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
Review 01 L2. The SDK keys its fan-out lists by NodeId and its component
cache hands back the CACHED NodeState for a NodeId it already holds, so a
rebuild or a surgical remove+re-add left a NEW item on the same NodeId —
from any session — bound to the DEAD node: created Good, fed its stale
initial value, never again, until every session had deleted its items.
Every removal path (RebuildAddressSpace, RemoveVariableNode,
RemoveAlarmConditionNode incl. the condition's instance-scoped children,
RemoveEquipmentSubtree) now queues BadNodeIdUnknown to the node's data
items, drops the MonitoredNodes entry, releases each item's component
cache reference and forgets the _liveItems/_eventItems entries. Items
the ACL pass stood down (on no fan-out list) are swept by NodeId. A later
client delete of an orphaned item is completed by the DeleteMonitoredItem
override / the SubscribeToEvents unsubscribe arm instead of answering
BadMonitoredItemIdInvalid or NRE-ing in MonitoredNode2.Remove. The
revalidation restore re-resolves the node by NodeId and no longer
re-attaches to Handle.Node blindly. Timestamps now come from the injected
Clock (UtcNow).
Tests: StaleMonitoredNodeWireTests (real SDK, three legs: rebuild,
surgical remove+re-add, second session; each keeps the old item alive,
proves the new item receives a value written after its creation, the old
one gets BadNodeIdUnknown, and its delete succeeds — all three fail with
the tombstone neutered), NodeManagerStaleMonitoredNodeTests (stood-down
item swept on surgical remove and rebuild; sibling removal leaves it
restorable).
Refs #732
Claude-Session: https://claude.ai/code/session_01Ub9hGmYLQvn9XETzw7CMsT
Review 01 L1/L4/H2. WriteValue/WriteValues are non-creating (an unknown
id is skipped, counted and Debug-logged, as WriteStatuses always was), so
a driver publish racing a surgical remove can no longer resurrect the id
as a flat BaseDataType phantom under the shared root — nor hand a later
re-add of the same tag the phantom's parent/DataType/writability through
EnsureVariable's early return. WriteAlarmCondition for an unmaterialised
id is a logged no-op instead of minting the legacy bool[2] placeholder
(AddPredefinedNode is AddOrUpdate, so it replaced the SDK lookup entry of
any folder sharing the id). The applier no longer writes a condition
state against every removed equipment id (a folder, never a condition).
EnsureFolder/EnsureVariable/MaterialiseAlarmCondition refuse an id already
held by another node kind in the same realm. CreateVariable is deleted.
Tests: NodeManagerPhantomNodeTests (publish racing a remove leaves no
node; the re-add gets the authored shape and is live; unknown alarm id
is a no-op; the guard in all three directions, realm-qualified); the
sink / batch-write / write-statuses tests now declare their variables.
Refs #732
Claude-Session: https://claude.ai/code/session_01Ub9hGmYLQvn9XETzw7CMsT
- RunWriteAsync wraps the invoker call in WaitAsync(writeTimeout) (Props,
default 10 s = 2x the 5 s write cap): a token-ignoring hung write now
answers BadTimeout, releases its slot and tag, and its orphan outcome
is observed and discarded - later writes to that tag reach the device.
- WriteCompleted carries the launching incarnation (from the process-wide
generation source); a late completion from a previous incarnation after
a supervision restart is ignored instead of freeing the new
incarnation's slot/tag.
- Test: a hung token-ignoring tag-a write is abandoned and a later tag-a
write reaches the device while the abandoned one is still inside it.
Refs #731
Claude-Session: https://claude.ai/code/session_01Ub9hGmYLQvn9XETzw7CMsT
- GatewayHistorianDataSource.ReadRawWindowAsync keeps the cap + 1 probe budget
(budgetCap) separate from the client's cap: a strict-ceiling or crowding
refusal now reports Limit = the server cap that applied and advises setting
NumValuesPerNode at or below it (it said "lower NumValuesPerNode" with
Limit = cap + 1 to a client that sent 0).
- Fuzz: the oracle-source over-cap assertion was vacuous (cap 0 never counts);
it now checks no reverse window reached the forward-only shape. Class docs
name the post-floor cap set (3 ... 1000) and distinguish NumValuesPerNode
1 / 2 from the smallest server cap.
- HistoryPaging.IsFullPage doc says it judges the REQUEST cap (page + ties +
lookahead), which is finite under any limit; AdvertiseMaxReturnDataValues
swallows any exception (returns false for the caller to log), as its doc
promised.
Refs #736
Claude-Session: https://claude.ai/code/session_01Ub9hGmYLQvn9XETzw7CMsT
- Writes: a second write to a tag already inside the driver waits in the
queue behind it (_tagsInFlight) while other tags still run under the
cap of 4; queued writes are stamped and failed BadTimeout at dequeue
once older than the 8 s host Ask budget (Props queuedWriteBudget)
instead of being written late.
- Initialise attempts are bounded pessimistically (initializeTimeout,
default 30 s = 2x Tier C) on top of the invoker's token-only timeout:
an overrun is logged as abandoned, reported InitializeFailed so the
retry loop continues, and its late result is dropped by generation.
Generations come from a process-wide Interlocked counter so a prior
incarnation's late result cannot collide (F6).
- PostStop shares one shutdownTimeout budget across shutdown + dispose.
- TelemetryDialSupervisor cancels the establishment deadline on
StreamStopped; FleetDiagnosticsClient builds the ActorSelection inside
the try (a malformed node degrades to "unavailable"); the diagnostics
page labels the column "Last health publish".
- Tests: same-tag serialisation with a distinct-tag positive control;
stale queued write BadTimeout; token-ignoring hung init -> later
attempt connects; stopwatch assertion demoted to a ceiling.
Refs #731
Claude-Session: https://claude.ai/code/session_01Ub9hGmYLQvn9XETzw7CMsT
- NodeManagerHistoryReadRawCapFuzzTests: 10k seeds (env OTOPCUA_PAGING_FUZZ_ITERATIONS)
through a real SDK node manager against wire-faithful fakes of SqlServer / QuestDB /
Gateway that enforce the backend half of the cap; random series with ties, random
windows (empty, on/past a tie, between samples, forward/reverse/end-only, bounds),
N in {0,1,2,small,huge}, cap in {off,3..1000}, tie budget {3,8,65536}. Pages must
concatenate to the cap-off one-shot answer (checked against the series), terminate
within values + 2 (+ one empty step per oversized boundary cluster), never exceed
the cap, never ask the backend for 0 / over-cap; refusals only past the budget.
- HistoryPaging.AdvertiseMaxReturnDataValues writes HistoryServerCapabilities/
MaxReturnDataValues (i=11273), read back through the SDK master node manager.
- MinMaxRawValuesPerRead raised to 3: at 2 a resumed page has no room (value + its
boundary tie + lookahead) and every value cost an empty page + CP (seed 15).
- RawPageLimit rows pin the default-cap arithmetic (9 999 first page, 9 998 resumed).
Fuzz findings recorded as follow-ups: a bounded read whose data fits one page
returns cap + 1 (end bound fitted against N, not the cap; node manager, F2);
the Gateway walk-back's cost on a sparse series under a tiny tie budget is
pre-existing (seed 320: 82 reads uncapped, 93 capped).
Refs #736
Claude-Session: https://claude.ai/code/session_01Ub9hGmYLQvn9XETzw7CMsT
DriverInstanceDiagnostics.Name carries the string driver-instance id
(what /hosts, telemetry and the artifact key on) and DriverInstanceId
the DB row Guid; the wire record has no slot for the authored display
name. The write-cap test asserts entry order per slot pair instead of
completion order of two concurrent writes.
Refs #731
Claude-Session: https://claude.ai/code/session_01Ub9hGmYLQvn9XETzw7CMsT
DriverHostActor wraps the health publisher it hands its children in a
ChildHealthLedger (last snapshot per driver id, forwarded to the real
publisher), so GetDiagnostics now answers with each child's row id,
authored name, last-published state, device counts (host statuses when
the driver probes hosts, else one device) and last-change time — instead
of Guid.Empty / "Spawned" / 0 / now. Entries are forgotten on StopChild
and operator Restart.
IFleetDiagnosticsClient gains its first consumer: the new
/fleet/diagnostics page (node selector + ?node= query, revision,
running-from-cache notice, per-driver table). FleetDiagnosticsClient
logs the degrade-to-empty path at Warning.
Review ref: 02/U1.
Refs #731
Claude-Session: https://claude.ai/code/session_01Ub9hGmYLQvn9XETzw7CMsT
CallTimeoutSeconds was bound, defaulted and documented but consumed
nowhere. TelemetryDialSupervisor now arms a per-generation deadline on
every dial: a dial that has delivered no event by the deadline is
cancelled and treated as a transport failure (reconnect with a failure
streak). A live node replays its snapshots on subscribe, so this bites
only a dial that never connects (a black-holed host, where the socket
connect has no timeout). An established stream is deliberately not
bounded — the wire has no heartbeat, keepalive pings own its liveness.
Review ref: 02/U2.
Refs #731
Claude-Session: https://claude.ai/code/session_01Ub9hGmYLQvn9XETzw7CMsT
- DriverHostActor.StopChild removes the driver's _lastReprovisionUtc stamp
(and its deferred-reprovision timer): the map grew per removed id and a
re-added driver inherited a backoff it never earned (02/L2).
- Stale now registers explicit drops for AttributeValueBatchPublished,
AttributeAlarmPublished, ArtifactForApply and ApplyWedged instead of
letting them hit Unhandled (02/H5).
- DbHealthProbeActor runs its SELECT on the thread pool and pipes the
outcome back (single-flight), with a 2 s command timeout on relational
providers, so a hung SQL Server no longer pins the actor thread and the
cached GetStatus answer stays reachable (02/P7).
- TelemetryLocalHub eviction tombstones are timestamped and swept past a
10 min TTL on the next Evict; a TimeProvider ctor is the test seam (02/L4).
- Tests: ValuePublishes.Single helper replaces the per-value
AttributeValuePublished in CalculationDependencyFlowTests (02/U4, test
half; the production receive is owned by Lane E).
- R05/8 audit: PollGroupEngine.Unsubscribe has no production caller; every
driver already uses UnsubscribeAsync (no change).
Refs #731
Claude-Session: https://claude.ai/code/session_01Ub9hGmYLQvn9XETzw7CMsT
WriteAttribute was a ReceiveAsync, suspending the child's mailbox for the
whole device round-trip (up to 5 s): writes serialised, the second of two
operator writes to a slow device missed the host's 8 s Ask and was
reverted although the device took it, and every data change queued behind
the write. Writes are now a synchronous Receive that launches the device
call on the thread pool (sender captured, reply from the task, slot freed
by a self-sent WriteCompleted) under a per-driver cap (default 4; excess
writes queue in order). Queued writes fail fast on every exit from
Connected. Subscribe/unsubscribe stay ReceiveAsync.
Review ref: 02/P2.
Refs #731
Claude-Session: https://claude.ai/code/session_01Ub9hGmYLQvn9XETzw7CMsT
Review R08:1.1: an uncapped HistoryRead-Raw (NumValuesPerNode = 0) read a
tag's whole window into memory on every backend (SQL TOP(int.MaxValue),
QuestDB LIMIT, Gateway max_values = int.MaxValue + a second snapshot copy).
New ServerHistorian:MaxRawValuesPerRead (default 10 000; <= 0 unbounded with
a Validate() warning; 1 raised to 2). Each backend data source takes it,
reports it as IHistorianDataSource.MaxRawValuesPerRead (the Gateway: min
with a strict gateway's learned ceiling), so the node manager's existing
RawPageLimit paging serves N = 0 and N > cap as pages of at most the cap
with a continuation point. Independently, a backend raw read asking for 0
or more than the cap reads cap + 1 rows and is REFUSED
(HistoryReadLimitExceededException => BadTooManyOperations) when the window
holds more - never answered truncated, since the server's paging reads a
short answer as the last page. Bound through the Host registry, the
SqlServer/QuestDb providers and GatewayHistorian.CreateDataSource.
Tests: options (default/binding/warnings), provider binding, Gateway unit +
through a real SDK node manager (uncapped -> 999/998/998/605 + CPs), and a
conformance case for the SQL backends.
Refs #736
Claude-Session: https://claude.ai/code/session_01Ub9hGmYLQvn9XETzw7CMsT
The Reconnecting retry timer started a new ShutdownAsync + InitializeAsync
pair on every tick whether or not the previous attempt had finished; the
generation token only discarded the older RESULT, so with an Initialize
bound longer than the cadence the teardown ran underneath an attempt still
inside the driver (the dispose-before-overwrite race). An _initInFlight
gate, cleared by the piped InitializeSucceeded/Failed, skips a tick while
an attempt is running; the pre-reconnect teardown is bounded by the
shutdown timeout; PostStop cancels an in-flight attempt before shutting
the driver down.
Review ref: 02/H2.
Refs #731
Claude-Session: https://claude.ai/code/session_01Ub9hGmYLQvn9XETzw7CMsT
DriverInstanceActor.PostStop now bounds IDriver.ShutdownAsync by a
shutdownTimeout (default 5 s, logged on overrun) and then disposes the
driver (IAsyncDisposable preferred, else IDisposable) — but only on a
real stop. PreRestart flags the restart so the PostStop it triggers
skips the dispose, because a supervision restart re-uses the same
driver object (Props closure) and the host re-initialises it.
DiscoveryDriverBrowser disposes its throwaway capture/probe driver
after the bounded shutdown, including after a failed or timed-out one.
Review refs: 02/L1, 02/P4, 06/G-1 (host context), 07/L2.
Refs #731
Claude-Session: https://claude.ai/code/session_01Ub9hGmYLQvn9XETzw7CMsT
Keeps the root CLAUDE.md lean by lazy-loading per-area detail (drivers, topology,
data-plane auth, alarms, historian) only when matching files are touched.
Clears CommentChecker findings in src/ (3,280 -> 209, the remainder being false
positives like PLC-5/IEEE-754/M0.0) by adding missing summaries/params/returns,
normalising inheritdoc usage, and removing Gitea/review tracking IDs while keeping
the rationale they annotated. Comment-only: comment-stripped sources are identical
to the parent commit.