shoney.arickathil
0b618ace19
databasev2 4 part A, task 6. Mostly documentation, plus one real fix the
full battery caught.
THE FIX. The drain held EVERY DB reply until the barrier — including
reads, which stage nothing and have no stake in durability. That parked
readers behind an fsync for no reason: durable.sN.mixread.p99 rose from
~1043us to 4057us. Only a statement that actually staged a record now has
its reply held. Caught by the gate, not by review.
THE TRADE, recorded rather than smoothed over. What remains is inherent: a
barrier blocks the owner shard LONGER (more records per fsync) though LESS
OFTEN, so anything queued behind one waits. Three full runs of the same
build gave durable.sN.mixread.p99 of 1043 / 2318 / 4147us and wmix.p99 of
8758 / 20000us — a 2-4x spread with the box near idle. So part A buys ~3x
write throughput at the cost of a longer, noisier tail on the owner shard,
and that is the strongest argument for part B (submit and keep serving).
- durable.sN.*.p99us tolerance widened to 100% WITH the reason in the
code: a 2-4x-variable tail gated at 50% gates the disk, not the engine.
The floor is the real guard and is not slack — mixread's (4172us) came
within 25us of tripping on the worst run. Baseline refreshed; a fresh
full run then passed 106 checks 0 failures
EXIT STATUS MOVED 3 -> 74 (sysexits EX_IOERR). 3 and 4 are already used by
SAMPLES for their own meanings — db-bench's own `verify` exits 3 on a
checksum mismatch, and it is the gate that exercises durability, so a
durability abort exiting 3 would have been indistinguishable from the
mismatch it should help diagnose. The low range belongs to programs.
Docs:
- story: progress, the payoff measured two ways, the cost side, criteria
split met/outstanding, and a "part B — its premise changed" section:
it was justified by "close the 66x gap", but that gap is two problems
and only the concurrent one was a batching problem
- board: standup entry in the six-question shape; both databasev2 4 rows
rewritten. They had said "close the 66x gap" — recorded as MIS-STATED
rather than quietly renumbered
- 00-wob-format.md and 04-db-binding.md: the normative failure contract
("a failed WAL commit traps WO_T_IO after un-applying the row") was
false; corrected, along with the tick-scoped group commit that never
happened
- database/src/CODE-LOGIC.md: where the barrier runs and why there, why
replies are held, why the inline path is asymmetric, the one failure
rule, and how to measure it
- db-bench README: the wmix mode, the env knobs, and the tmpfs warning
Battery: wovm-test 36 suites 0 fail, woc-test, oop-e2e 119/0,
db-bench 106/0, linkcheck clean.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
|
||
|---|---|---|
| .. | ||
| 00-wob-format.md | ||
| 01-error-catalog.md | ||
| 02-corpus.md | ||
| 03-concurrency-coroutines.md | ||
| 04-db-binding.md | ||
| 08-builtin-surface.md | ||
| README.md | ||
docs/plan/oop-vm/ — OOP + systems track contracts
The normative contract documents both stacks cite. Landed by their named plan tasks:
| doc | contract | plan |
|---|---|---|
00-wob-format.md |
.wob bytecode format (compiler↔VM) |
1 |
01-error-catalog.md |
every WO-E### code |
2, grows 3/8 |
02-corpus.md |
how to add conformance fixtures | 3 |
03-concurrency-coroutines.md |
stackless fibers, park/resume protocols, reduction budget, the no-async rule |
arc (was plan 4's slot; that plan ✖ discarded 2026-08-21) |
04-db-binding.md |
row format, WAL records, query subset | 5 |
05-http-service.md |
route section, trap→HTTP table, JSON subset | 6 |
06-ui-live.md |
delta frames, subscribe protocol, wo:live | 7 |
07-systems-stdlib.md |
per-function nil-vs-trap contracts | 9 |
08-builtin-surface.md |
builtin source names, container/call/entry rules the emitter enforces | 3 |
Specs and plans: docs/superpowers/{specs,plans}/. Repo map: docs/08-project-structure.md.