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Parents and children of check-in [f1ac625093]

2026-08-10
19:31
Fold managed/undo/bisect into the .zit-checkout container v2 (consolidation Task 6)

Sectioned container (ZITCKOT, tagged table, whole-file CRC); payloads are the existing formats unchanged. Byte-1 dispatch migrates legacy checkouts on first write; siblings dead once a container exists. Undo/redo restore and the commit/merge record+membership writes each collapse to one atomic splice. DST gains a legacy-seeded migration sweep (full-legacy or full-container at every crash cut). Registry: the three names move to the legacy tier. Perf on pkgsrc: adjacent update 6.50s (was 6.8), no-op 5.14s (was 7.69); migration of a 66k-file checkout invisible inside one update. check-in: efa29d234f user: dmestas tags: sub-manifest

17:25
control files: registry, provenance opt-in, one scratch prefix, advisory dir

Tasks 1-5 of the control-file consolidation plan. The checkout root goes from twelve zit-owned names to six live ones; the authoritative-tier container (task 6) and legacy removal (task 7) are deliberately not in this change.

Registry: control_paths now carries every reserved root name with its tier -- authoritative, advisory, scratch, legacy -- and is the single authority the case table, the extras exclusions and the ignore-glob coverage pin all derive from or test against. A name added without its glob line or case coverage is a test failure, proven by mutation. The pin caught two live gaps on arrival: a crashed update's transaction directory had no ignore-glob line, and a crashed import's staging directory was never reserved at all.

import-git --provenance: the per-object map and the source ref manifest are now instrumentation, published only on request. The default destination is the repository and its checkout record -- fossil's own shape. Both files are still written and verified in staging every run; without the flag they leave with the raw generation, and the staging manifest check enforces whichever set was chosen.

Scratch: one prefix. .zit-tmp-txn- (update transactions), .zit-tmp-import- (import staging), .zit-tmp-pack (pack scratch; name only, the truncate-reuse and rewrite-exclusion lock protocol are untouched). One registry prefix row and one glob line cover the tier including names that do not exist yet.

Advisory: .zit-cache is a directory -- repo (derived-state cache) and vstat (materialization plan), with the tree-checkpoint's member reserved. A legacy cache FILE is served through a read fallback and migrated by the first write via rename through a scratch name: the derivation survives with no bytes copied and no re-derive. Verified on a 66k-file pkgsrc checkout: identical SHA-256 across migration of a 35.8MB cache, fallback reads at parity, no-op update 7.69s vs 7.74s.

Legacy spellings of every renamed or relocated name stay reserved and ignore-globbed until the removal release. check-in: f1ac625093 user: dmestas tags: sub-manifest

13:41
update: cost tracks the diff, not the width

Three fixes, each found by measuring the previous one's residue.

markUnchanged: a path byte-identical between baseline and target -- same digest, same mode, with requireClean having already proven the on-disk file matches -- is skipped by every mutation phase: staging both directions, the undo journal, deletion and rewrite. An update used to delete and rewrite the entire tree regardless of how little changed.

.zit-vstat: the stat sidecar written at materialization is now the BASELINE PLAN -- version-bound, CRC'd, carrying mode and plan order -- so requireClean rebuilds the baseline with zero tree flattens when it describes the current check-in, and proves most files clean by inode/size/mtime instead of reconstructing their content out of the log. Advisory throughout: any mismatch, staleness or corruption falls back to the flatten and the content compare, which stay authoritative.

ManagedSet.fromSortedPaths: building the 66k-entry managed set through insert was quadratic -- an O(n) sorted-position memmove plus the LIVE sortedUnique assert per call -- and measured at 23.9 SECONDS of a pkgsrc update, larger than every real phase combined. The plan's own order is already sorted and unique, so the set is now built in one pass, order enforced per adjacent pair, invariant asserted once.

Measured, same store and targets as #52's gate: sqlite (2.2k files): 117.8s flat -> 0.6s adjacent / 1.2s distant pkgsrc (66k files): 42.2s flat -> 6.8s adjacent / 8.9s distant pkgsrc user CPU: ~25s -> 1.3s Residue is stat I/O (two ~66k-file sweeps), not computation.

The lockstep flatten prune #52 proposed was never built: the flatten measured 178ms at 66k files once the real costs fell.

Tests: dirty AND delete of a skipped-diff file both refuse with the tree untouched; sidecar intact/absent/rebound-to-wrong-check-in all produce identical trees; an unchanged file provably keeps its inode; an updated tree equals a from-scratch materialization. Closes #52. check-in: 8797f53546 user: dmestas tags: sub-manifest