Three write bounds were configured independently: the inbound-write
gateway's 10 s Ask, DriverHostActor's fixed 8 s Ask of the child, and the
child's own write timeout (5 s + up to 2 s grace) with a fixed 8 s queue
budget. An outer Ask that fires first reports the write failed and the node
reverts while the child is still driving the device, so any write timeout
above ~6 s (or a write dequeued late in its 8 s budget) let the device take
a value the client was told failed.
DriverWriteBounds (Runtime) derives them all from DriverWrites:Timeout:
token cancel = Timeout
abandon = Timeout + min(Timeout/2, 2 s) (RunBound)
queue budget = RunBound
child replies <= queue budget + RunBound (ReplyBound)
host Ask = ReplyBound + 1 s
gateway Ask = host Ask + 1 s
Default Timeout is 10 s (the Tier C Write timeout, so no tier default is
capped below its own policy); host Ask 25 s, gateway Ask 26 s. Tier A/B
writes are still cancelled first by their 2 s / 4 s tier timeouts.
- DriverHostActor takes writeBounds + writeClock, spawns children with them,
and runs its Ask deadline as a token on the write clock (Infinite Akka
timeout), so host and child bounds share one clock.
- WriteAttribute gains IssuedAt (write-clock timestamp, stamped by the
host): the queue budget counts mailbox time too, and a write past it is
failed BadTimeout and never started - including on arrival. Stale queued
writes are expired across the whole queue, not only up to a free slot.
- ActorNodeWriteGateway's default Ask = Default.GatewayAsk; the hosted
service passes the configured one.
- Startup validation (Host DriverWriteBoundsBinding, same warn-and-clamp
style as ScriptingOptionsBinding): unparsable / non-positive -> default,
above 5 min -> clamped, and each tier whose default Write timeout exceeds
the write timeout is named in a Warning (its policy would never take
effect). The derived bounds are logged at Information. Per-instance
ResilienceConfig Write overrides arrive with a deployment, so
DriverCapabilityInvokerFactory warns at spawn (writeTimeoutCeiling).
- appsettings.json documents DriverWrites:Timeout.
Tests (manual clock):
- DriverHostActorWriteAskTests: a held write under a 9 s timeout survives
an 8.5 s step and succeeds; a token-ignoring write is answered by the
child's BadTimeout at 9 s + grace, not by the Ask; the Infinite-timeout
Ask ends exactly at its clock deadline.
- DriverInstanceActorConcurrentWriteTests: a write issued longer ago than
the queue budget is failed and never reaches the driver; positive control
at exactly the budget is written.
- DriverWriteBoundsTests: every outer bound covers the inner ones for 0.5 s
to 300 s timeouts.
- DriverWriteBoundsBindingTests: default fits every tier; 3 s timeout is
caught at startup with Tier B and C named (not A); bad values fall back
with a warning; over-max clamps.
- DriverCapabilityInvokerFactoryTests: spawn warns when a Write override
exceeds the ceiling; no warning within it or without a ceiling.
Mutation checks: a fixed 8 s host Ask on the same clock fails both 9 s host
tests; stamping arrival time instead of IssuedAt fails the issued-at test;
dropping the tier check / factory check fails their tests.
Runtime.Tests 961 passed / 3 skipped at AKKA_TEST_TIMEFACTOR 3 and 1;
Host.Tests 232/232 at 3 and 1; Core.Tests 361 passed / 1 skipped.
Solution Release build: 0 warnings.
ContinuousHistorizationRecorderTypedValueTests (historian) deliberately
left for the historian lane.
Claude-Session: https://claude.ai/code/session_01GT67AEHd2Acv1YPwGfXEoV
H1 (HIGH): write-routing key now (AddressSpaceRealm, bareId), not bare-only.
A raw s=<RawPath> and a UNS s=<Area/Line/Equip/Eff> can collide as bare
strings; the bare-only key let a colliding raw+UNS pair route to the WRONG
driver ref (last-writer-wins). The realm the node manager resolves (RealmOf)
is now threaded through IOpcUaNodeWriteGateway.WriteAsync -> RouteNodeWrite ->
_driverRefByNodeId keyed by (realm, bareId). New regression test:
Colliding_raw_and_uns_bare_ids_route_to_their_own_driver_by_realm.
M1 (MEDIUM): discovered-node injection made coherently DORMANT. HandleDiscoveredNodes
hard-short-circuits (single enforcement point; _discoveredByDriver never
populates so the re-inject tail is inert too), with a clear log pointing at the
/raw browse-commit flow. New pin: Discovered_nodes_are_ignored_dormant_in_v3;
the 16+2 v2 injection scenarios re-pointed to an accurate skip reason
(DiscoveryInjectionDormantV3).
M2 (MEDIUM): realm-qualified dual-node self-correction tests —
Failed_uns_write_reverts_uns_node_and_leaves_raw_node_untouched +
Raw_realm_revert_reverts_raw_node_only (the second fails if the realm is dropped).
L1: removed the = AddressSpaceRealm.Uns defaults from the consequential
node-manager mutation methods (WriteValue/WriteAlarmCondition/MaterialiseAlarmCondition/
EnsureFolder/EnsureVariable/UpdateFolderDisplayName/UpdateTagAttributes/
RaiseNodesAddedModelChange/Remove*/RevertOptimisticWriteIfNeeded) + the
AttributeValueUpdate/AlarmStateUpdate records, so the compiler forces explicit
realm; read-only accessors + internal builders retain their defaults.
L3: fixed the stale VirtualTagHostActor class comment (V3NodeIds.Uns, not the
retired EquipmentNodeIds.Variable).
Also: DeploymentArtifactRawUnsParityTests — Raw/UNS node-set byte-parity
round-trip between AddressSpaceComposer.Compose and DeploymentArtifact.ParseComposition.
Claude-Session: https://claude.ai/code/session_01LVneM3eh1UtJxEisFXgmox
Joseph Doherty