Tree snapshot of d9c62a8 (2026-08-18). The 20 source commits between
16ef583 (c9) and d9c62a8 were never pushed and the clone that held them
was lost; this commit carries their combined tree verbatim so the build
history stays auditable from the c1–c9 commits below it. Original
hashes as recorded in the session handoff:
c10 f03e94d pid targeting + auto-serialization (RemotePid, D14 name
on the wire); Phase 3 gate
c11 7ef4bad DownReason::Disconnected, wire tag 5
c12 d124162 remote monitors (Monitor/Demonitor/Down frames)
c13 9de967b connection-loss synthesis (A+B: Monitors::teardown +
unread-command Disconnected); Phase 4 gate
c14 7e822b7 eager pg eviction (reaper actor, ReaperInboxes)
dbe1a22 InboundVerdict::label(), trace::Event::ClusterInbound
31a9877 tests/channel.rs monitor-churn target gated on `go`
653559e Discovery::Withdrawn{name, addr}
c15 b41d76e distributed pg: Sync on NodeUp, Join/Leave broadcast,
NodeDown sweep, members_all; PgMsg wire type
c16 fafa881 pick_any / dispatch_any; Phase 5 complete
Phase 6 Tier A:
195c73e p4 NodeEvent::NodeDown(NodeInfo)
48fd766 p1 connector Candidate{name, addr, state}
ce8cf99 p2+p7 conn.rs select arms as Vec<Arm>; Outbound::Drained
bf24988 p6 RemotePid::from_local -> Option
9ae0380 p3 PeerStanding{Free, Claimed, Dialing}
c7d62a1 p11 cluster::Timing knobs, threaded by value
46f171d p11 cluster_disconnect un-ignored on SMARM_FAST_TIMING
Phase 6 Tier B:
391a9ae p5 cluster::RemoteDownReason{Local, Disconnected};
DownReason::Disconnected removed from core
7ddd908 p9 pg ctl channel unconditional, one cfg seam at spawn
d9c62a8 PeerNameMismatch parks the candidate; ClusterDial trace
Verified at d9c62a8: default 361/0, cluster 448/0, clippy --lib on
default / cluster / cluster+smarm-trace, fmt, 10x flake on
cluster_dial_mismatch, 5x on cluster_pg.
The per-recv deadline the roadmap deferred, built exactly the way
Mutex::lock_timeout already works: register the wait with a per-wait
seq, arm a timer::Reason::WaitTimeout with the channel inner (now a
TimerTarget) as the target, park. On expiry on_timeout cancels the wait
only if that same seq is still parked; satisfied or abandoned waits
leave a stale heap entry that no-ops on seq mismatch, per the
no-cancellation convention in timer.rs.
Race resolution is message-first: a send that lands by the time the
woken receiver runs is delivered even if the deadline had also passed.
Closure is reported as RecvTimeoutError::Disconnected, keeping timeout
and server/sender death distinguishable for callers (gen_server call
timeout builds on exactly this distinction next).
The timer is armed outside the channel critical section (the timers
lock must never nest under a Channel-class lock); the unpark race this
opens is absorbed by the RunningNotified protocol.
Tests: immediate delivery, actual timeout (with elapsed check), prompt
wake on send, Disconnected on close, zero-duration poll, post-timeout
seq isolation (stale entry must not cancel later waits), and a
4-scheduler mixed-outcome run (12 fed / 12 timed out).
Phase 2 surfaced the hole this closes: channel guards were held with
preemption enabled, so a timeslice switch inside a channel critical
section could release the pthread mutex from a different OS thread (UB).
RawMutex disables preemption for the guard span and is
cross-thread-release sound by construction; poison goes away with it.
The strict single-class leaf rule cannot survive the migration: finalize
clones the supervisor/trap senders and monitor() clones the Down sender,
all under a cold lock, and those senders live in the slot - the nesting
is structural. The leaf check is therefore generalized to two classes:
Leaf (cold locks, free list, stack pool) and Channel. Order is
Leaf -> Channel, at most one of each; both directions of violation are
debug-asserted at the acquisition site. Channel critical sections call
only the lock-free unpark protocol, so the order is acyclic.
Tests: class-ordering unit tests in raw_mutex (allowed nesting + all
three rejected shapes), plus a multi-scheduler integration test driving
channels through monitor churn and actor death so any ordering
regression trips the debug assert instead of deadlocking.
Hand-rolled context switching on mmap'd stacks with guard pages,
allocator-driven RDTSC preemption, unbounded MPSC channels, supervision
via per-slot Signal mailboxes, root supervisor as sentinel PID.
Lib + tests + benches clean check/clippy. All 29 tests pass.
Bench: smarm 3.4% over serial baseline, within 160us of tokio
current-thread on prime-counting fan-out.