Timeline

ReleaseSafe asserts made the clone answer O(store), and serve's 5s deadline raced read + answer + write as one unit -- so a slow answer was cancelled mid-flight and the dead pread surfaced as error.Storage.

Asserts gone (zit verify covers them); the deadline now races read and write separately. Not scale-dependent -- machine speed vs a wall clock.

Stalled peer still cut at 5.0s. test/gate/e2e/dst green. check-in: 94bebf57f1 user: dmestas tags: trunk

The 5s per-connection deadline raced read + answer + write as one unit, so a slow answer was indistinguishable from a stalled peer -- and cancelling mid-answer surfaced as error.Storage, telling the peer the repository was damaged. Issue #22.

Read and write are raced separately, each with the full deadline; the answer runs unraced since it is bounded by the store, not the peer.

Verified: a peer that sends one body byte and stalls is still cut at 5.0s; pikchr reclone passes. test 2327/2327, gate, e2e 671/671, dst 6x1000, fuzz serve_request_garbage. closed check-in: 73bdc2fef1 user: dmestas tags: issue22-diagnostics

Under runtime_safety (ReleaseSafe -- the shipped build) emitCloneReply reconstructed every served artifact and its delta basis just to assert a declared size. That pushed a clone round past serve's 5s per-connection deadline, which cancels mid-answer; the in-flight pread then failed and the peer got HTTP 500 on a healthy store. Issue #22.

zit verify checks the same properties on demand, which is where O(store) verification belongs.

Also names the failure server-side: serve collapses every AnswerError into a bare 500, so serveAnswer now logs which one.

Reclone verified green: wapp 1038, althttpd 1695, pikchr 2842, libfossil 17218 (18 rounds). test 2327/2327, gate, e2e 671/671, dst 6x1000. check-in: 879b867bb1 user: dmestas tags: issue22-diagnostics

"the peer answered with an unexpected HTTP status" sends an investigation nowhere. 500 (the server could not build a reply), 413 (the request exceeded the body ceiling), 400 (a malformed container) and 417 (a rejected Expect: 100-continue) are four different bugs, and the message distinguished none of them. Issue #22 has been open on exactly that sentence.

transport.zig discarded the code at the status check because Zig errors carry no payload and the closed error set is deliberate. Rather than widen TransportError with a variant per status, the status is left on the Transport as last_status for the caller to read after the error, and syncRunFail names it: "the peer answered HTTP 500 (Internal Server Error)".

Immediately useful: re-running the issue #22 gate against the fossil corpus with this build turns its failure_reason from the old sentence into HTTP 500, which -- together with the reply-size arithmetic -- narrows the cause to OutOfMemory or ServerStorage and eliminates every 4xx path. The issue's own hypothesis, a per-round shun-snapshot readiness problem, is not among the candidates: that arm is documented unreachable and the code agrees.

Also corrects three comments Slice 2 falsified, all on the same read path:

logstore's open no longer CRC-verifies payloads, so the serve snapshot's contentImpl/wireImpl read faults are no longer "post-scan EIO or bitrot after a verified scan" -- ordinary stored corruption now reaches serve there, on the read. That is a better shape (one bad frame fails the round that touches it rather than making the server refuse to serve at all) but it makes that arm live traffic, and anything reasoning about how often it fires must start from that.

runPack and runShun both claimed their read-only open was an "integrity pre-flight" that aborted a corrupt source before a byte was written. It no longer verifies payloads. The guarantee still holds -- packLog pulls every artifact through srcContent, which propagates error.Corrupt rather than skipping the frame, and readFrameAt CRC-checks every read, so a rotted payload still aborts with the temp deleted and .zit untouched -- but it is now collected during the copy loop instead of at open. Both verbs RENAME OVER the original, so runPack's comment now states the consequence plainly: if srcContent is ever changed to answer null on a corrupt read, the rewrite would silently omit the damaged artifact and then delete the only copy of it.

Verified: fmt clean, test 2327/2327, gate, e2e 671/671. The new message checked against a stub server answering 500. check-in: b4637e26df user: dmestas tags: issue22-diagnostics

openReadOnly is what every CLI verb opens through, and until now it still checksummed every payload byte on every invocation -- so nothing users ran had gotten faster. It scans header-only now:

10k frames 42 MB 42.2ms -> 10.3ms 10k frames 410 MB 298.0ms -> 12.3ms 100k frames 416 MB 511.9ms -> 115.4ms 100 frames 419 MB 321.4ms -> 0.10ms

Open cost is a function of frame count rather than repository size. On a store of a few large artifacts it is effectively free.

This completes the sequence: vendor a faster crc, measure the path production actually takes, scan header-only on the append path, ship the fsck verb, then delete the eager check. Each step was gated on the one before it, and the deletion was deliberately last because it is the only one that gives something up.

What is given up: opening a repository no longer detects payload corruption. It surfaces on the read instead -- readFrameAt crc-checks every frame unconditionally now -- or on demand through "zit verify". That is the split git draws between ordinary operation and fsck, and it was signed off knowing the tradeoff. A damaged store also stays usable for everything that does not touch the damaged bytes, which the old eager check made impossible.

Slices 0 and 4 are closed too: the 4 KiB chunk widening landed inside verify, the only place that loop still runs, and the sidecar index is dead on its own gate -- the 100k-frame shape was to justify it by exceeding 150ms and came in at 119ms. mmap is dead alongside it, separately, because a mapping would keep shunned bytes resident and readable until every mapping dropped, which defeats reclamation rather than merely slowing it. Neither rejection is recorded at the logstore extension comment yet; that is the one piece of follow-up this leaves behind.

Verified on the merged tree: fmt clean, test 2327/2327, gate 19/19. On the branch tip, additionally e2e 671/671 and dst 6 seeds x 1000 steps. check-in: 6d9172d488 user: dmestas tags: trunk