A message encoder started its node array at 16 nodes of 184 bytes and
kept the array, with its unused capacity, until the message was
received. A port that queued many messages held about 3 KB of zeroed
memory per message: 200,000 queued numbers took about 590 MB, and the
page faults made postMessage cost about 1.3 µs. The node array now
starts at 4 nodes and is trimmed to the message's node count when
encoding ends.
scr_channel_post posted a wake event, and with it a pipe write and a
condition broadcast, to the receiving thread's mailbox for every
message. The owner's loop counts a port with queued messages as ready,
so only a message that finds the queue empty needs to wake it.
bench/channel-messages, added here, posts 200,000 messages (numbers and
small objects) on a MessageChannel before the port delivers any.
Resolve the emitter.ts import conflict by keeping both RESULT_DST_ID
(frame-stored result slots) and specializeCallbackCalls (#1206).
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Resolve the scr_resume_fiber conflict with stackless async coroutines
(#1204): the region the fiber carries is made current before either
resume path and restored after both. scr_async_spawn_stackless now
captures the spawning region like the fiber spawns, so stackless bodies
(every async body in 5013 and 5023 after the merge) keep allocating in
their region after an await and keep it alive while they exist.
5024-lifetime-region-await-forms pins regions carried by stackless and
fiber (for await) bodies that spawn and await each other.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
ThreadSlots<K, V> holds one value per key and thread, like a WeakMap that
each thread has its own copy of; under Node.js it is a WeakMap per name
and thread. Setting a value never writes the key, so values can be set on
published keys.
Classes used as keys carry a 32-bit slot word after their header words,
assigned on the first set for a key (with a compare-and-swap for a
published key) and never reused. Each family has one block per thread
that maps slot indices to values through pages of 1024 entries. get and
has are inline reads of the slot word, the page and the entry; set and
delete call scr_slots.c, which holds one reference to each value. A key
class's free paths release the key's values, and thread exit releases the
rest.
shift() moved every remaining element down one slot, making queue drains
quadratic (100k elements: 0.85 s; 1M: no result in 30 s). Dense arrays of
8-byte slots with their own allocation now remove front elements by
advancing data/present and lowering cap; the vacated slots stay in the
allocation as head room. A flag in `spare` marks it and its size is
implied by the layout (present == data + cap + head), so every reader,
including inline element access in emitted code, is unchanged. Growth
moves the elements back to the start of the allocation (in place only
when that leaves half the moved count free, else geometrically), a
drained array starts over at the front, unshift reuses head room, and an
array unshift already had to move once reserves head room for half its
length. scr_arr_outline drops head room before compiled storage swaps.
Booleans, inline slots, sparse arrays and static arrays keep the old
behavior.
Scaling probes: shift/BFS/splice(0,1)/deque drains and unshift runs go
from exponent ~2.0 to ~1.0 (shift 1e5 847 ms -> 1.6 ms); runtime bench
geomean 1.0045 (neutral).
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Frame storage for non-escaping records was limited to number, boolean and
inline-union fields. Records with string, array, record or class fields,
tuples, and same-shape spread updates (`{ ...state, count }`) were always
heap-allocated, even when every use only projected them.
Closed record and tuple shapes now qualify regardless of field types. The
frame owns the reference fields: they start empty in entry-addressed slots
and are registered before anything is stored, with the binding's lexical
scope for locals and with the statement frame for call-argument
temporaries, so an exception while the record is being built releases
exactly what was stored. Interned string literal fields need no owner.
A reassigned binding builds the new value apart, copies it over its slot
and then releases the replaced fields. Result-slot entries cover producers
returning such records, tuples and spreads of a binding, and store into
the zeroed caller storage without releasing an old value. A spread of a
binding is a projection for the lifetime analysis. Published shapes and
switch-case bindings of reference-owning shapes keep heap storage.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
An async function called inside LifetimeRegion.run now keeps its region
after every await: its fiber records the region that was current at spawn,
and the event loop makes that region current while it resumes the fiber.
A region is not freed (or attempted) while a fiber that carries it exists,
so a region released while its async work is pending keeps taking that
work's objects and is freed once the work ends. Before, objects created
after an await went to the default region, which is never freed, and kept
the request's region allocated for good, so per-request regions in async
servers grew without bound.
Freed region chunks now go to a per-thread cache (at most 8 MiB resident,
the first 256 KiB of each kept cleared, fresh pages past it, no huge-page
chunks) instead of being unmapped, so a region per request or per batch no
longer maps and faults in new memory every time.
Adds the requests.ts region benchmark (concurrent async handlers), corpus
5023 and its region-stats checks, and a chunk-reuse runtime unit check.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Every release of a LifetimeRegion, and every retry at region creation, ran
scr_collect_cycles(): full cycle-collector passes over the thread's heap, to
a fixpoint, before checking any region, in case dead cycles of ordinary
objects held counted references into it. Freeing a region ran them again
whenever the owned ordinary objects left counts behind after the region
released its fields. Next to a large heap of candidates (a type checker
beside per-file emit regions) those passes cost far more than the regions.
A retry now checks the due regions first. A region whose references are all
explained frees without a pass; only when one would be kept does the heap
get the full pass, after which every due region is judged as before. The
first check leaves a region it cannot free as it was, so the backoff, the
kept report and SCRIPTC_REGION_DEBUG see only the check after the pass. It
keeps what its walk found: a region whose counted references the pass did not
change is judged from that, without walking it again. A pass that freed a dead
cycle referring only to an owned object leaves the count unchanged; such a
region waits for its next attempt.
After a region releases its instances' fields, what can still hold counts
is the owned ordinary objects' cycles. Each has a member that lost a
reference in those releases and is buffered as a candidate, and the release
walk entered every cycle member. The cycle collector gains a pass limited to
a set of candidates (scr_cyc_collect_set): it takes the set's members out of
the buffers up to a given generation, reading only the buffers' pointers, so
the candidates it leaves are not touched, and it walks at full depth without
moving the schedule's baselines. A dead object such a pass reaches through a
candidate it did not take leaves its buffer before it is freed. Freeing a
region runs these passes over the walk's objects from the youngest buffer
out, and the whole heap only if counts remain.
SCRIPTC_REGION_STATS also prints, per thread at exit, how many full passes
over the heap regions needed.
Atomics operations on 8-, 16- and 32-bit integer arrays are sequentially
consistent atomic instructions on the element, and no longer take the
process-wide shared-memory lock. Other reads and writes of shared storage
are relaxed atomic accesses: element reads and writes access the element,
and copies, fills, conversions, searches and sorts read shared bytes into
a private copy and write back only the range they change, so concurrent
accesses to the same bytes are free of data races. Non-shared storage
keeps its plain memory accesses. Atomics.wait and Atomics.notify queue
waiters in buckets chosen by location, each with its own lock and
condition variable, so waiting threads no longer serialize other Atomics.
Atomics.store answers +0 for a value that truncates to -0, as Node does.
The shared storage runtime test also runs under ThreadSanitizer.
Every region creation, release and pressure retry walked every condemned
region again. A released region that something still refers to was
re-walked on each of them, two or three times per build in a watch loop,
and each walk visits every object of the region.
An attempt that keeps a region now records the references counted to it.
Retries at creation, release and region entry attempt a kept region again
only when that count has changed, or once the thread has allocated 8 MiB
(or the region's size, if larger) in regions since the attempt. That
volume doubles after each attempt that finds the count unchanged, up to
64 times. The volume covers references from ordinary objects the walk
reaches, which can go away without changing the count. The schedule is
per region, so a region that another region's release unblocks is
attempted at once, and the full cycle collection before an attempt runs
only when some region is due.
Adds the region-builds runtime benchmark and a region test for the
schedule.
publish() used to remove each published object from this thread's
cycle-collector candidate buffers after the walk, which loaded every
object's collector header a second time. On graphs larger than the
cache that second pass took about a third of the publish.
scr_pub_mark now takes a buffered object out of its buffer when it marks
it, while the header is in cache: the slot is cleared and its index
recorded. When the publish ends, scr_cyc_pub_fill closes the empty slots
with entries from the ends of the buffers. A refused publish puts each
taken object back in its slot first. After the walk, the log is read only
for dyn containers, the RC audit and LeakSanitizer.
The emitted walkers test null and immortal references (parent links,
values published before) before calling scr_pub_push, and the string
walker checks for ASCII 32 bytes at a time.
Adds the published-graphs runtime benchmark, a cycle collector test for
the take, restore and fill hooks, and corpus program 5702.
@scriptc/experimental exports InternTable<K, V>: a named table that every
thread of a scriptc program shares and that each thread has its own copy
of under Node.js. Keys are strings or numbers with Map equality; values are
published (@scriptc/threads) when stored, and the first stored value of a
key is kept. Members are get, has, size, getOrInsert and
getOrInsertComputed.
The runtime table (scr_itable.c) splits each table into 64 segments.
Lookups take no lock and do not write; inserts take a segment's spin lock
for a probe and a few stores, and callbacks run without a lock. Number
tables keep keys and values in the index; string tables keep entries in
segment-owned chunks behind tagged slots. Replaced indexes are kept.
The compiler lowers the class to a synthetic class with one f64 handle
field and five intrinsics, with interned helpers per member and type and
an in-place lowering of getOrInsertComputed that creates a function
expression callback only on a miss. Stored values go through the publish
intrinsic, so their types get the write guard. scriptc refuses names that
are not string literals, one name opened with different type arguments,
and key or value types a table cannot store.
scr_publish walks small graphs in inline buffers and reads
SCRIPTC_PUBLISH_TRACE once, instead of allocating and calling getenv on
every call.
A candidate release now also runs a pass once the live cycle-headered
count has grown by 4096 objects since the last pass. A dead graph is
usually reachable from one candidate (its root), so the candidate count
alone let a few hundred dead graphs pile up before a pass, which then
walked them after they had left the cache.
markGray records the objects it grays and counts the ones still
externally referenced after the trial decrements. When none is, every
gray object is garbage, so the pass whitens the recorded set and skips
scan. markGray also records each edge it skips into an older generation,
so a restricted pass pins those targets without tracing the white set a
second time.
Adds the cyclic-graphs runtime benchmark and corpus programs 5700 and
5701.
Number-key reads of a map without the direct index called
scr_map_entry_f64 for every lookup. The internal sc_map_entry_f64 helper
now calls sc_map_entry_f64_hashed for such maps instead: it hashes the
key as scr_map_find_f64 does (SameValueZero key word, scr_key_mix, the
absent-key filter), scans the entries of a small map or probes a compact
bucket table, and calls the runtime lookup only for a table wider than
the compact limit. It stays out of line so the direct-index path stays
small at every call site.
The runtime fallback is called as a read-only call, so both helpers only
read memory and LLVM merges lookups of one key when nothing is stored in
between, such as a has() followed by get().
The runtime benchmark suite gains number-maps: a node table indexed by
dense ids, scope tables keyed by sparse ids, and get/has/set mixes.
In worker-enabled executables a typed-array access tests whether the view
is shared. The test used to come before the index check, and the shared
path called scr_bytes_get_or_nan/scr_bytes_set with the index as a
double, then converted the element back to an integer. Both paths now
use the index the inline check produced: the shared test follows the
check (a view's length never changes), and the shared path calls new
runtime entries that take the index as a size_t
(scr_bytes_shared_get_int, scr_bytes_shared_get_f64,
scr_bytes_shared_set). Integer elements join as one 32-bit value and
convert to a number after the join, so compares and ToInt32/ToUint32
of the result stay integer operations in every element kind.
The amortized worker cancellation poll moves from the loop header to
the loop's back edge (the continue target). In the header it was a loop
exit ahead of the body, which kept LLVM from rotating the loop and left
loads such as the view's length inside it.
Adds the typed-array-scan and typed-array-scan-workers runtime
benchmarks: Uint8Array, Uint16Array, Int32Array and Float64Array scan
loops in an ordinary and a worker-enabled executable.
A record built from unchecked element reads can hold undefined in a field
the checker calls present. Such a record kept its widened layout only in
an inferred binding: an annotated parameter or return, or an unannotated
return, converted it to the declared layout with a checked narrow, which
throws a TypeError for a missing element where Node passes undefined
through.
Record values that flow between bindings and the parameters and results
of functions and methods whose every call is visible now form flow
classes. A class takes the widened layout, with the union of its members'
optional fields, when it is closed: each value entering it is a fresh
object literal or comes from a member, each use of a member reads or
writes its fields, passes it to another member or only inspects it, and
every member declares the same shape. Members then share one layout, so
no conversion runs at the boundary and the record keeps its identity.
A class that reaches other storage keeps the declared layout for every
member, including the inferred bindings and the record parameters the
analysis widened before. Converting there copied the object, so writes
through a parameter or a pushed record did not reach the caller's object;
such a literal now converts once where it is created.
log-lines writes 200k lines (scale 4) through the common console shapes:
a single template literal, string plus number arguments, several
primitive arguments, process.stdout.write chunks, and an occasional
console.error line. The runner captures stdout through a pipe, so the
workload measures immediate per-line writes into a pipe.
The suite only had single-process CPU workloads. Add the two largest
real-world categories:
- http-api (kind "server"): a node:http JSON API in the static subset
(routing, query parsing, seeded catalog, per-cart state, typed JSON
bodies, ETag/If-None-Match, auth and request-id headers), driven by
clients/http-load.mjs, a raw-socket keep-alive HTTP/1.1 load client
that is identical for every server. 64 connections, 2 client threads,
4,000 untimed warmup and 40,000 measured requests on loopback. The
per-connection request schedule is seeded and server state is
partitioned per connection, so the response digest is deterministic.
Correctness compares server stdout, server stderr (minus the PORT
line), exit status, and client stdout with Node byte-for-byte. The
timed sample is the measured-phase wall time; a second table reports
req/s, p50/p90/p99 latency, client CPU, and peak RSS.
- cli-config (process, launches: 20): a deploy-plan CLI that reads a
~110 KB JSON manifest, validates, interpolates env values, and orders
80 services into dependency waves. Each sample is the median of 20
launches, so startup dominates.
The runner stays backward compatible: process workloads behave as
before, the JSON report keeps its fields and adds kind, launches,
category, server, node_peak_rss_bytes, and geomean_vs_node_by_category,
and the summary prints per-category geomeans (cpu, startup, server).
Fourteen application-shaped workloads (JSON, regex, parsing and class
dispatch, sorting, rendering, collection pipelines, async fan-out,
Map/Set graphs, allocation, numeric kernels, exceptions, CSV, and the
two multi-module build benchmark apps on large inputs).
bench:runtime builds each workload with one or two checkouts, refuses to
time any executable whose stdout, stderr, or exit status differs from
Node, interleaves baseline and candidate launches, and reports medians
with bootstrap 95% confidence intervals, binary size, and peak RSS.
* Make native installs portable and smaller
- Support glibc 2.34 with portable compiler binaries and static LLVM helpers.
- Bundle the host runtime and discover optional cross-target packs from project dependencies.
- Add application build benchmarks covering latency, executable size, and memory.
* Keep bootstrap tools available in Sandbox validation
- Isolate Zig for native compiler bootstrap and glibc entropy contracts.
- Preserve the existing toolchain scope for cache and corpus tests.
* Fix portable compiler bootstrap linking
- Keep native support objects compatible with the destination host linker.
- Resolve installed targets using the host declared by the toolchain manifest.
Chris Tate