shoney.arickathil
771180fd28
- Float full stack: literals (fraction/exponent; `0..10` still a range), f64
opcodes 34-41, @table column, WAL bit-exact replay, json fractions in and
shortest-round-trip out. IEEE-quiet — FDIV never traps where DIV does.
- Bytes: a wo_str with its own class id, so alloc/free/copy are shared but no
Text builtin accepts one; len/at/slice/eq/concat, base64 both ways, json
boundary as base64; TEXT_COPY preserves the kind.
- No implicit Int/Float mixing (WO-E201 in the typechecker, not the emitter,
which picks the opcode from one side and would misread the other).
- One IEEE deviation: float_cmp total order (NaN last, -0.0 == +0.0) for
indexes and order-by, keys canonicalized to match. `?Float` nil is a
reserved quiet NaN — the zero word is +0.0, WO_NIL_SCALAR's bits are -2.0.
- Renderer prefers fixed over exponential in 1e-6..1e21: pure shortest makes
a price of 900.0 read `9e+02`. One renderer for interp/json/float_to_text.
- Fixed en route: lexer double-counted the leading digit; is_scalar_shaped
took Float/Bytes as Int-shaped; Bytes ownership needed a shared heap-scalar
predicate or temps never dropped; order-by bit-compared negatives backwards.
- Iteration 17: `kind = "library"` (absent = program; bad value = WO-E109),
entry-less check mode retiring the `--emit` workaround, Go's `internal/` as
WO-E108 at the consumer's `use`. Driver-only; VM/.wob/GC untouched.
- Framework reorg: internal/{parse,serve}.wo; http/form.wo split out to keep
media_type/form_values public (parse.wo had grown public surface).
- Docs: link audit (97 -> 88 broken, conflict markers resolved, 2 duplicate
stories removed), 00-code-review verified 26/27, iterations re-sequenced.
- Also carries the pre-staged pub(read)/using/#if work from the index.
- Gates: corpus 103/0, test_wal 156/0, web-app 26/0, oop-accept ALL MET.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
110 lines
5.4 KiB
Markdown
110 lines
5.4 KiB
Markdown
# Iteration 8 — shard-actor runtime (the 8+11 concurrency arc, part 1)
|
||
|
||
> Format: fiberloom `product/story-iteration-template`. Part of
|
||
> [Story — one language, one runtime, one database, one binary](../00-story.md).
|
||
>
|
||
> **REFINED 2026-08-20** (developer decisions, no code): iterations 8 and
|
||
> 11 are **one arc** — the scheduler, fibers on it, then serving — because
|
||
> the database-ownership decision below makes a fiberless multi-shard
|
||
> server block a whole thread per cross-shard call. The arc's driving
|
||
> workload is **iteration 24 (chat: WebSocket pub/sub)**. The pre-existing
|
||
> plan (`docs/superpowers/plans/2026-08-01-shard-actor-vm-runtime.md`)
|
||
> predates inferred GC (7b), the unified surface, and the DB decision —
|
||
> it is a source of ideas, NOT the plan of record; the arc starts with a
|
||
> fresh brainstorm → spec → plan.
|
||
|
||
## Settled decisions (2026-08-20)
|
||
|
||
1. **The database is an actor.** The engine (`wo_db` + WAL) lives on one
|
||
owner shard; every query/write from another shard is a message send,
|
||
and results come back materialized (queries already copy rows out —
|
||
the model was built for this). Doctrine-pure: no lock, no shared
|
||
mutable state. Consequence, accepted deliberately: callers must PARK
|
||
while the reply travels, which is why 8 and 11 ship as one arc.
|
||
(Rejected: a coarse engine lock — bends the doctrine and caps write
|
||
scaling anyway; partitioned tables — the real scale answer, but it
|
||
waits for a measured need, not v1.)
|
||
2. **One concurrency surface: everything is an actor address.** `spawn`
|
||
returns an address whether the spawnee lands on this shard (a fiber)
|
||
or another (placement policy's call); `send` always moves ownership;
|
||
a same-heap send skips the ring and is cheap. The language never
|
||
shows a fiber-vs-actor split. (This dissolves iteration 11's
|
||
"handle vs address" open question.)
|
||
3. **Driving workload: chat** (iteration 24) — rooms, broadcast, N
|
||
concurrent WebSocket clients, one binary. The arc's acceptance is the
|
||
chat sample's, not only synthetic corpora.
|
||
4. **Order: 22 → the 8+11 arc → 23.** The io_uring write path waits for
|
||
the arc (its batch boundary is the shard tick) and for 22's baseline.
|
||
|
||
## Goals
|
||
|
||
- The runtime scales past one core the doctrine way: pinned
|
||
thread-per-core shards, each owning its own heap and event loop;
|
||
cross-shard communication is a message send that **moves ownership** —
|
||
shared mutable state never exists.
|
||
- The language grows `spawn`/`send` (the unified address surface);
|
||
garbage collection stays per-shard (7b's collector is already
|
||
per-shard by construction), so no global pause appears at any core
|
||
count.
|
||
- The database keeps its single-writer truth by BEING an actor on its
|
||
owner shard.
|
||
|
||
## Acceptance Criteria
|
||
|
||
- What to achieve?
|
||
- **Given** a program spawning actors across shards,
|
||
- **when** an owned object is sent to another shard,
|
||
- **then** the sender can no longer touch it (compile-time move), the
|
||
receiver owns it, and its eventual free routes back to its
|
||
allocation-home arena.
|
||
- What to achieve?
|
||
- **Given** debug builds with shard-ownership asserts,
|
||
- **when** the deterministic actor corpus runs under ASan and TSan,
|
||
- **then** zero races, zero leaks, and identical output across runs.
|
||
- What to achieve?
|
||
- **Given** a reference to a TRACED object (GC-ness is inferred since
|
||
7b — there is no `@gc` to write),
|
||
- **when** code attempts to send it cross-shard,
|
||
- **then** the compiler rejects it: aliased references cannot cross
|
||
heap boundaries, and the diagnostic names the inferred-traced class
|
||
and why it is traced. (This criterion originally said `@gc`;
|
||
restated 2026-08-20 in inference terms — same rule, current
|
||
language.)
|
||
- What to achieve?
|
||
- **Given** handlers on serving shards querying and writing through
|
||
the DB-owner shard,
|
||
- **when** the employee/web-app matrices run multi-shard,
|
||
- **then** every answer is byte-identical to the single-shard run and
|
||
the WAL's ack-after-durable contract is unchanged.
|
||
|
||
## Out Of Scope
|
||
|
||
- Cross-shard transactions (2PC) — the DB actor serializes writers, so
|
||
iteration 18's `transaction { }` is unaffected; distributing it is a
|
||
later story.
|
||
- Fiber details beyond the shared scheduler substrate — part 2
|
||
([iteration 11](11-fibers.md)) owns them.
|
||
- WebSocket framing — the framework's (iteration 24's) job.
|
||
|
||
## Info
|
||
|
||
- The C proving ground (`docs/plan/exploration/c-runtime/`, phases A–F:
|
||
epoll loops, eventfd mail) is the substrate this lifts into `wovm`.
|
||
(Path restated 2026-08-20; the old `runtime/wo-rt.c` reference was
|
||
stale — that tree was removed with the Rust runtime.)
|
||
- The VM's object header has carried a shard id since iteration 2 — no
|
||
relayout.
|
||
- **Gated by the benchmark:** landing the arc means re-running
|
||
[22](22-durability-throughput-scale.md) at the concurrency
|
||
scale it unlocks and recording the before/after delta; it is also
|
||
where [23](23-io-uring-commit.md) gets a thread to overlap
|
||
durability against.
|
||
|
||
## Proposed Solution
|
||
|
||
Fresh brainstorm → spec → plan for the WHOLE arc (8+11), staged: the
|
||
pinned-worker scheduler + shard-stamped heaps + MPSC mailboxes + the
|
||
unified spawn/send surface and the traced-send rejection; fibers on that
|
||
scheduler (part 2's document); the DB-actor migration; then iteration 24
|
||
proves it. The 2026-08-01 plan is reference material for the mailbox and
|
||
heap-stamping shapes only.
|