shoney.arickathil
d24c705860
- 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)
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> Format: `product/story-iteration-template`. Part of
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> [Story — one language, one runtime, one database, one binary](../00-story.md).
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>
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> **REFINED 2026-08-20** (developer decisions, no code): iterations 8 and
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> 11 are **one arc** — the scheduler, fibers on it, then serving — because
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> the database-ownership decision below makes a fiberless multi-shard
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> server block a whole thread per cross-shard call. The arc's driving
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> workload is **iteration 24 (chat: WebSocket pub/sub)**. The pre-existing
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> plan (`docs/superpowers/plans/2026-08-01-shard-actor-vm-runtime.md`)
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> predates inferred GC (7b), the unified surface, and the DB decision —
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> it is a source of ideas, NOT the plan of record; the arc starts with a
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> fresh brainstorm → spec → plan.
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## Settled decisions (2026-08-20)
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1. **The database is an actor.** The engine (`wo_db` + WAL) lives on one
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owner shard; every query/write from another shard is a message send,
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and results come back materialized (queries already copy rows out —
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the model was built for this). Doctrine-pure: no lock, no shared
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mutable state. Consequence, accepted deliberately: callers must PARK
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while the reply travels, which is why 8 and 11 ship as one arc.
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(Rejected: a coarse engine lock — bends the doctrine and caps write
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scaling anyway; partitioned tables — the real scale answer, but it
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waits for a measured need, not v1.)
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2. **One concurrency surface: everything is an actor address.** `spawn`
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returns an address whether the spawnee lands on this shard (a fiber)
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or another (placement policy's call); `send` always moves ownership;
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a same-heap send skips the ring and is cheap. The language never
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shows a fiber-vs-actor split. (This dissolves iteration 11's
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"handle vs address" open question.)
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3. **Driving workload: chat** (iteration 24) — rooms, broadcast, N
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concurrent WebSocket clients, one binary. The arc's acceptance is the
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chat sample's, not only synthetic corpora.
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4. **Order: 22 → the 8+11 arc → 23.** The io_uring write path waits for
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the arc (its batch boundary is the shard tick) and for 22's baseline.
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## Goals
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- The runtime scales past one core the doctrine way: pinned
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thread-per-core shards, each owning its own heap and event loop;
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cross-shard communication is a message send that **moves ownership** —
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shared mutable state never exists.
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- The language grows `spawn`/`send` (the unified address surface);
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garbage collection stays per-shard (7b's collector is already
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per-shard by construction), so no global pause appears at any core
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count.
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- The database keeps its single-writer truth by BEING an actor on its
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owner shard.
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## Acceptance Criteria
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- What to achieve?
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- **Given** a program spawning actors across shards,
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- **when** an owned object is sent to another shard,
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- **then** the sender can no longer touch it (compile-time move), the
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receiver owns it, and its eventual free routes back to its
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allocation-home arena.
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- What to achieve?
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- **Given** debug builds with shard-ownership asserts,
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- **when** the deterministic actor corpus runs under ASan and TSan,
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- **then** zero races, zero leaks, and identical output across runs.
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- What to achieve?
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- **Given** a reference to a TRACED object (GC-ness is inferred since
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7b — there is no `@gc` to write),
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- **when** code attempts to send it cross-shard,
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- **then** the compiler rejects it: aliased references cannot cross
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heap boundaries, and the diagnostic names the inferred-traced class
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and why it is traced. (This criterion originally said `@gc`;
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restated 2026-08-20 in inference terms — same rule, current
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language.)
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- What to achieve?
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- **Given** handlers on serving shards querying and writing through
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the DB-owner shard,
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- **when** the employee/web-app matrices run multi-shard,
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- **then** every answer is byte-identical to the single-shard run and
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the WAL's ack-after-durable contract is unchanged.
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## Out Of Scope
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- Cross-shard transactions (2PC) — the DB actor serializes writers, so
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iteration 18's `transaction { }` is unaffected; distributing it is a
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later story.
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- Fiber details beyond the shared scheduler substrate — part 2
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([iteration 11](11-fibers.md)) owns them.
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- WebSocket framing — the framework's (iteration 24's) job.
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## Info
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- The C proving ground (`docs/plan/exploration/c-runtime/`, phases A–F:
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epoll loops, eventfd mail) is the substrate this lifts into `wovm`.
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(Path restated 2026-08-20; the old `runtime/wo-rt.c` reference was
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stale — that tree was removed with the Rust runtime.)
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- The VM's object header has carried a shard id since iteration 2 — no
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relayout.
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- **Gated by the benchmark:** landing the arc means re-running
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[22](22-durability-throughput-scale.md) at the concurrency
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scale it unlocks and recording the before/after delta; it is also
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where [23](23-io-uring-commit.md) gets a thread to overlap
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durability against.
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## Proposed Solution
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Fresh brainstorm → spec → plan for the WHOLE arc (8+11), staged: the
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pinned-worker scheduler + shard-stamped heaps + MPSC mailboxes + the
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unified spawn/send surface and the traced-send rejection; fibers on that
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scheduler (part 2's document); the DB-actor migration; then iteration 24
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proves it. The 2026-08-01 plan is reference material for the mailbox and
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heap-stamping shapes only.
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