N1: a full alarm-state snapshot also sets the condition's Quality, so it now
supersedes an earlier quality-only write for the same id in the deferred
buffer; a quality arriving after the state is kept and replays after it.
N2 / M1: the replay is not inert on a node the apply KEPT - an SDK-applied
Acknowledge/Confirm/Shelve or an optimistic client Write in the window would
be rolled back (with spurious Part 9 events). The replay is now scoped to
nodes the apply created: variables the applier ensured during this apply
(AddressSpaceApplier.BeginRecordingEnsuredVariables) or every variable after a
full rebuild; conditions in the applied composition but not the previous one
(also on a rebuild, which carries a kept condition's state over). Option (b),
a sink that reports whether a live write landed, needs the Commons
DeferredAddressSpaceSink seam outside this lane (follow-up F7).
M2: the benchmark remark now matches its Category=Benchmark trait.
M3: TestHooks and the seam-carrying constructor are internal; PropsForTests
produces the actor through an IIndirectActorProducer.
M4: pinned replay-nothing-and-drop-the-buffer after a failed plan.
M5: PreRestart answers every queued rebuild requester (degraded).
Refs #732
Claude-Session: https://claude.ai/code/session_01Ub9hGmYLQvn9XETzw7CMsT
C1 (critical): B6 computes the plan off the pinned thread while B1 made writes
non-creating, so a value/status/alarm write for a node the in-flight plan adds
was skipped, and change-driven drivers never republish it (BadWaitingForInitialData
indefinitely; on a full rebuild every re-subscribe value landed on discarded
nodes). OpcUaPublishActor now applies writes immediately AND remembers the
latest per (realm, id) while a plan is in flight or queued (value+status
compose; alarm state/quality coalesce to the latest, which the node's delta
gate makes inert on an existing condition), replays it after each apply before
answering, and drops it once the pipeline is idle. Bounded (250k keys by
default; beyond it new keys are not held, logged once).
I2: the data-plane-authority parse runs in its own try inside the plan task; a
throw is logged and never degrades the address-space apply.
I3: the SDK's DeleteMonitoredItems releases an item's component-cache
reference on a Good delete; a tombstoned item's reference was already
released, so the delete took one from the re-created node's entry. Released
items are remembered and the orphan delete takes one back first. Event items
never held a reference (EventManager + SubscribeToEvents), so the three
event-item releases are gone.
I4: direct tests for the HistoryUpdate override's per-request updater check
and the HistoryReadEvents override's source guard (both reached by restoring
the bit after a reset - the B7 race window); fixed the false remark.
Minors: the MaterialiseAlarmCondition kind-swap tombstones the dropped
instance; a bytes-less rebuild arriving mid-plan queues behind it (replies in
order); a PlanReady/PlanFailed from a previous actor incarnation is ignored and
its requester answered degraded; the tie-cluster end bound of an uncapped read
fits against the backend ceiling (defence in depth - guarded by a sweep test);
the lock-time benchmark stays in the default run, headroom noted.
Refs #732
Claude-Session: https://claude.ai/code/session_01Ub9hGmYLQvn9XETzw7CMsT
Review 01 P1/P2/P3/P5 — work done under the manager-wide SDK Lock on the
pinned publish thread, where every Read/Browse/Publish waits.
- P1 RebuildAddressSpace detaches the shared root's top-level children
once instead of every leaf from its parent (NodeState.RemoveChild is a
linear scan + RemoveAt, ~k²/2 compares per k-child folder); root
notifiers are cleared as a list instead of one O(F) RemoveRootNotifier
each; ForgetPredefinedSubtree / TombstoneMonitoredSubtree are iterative
with one child buffer.
- P2 RemoveEquipmentSubtree walks a parent→children index maintained by
EnsureFolder/EnsureVariable/MaterialiseAlarmCondition (keyed by the
parent id the caller named) instead of prefix-scanning six maps per
removed equipment; a surviving condition's wiring into a removed folder
is found through the folder's own notifier list; descendants are not
detached from a folder that is itself being discarded.
- P3 LowerAllEventsMonitoring(condition) replaces the full O(C) reconcile
on RemoveAlarmConditionNode / RemoveEquipmentSubtree / the kind-swap.
- P5 AlarmNotifierWiring.Folders is a reference-identity HashSet and an
already-wired pair skips the SDK's linear AddNotifier dedup.
Benchmark (NodeManagerLockTimeBenchmarkTests, M-series Mac under load,
three runs each): rebuild of a 10k-tag folder 75–150 ms → 5–6 ms;
removing 200 equipment (250 signals each) from a 50k-node space
471–681 ms → 58–64 ms; all-events bookkeeping visits for 10 condition
removals over 50 conditions 900 → 10. The two timing legs assert < 1 s;
the P3 leg asserts the visit count (machine-independent).
Refs #732
Claude-Session: https://claude.ai/code/session_01Ub9hGmYLQvn9XETzw7CMsT
Joseph Doherty