps value size (a Durable Object's 2 MB) cannot hold a large file's stored blob in one blob.content value. With the new db.DriverConfig.MaxValueBytes set, a stored value over the limit is written in 1,000,000-byte parts to blobpart(rid, seq, content), created on first use, leaving blob.content NULL and blob.size the expanded length, so phantoms (size < 0) stay unambiguous. Chunking sits below compression: hashes, deltas and the wire format are unchanged.

internal/blob owns the seam (ReadStored, WriteStored, InsertStored, StoredHead, DropStored, SweepParts and two scan expressions), and every direct reader or writer of blob.content now goes through it: delta rewrite and undelta, receive, clone send and walk, compaction, sparse demotion, seed drop, shun purge, horizon cost and cone preparation.

Zero, the default, keeps every value inline and creates no table, so local stores stay byte-identical. A store with blobpart rows is not readable by stock fossil; enable it only for hosted backends.

Closes #459 check-in: 1fd12b3ed3 user: [email protected] tags: feat/chunked-blobs, main, trunk

conformance: HZ-4.1-1 scoped to zit and go-libfossil origins check-in: 1455a3803e user: [email protected] tags: main, trunk

The origin classification memo now reads the F cards of every tree in the store once, with its references, and extends them by appended check-ins (draft-fossil-horizon-00 §6.2, HZ-6.2-10). Blob names are interned to uint32 ids, each tree's file set is a sorted delta-varint id list, and a full manifest is kept as its symmetric difference from the previous full manifest read, at most 15 links from a piece kept whole, decoded through a 16-entry LRU per view. A store whose index would pass memoTreeBytes keeps none and falls back to the bounded cache of walked trees.

On a clone of fossil-scm.org the trees take 11 MiB (the walked-tree cache held 50 MiB for two horizons), the memo's retained heap halves and peak in-use heap drops from 345-524 MiB to about 170 MiB. Tracked in #463. check-in: 1cb9e11a65 user: [email protected] tags: main, perf/memo-tree-encoding, trunk

Drop the stock-fossil caveat from the row, so it reports COVERED, and probe zit's reply to req-clusters under a horizon pragma (after a dense control). leaf check-in: e9eb2cabac user: [email protected] tags: conf/hz-4-1-1-zit-scope, main, trunk

fix(content): classify a fossil-written store's file versions from its tables check-in: d3574f0c74 user: [email protected] tags: main, trunk