diff --git a/.claude/rules/data-plane-auth.md b/.claude/rules/data-plane-auth.md
index 62a185a44..3268b7f18 100644
--- a/.claude/rules/data-plane-auth.md
+++ b/.claude/rules/data-plane-auth.md
@@ -212,9 +212,12 @@ Two things to know before relying on any of this:
`OnConditionReportEvent`) — a deferred event of a removed/replaced condition is dropped, never a ghost on `i=2253`;
per-CONDITION ordered queues on overflow; coalesce past 1024/condition or 65 536 total (oldest not-started gives way
to newest); Warning/Information + `otopcua.opcua.condition_events.{deferred,discarded}`. A Server-object ConditionRefresh
- (and ConditionRefresh2) takes a sequence CUT in one `Lock` hold and withholds older deferred events from THAT item
- only (re-sent condition, or a Retain=true event of an omitted one) under a per-item gate held across check+QueueEvent
- (#854, `ConditionRefreshDeferralWireTests`); folder items keep the residual (SDK channel + memoised verdict). Folder events follow Part 3's shape —
+ (and ConditionRefresh2, #854) with nothing deferred is the plain walk OFF `Lock`; while deferring it takes a sequence
+ CUT (one short `Lock` hold: watermark + frozen snapshots of Retain conditions from `_alarmConditions`), queues the
+ replay off `Lock` one event per hold of a per-item gate, and withholds older deferred events from THAT item only
+ (re-sent condition, or Retain=true of one omitted because NOT retained — never one omitted by ACL). Item state is a
+ `ConditionalWeakTable` keyed by the item; cuts clear when the deferral count hits 0. Tests:
+ `ConditionRefreshDeferralWireTests`; folder items keep the residual (SDK channel + memoised verdict). Folder events follow Part 3's shape —
`ReceiveEvents` on EventType + SourceNode (SDK check, kept first) AND our decision; non-condition events on a
folder item fail closed under enforcement. Tests: `FolderEventFloodWireTests`.
- **ns=0 standard nodes stay ungated by design, even with `Security:Acl:Enabled`** (#617) — `ServerStatus`,
diff --git a/docs/security.md b/docs/security.md
index 5c6d21880..3e15eeb37 100644
--- a/docs/security.md
+++ b/docs/security.md
@@ -885,16 +885,33 @@ Behaviours worth knowing before enabling it:
- **`ConditionRefresh` is not overtaken by deferred events on Server-object items (Gitea #854).** A refresh of an
`i=2253` item replays each condition's current state between RefreshStart and RefreshEnd; the condition's deferred
events — all older — used to follow RefreshEnd, briefly showing a stale state or re-adding an alarm the refresh had
- just dropped (ScadaBridge's snapshot swap drops absent conditions, then a stale active event re-added it). Now every
- condition event carries its report sequence; the refresh takes its **cut** (the sequence, whether anything is
- deferred, the replay, and its queueing) in **one hold of `Lock`**, so the replay is exactly the state at the cut, and
- installs it per item under that item's gate, which a deferred delivery also holds across its check and
- `QueueEvent`. A deferred event at or below the cut is withheld **from that item only** when the refresh re-sent its
- condition, or when it is `Retain=true` for a condition the refresh omitted; an older `Retain=false` event of an
- omitted condition still arrives (it agrees with the omission, and a client that does not reconcile on RefreshEnd
- needs it). The deferral queues, every other Server-object item and every folder item are untouched; the refresh never
- waits for a drain. Meter: `otopcua.opcua.condition_events.superseded` (per item and event). Both ConditionRefresh and
- ConditionRefresh2, flag on and off.
+ just dropped (ScadaBridge's snapshot swap drops absent conditions, then a stale active event re-added it). Every
+ condition event now carries its report sequence. Two paths, chosen per refresh:
+ - **Nothing deferred (the common case): unchanged and off `Lock`.** The SDK-shaped notifier walk, queued as live
+ condition nodes; `Lock` is taken only to copy the root-notifier list. It stands only if no deferral episode existed
+ at any moment of it (deferral count zero before and after, episode number unchanged); otherwise the cut path runs
+ too, and its replay — later in the same RefreshStart..RefreshEnd — supersedes anything that slipped in between.
+ - **Deferring: the cut.** ACL/role verdicts first, off `Lock`. Then ONE short `Lock` hold takes the sequence
+ watermark and a frozen snapshot of each Retain condition straight from the condition map (O(conditions), no tree
+ walk), and installs per item, under that item's gate, the **cut** plus a "replay pending" marker. The replay is
+ queued **off `Lock`**, one event per hold of the item gate. While the marker is set, every condition event to the
+ item takes the gate: one newer than the cut marks its condition so the older frozen entry is dropped instead of
+ following it; a deferred one at or below the cut is withheld **from that item only** when the refresh re-sent its
+ condition, or when it is `Retain=true` for a condition the refresh omitted **because it was not retained**. An
+ older `Retain=false` event of such a condition still arrives (it agrees with the omission), and a condition that was
+ retained but omitted for the item's **grants** is never withheld (a grant added before the drain lets its events
+ through; the ACL decides them at delivery as ever).
+ - The deferral queues, every other Server-object item and every folder item are untouched. A refresh waits for the
+ drain at most for one in-progress `QueueEvent` on that item (the gate), never for the drain itself; a reporter
+ holding `Lock` likewise waits at most for one. Each item keeps one gate/cut state for its lifetime (keyed by the
+ item, so an unsubscribe + resubscribe keeps it), and cuts are cleared when the deferral count returns to zero.
+ The custom refresh is refused (`ObjectDisposedException`) once the node manager is disposing, and disposal waits
+ for refreshes in flight, as the base's private operation guard does. Meter:
+ `otopcua.opcua.condition_events.superseded` (per item and event). ConditionRefresh and ConditionRefresh2, flag
+ on and off.
+ - **Measured** (3000 retained conditions, longest `Lock` wait another thread saw during one refresh): the first
+ #854 cut (`1622d07f`, everything under `Lock`) 95–106 ms idle / 102–127 ms deferring; now 0–3 ms idle /
+ 23–32 ms deferring (the frozen snapshots).
- ⚠️ **Residual: folder (notifier) items.** A refresh of an item on an equipment/device folder can still be followed
by older events of a condition. Two sources, neither reachable per item: the SDK's own `MonitoredNode2` channel
(up to 4096 events already accepted before the refresh — this exists in the stock SDK too, and in normal operation
@@ -912,8 +929,12 @@ Behaviours worth knowing before enabling it:
`ConditionRefreshDeferralWireTests` (#854) stalls a folder item's SDK lock so its channel fills without `Lock` held,
refreshes the Server-object item (ConditionRefresh and ConditionRefresh2, flag on/off, condition retained or cleared)
and pins that nothing older than the replay follows RefreshEnd while the non-refreshing folder item still receives the
- whole tail; a probe-driven test pins that a refresh waits for a delivery already past its check (fails without the
- item gate); and a stress test runs reports, refreshes and an intermittent stall concurrently.
+ whole tail (also across an unsubscribe + resubscribe of the item, and the cut is cleared after the drain); a
+ probe-driven test pins that a refresh waits for a delivery already past its check (fails without the item gate); an
+ ACL-on test pins that a condition omitted for want of a grant is not withheld once the grant lands; a 3000-condition
+ test measures the `Lock` hold and pins that neither path queues its replay under `Lock`; and a stress test runs
+ reports, refreshes and an intermittent stall concurrently (its stream never goes backwards outside a refresh, and
+ every refresh ends on the newest state delivered).
**Model-change and audit events on the Server object are gated too** (Gitea #588). The node manager's
own server-wide events — `GeneralModelChangeEvent` (NodeAdded / NodeDeleted / DataTypeChanged) and the
diff --git a/src/Server/ZB.MOM.WW.OtOpcUa.OpcUaServer/OtOpcUaNodeManager.cs b/src/Server/ZB.MOM.WW.OtOpcUa.OpcUaServer/OtOpcUaNodeManager.cs
index 4458bb50e..95ceb77d4 100644
--- a/src/Server/ZB.MOM.WW.OtOpcUa.OpcUaServer/OtOpcUaNodeManager.cs
+++ b/src/Server/ZB.MOM.WW.OtOpcUa.OpcUaServer/OtOpcUaNodeManager.cs
@@ -1,5 +1,6 @@
using System.Collections.Concurrent;
using System.Globalization;
+using System.Runtime.CompilerServices;
using Microsoft.Extensions.Logging;
using Microsoft.Extensions.Logging.Abstractions;
using Opc.Ua;
@@ -620,6 +621,10 @@ public sealed class OtOpcUaNodeManager : CustomNodeManager2, INodeManager3
{
if (disposing)
{
+ // #854 review: refuse new Server-object refreshes and let the ones in flight finish (the base's private
+ // NodeManagerOperation guard does this for its own paths).
+ _disposing = true;
+ SpinWait.SpinUntil(() => Volatile.Read(ref _refreshesInFlight) == 0, TimeSpan.FromSeconds(10));
Volatile.Read(ref _dataPlaneAuthority).Changed -= OnAuthorityChanged;
_liveItems.Clear();
_eventItems.Clear();
@@ -1554,19 +1559,30 @@ public sealed class OtOpcUaNodeManager : CustomNodeManager2, INodeManager3
_logger.LogError(ex, "OtOpcUaNodeManager: failed to report Part 9 condition event for {NodeId}", condition.NodeId);
}
- IFilterTarget next;
+ IFilterTarget? next = null;
+ var episodeEnded = false;
lock (_eventReportGate)
{
CountDeferred(-1, condition);
if (queue.Pending.Count == 0)
{
_deferredReports.Remove(condition);
- return;
+ episodeEnded = _deferredEventReports == 0;
+ }
+ else
+ {
+ next = queue.Pending.Dequeue();
}
-
- next = queue.Pending.Dequeue();
}
+ if (episodeEnded)
+ {
+ ClearStaleRefreshCuts();
+ return;
+ }
+
+ if (next is null) return;
+
try
{
current = DeliverConditionEventAsync(condition, condition, next).AsTask();
@@ -1641,7 +1657,14 @@ public sealed class OtOpcUaNodeManager : CustomNodeManager2, INodeManager3
condition.NodeId, MaxDeferredEventsPerCondition);
}
}
- else if (_deferredEventReports == 0 && before > 0 && _episodeWarned)
+ if (_deferredEventReports == 0 && before > 0)
+ {
+ // #854: every deferred event has been delivered, so no refresh cut taken during this episode can match
+ // anything any more; a new number makes them all stale at once (see RefreshCut.Episode).
+ _deferralEpisode++;
+ }
+
+ if (_deferredEventReports == 0 && before > 0 && _episodeWarned)
{
_logger.LogInformation(
"OtOpcUaNodeManager: deferred condition events drained ({Deferred} deferred, {Discarded} discarded this episode)",
@@ -1704,21 +1727,94 @@ public sealed class OtOpcUaNodeManager : CustomNodeManager2, INodeManager3
/// Under .
public RefreshCut? Cut;
+
+ ///
+ /// The refresh whose frozen replay is being queued to the item (0 = none). Set under Lock AND the gate
+ /// at the cut; cleared under the gate once queued. While set, every condition event delivered to the item
+ /// takes the gate, and one newer than the cut marks its condition in so the replay
+ /// does not follow it with an older state.
+ ///
+ public volatile int PendingReplay;
+
+ /// Under : the watermark of .
+ public long PendingWatermark;
+
+ /// Under : conditions an event newer than the pending replay already reached.
+ public readonly HashSet NewerSinceCut = [];
}
+ private int _refreshGeneration;
+
+ ///
+ /// One per Server-object item for the item's whole lifetime (#854 review): keyed by
+ /// the item object itself, so an unsubscribe + resubscribe of the same item between a refresh and the drain keeps its
+ /// cut and its gate, and a drain holding the state always holds the one a refresh installs into.
+ ///
+ private readonly ConditionalWeakTable _allEventsItemStates = new();
+
+ /// Server-object items currently holding a refresh cut (test observation, #854 review).
+ internal int ActiveRefreshCuts
+ {
+ get
+ {
+ var n = 0;
+ foreach (var item in _allEventsItems.Keys)
+ {
+ if (!_allEventsItemStates.TryGetValue(item, out var state)) continue;
+ lock (state.Gate) n += state.Cut is null ? 0 : 1;
+ }
+
+ return n;
+ }
+ }
+
+ private AllEventsItemState AllEventsItemStateOf(IEventMonitoredItem item) =>
+ _allEventsItemStates.GetValue(item, static _ => new AllEventsItemState());
+
+ ///
+ /// Advanced (under the event-report gate) each time the deferral count returns to zero: the end of a deferral
+ /// episode, after which no event a cut could withhold is still undelivered (#854 review).
+ ///
+ private long _deferralEpisode;
+
/// What a Server-object item's latest ConditionRefresh conveyed (#854).
/// Every condition event with a sequence at or below this was reported before the replay was read.
- /// The conditions the replay re-sent to the item; the others were Retain=false (or not visible).
- private sealed record RefreshCut(long Watermark, HashSet Refreshed)
+ /// The deferral episode the cut was taken in; once it ends the cut is stale and inert.
+ /// The conditions the replay re-sent to THIS item.
+ /// Every condition that was Retain at the watermark, whether or not this item was sent it
+ /// (one set shared by every item of the refresh).
+ private sealed record RefreshCut(long Watermark, long Episode, HashSet Refreshed, HashSet RetainedAtCut)
{
///
- /// Whether the refresh already told the item something at least as new as : a re-sent
- /// condition's current state supersedes every older event of it; for a condition the replay OMITTED (it was not
- /// retained), an older Retain=true event would wrongly re-add it, while an older Retain=false event agrees with
- /// the omission and is still delivered (a client that did not reconcile on RefreshEnd needs it).
+ /// Whether the refresh already told the item something at least as new as . A re-sent
+ /// condition: its replayed state supersedes every older event of it. A condition the replay omitted because it
+ /// was NOT retained: an older Retain=true event would wrongly re-add it, so it is withheld; an older Retain=false
+ /// event agrees with the omission and is delivered (a client that did not reconcile on RefreshEnd needs it). A
+ /// condition that WAS retained but was omitted for this item (ACL / role at refresh time): never withheld — the
+ /// refresh told the item nothing about it, so a grant added before the drain still lets its events through
+ /// (decided by the ACL at delivery, as ever).
///
public bool Supersedes(ConditionEventSnapshot e) =>
- e.Sequence <= Watermark && (e.Retain || Refreshed.Contains(e.ConditionId));
+ e.Sequence <= Watermark
+ && (Refreshed.Contains(e.ConditionId) || (e.Retain && !RetainedAtCut.Contains(e.ConditionId)));
+ }
+
+ ///
+ /// Drops every refresh cut taken in an episode that has ended (#854 review), so a cut does not outlive the events it
+ /// guards. Called by the drain after the deferral count reached zero, holding no lock; a cut installed concurrently
+ /// for the new episode is kept.
+ ///
+ private void ClearStaleRefreshCuts()
+ {
+ var current = Interlocked.Read(ref _deferralEpisode);
+ foreach (var item in _allEventsItems.Keys)
+ {
+ if (!_allEventsItemStates.TryGetValue(item, out var state)) continue;
+ lock (state.Gate)
+ {
+ if (state.Cut is { } cut && cut.Episode != current) state.Cut = null;
+ }
+ }
}
@@ -5362,7 +5458,7 @@ public sealed class OtOpcUaNodeManager : CustomNodeManager2, INodeManager3
/// unsubscribe arms, which the SDK's MasterNodeManager drives for every create, modify,
/// transfer, restore and delete of an all-events item, subscription teardown included.
///
- private readonly ConcurrentDictionary _allEventsItems = new();
+ private readonly ConcurrentDictionary _allEventsItems = new();
// The SDK's base implementation attaches a Server-object item to the event
// fan-out of every one of this manager's root notifiers, so every alarm in the server reached it
@@ -5384,7 +5480,7 @@ public sealed class OtOpcUaNodeManager : CustomNodeManager2, INodeManager3
lock (Lock)
{
if (unsubscribe) _allEventsItems.TryRemove(monitoredItem, out _);
- else _allEventsItems.GetOrAdd(monitoredItem, static _ => new AllEventsItemState());
+ else _allEventsItems[monitoredItem] = 0;
ReconcileAllEventsMonitoring();
}
@@ -5560,7 +5656,7 @@ public sealed class OtOpcUaNodeManager : CustomNodeManager2, INodeManager3
var reportingSession = (context as ISessionSystemContext)?.SessionId;
var deferred = e is ConditionEventSnapshot { Deferred: true } d ? d : null;
- foreach (var (item, state) in _allEventsItems)
+ foreach (var item in _allEventsItems.Keys)
{
if (e is AuditEventState && !IsAuditDeliverableTo(item)) continue;
if (scopes is not null && !IsConditionVisibleTo(item, scopes)) continue;
@@ -5572,25 +5668,36 @@ public sealed class OtOpcUaNodeManager : CustomNodeManager2, INodeManager3
continue;
}
- if (deferred is null)
+ // #854: a synchronous event (under Lock) needs the gate only while a refresh's replay is pending, and the
+ // pending marker is installed under Lock, so an item no refresh has touched has nothing to order. A deferred
+ // event always takes the gate — its state is created here if need be, so a refresh racing it shares it.
+ AllEventsItemState? state;
+ if (deferred is not null) state = AllEventsItemStateOf(item);
+ else if (!_allEventsItemStates.TryGetValue(item, out state) || state.PendingReplay == 0 || e is not ConditionEventSnapshot)
{
item.QueueEvent(e);
continue;
}
- // #854: a deferred event reaches this item off Lock, so a ConditionRefresh of the item may have replayed a
- // newer state since it was reported. Decided and queued under the item's gate, which the refresh holds while
- // it queues its replay and installs its cut — so it lands either before the replay or not at all.
+ // A deferred event reaches this item off Lock, so a ConditionRefresh of the item may have replayed a newer
+ // state since it was reported; and while a refresh's frozen replay is being queued, an event newer than it must
+ // not be followed by it. Both are decided and queued under the item's gate, which the refresh also holds for
+ // each replayed event it queues — so a deferred event lands before the replay or is judged against the cut.
lock (state.Gate)
{
- if (state.Cut?.Supersedes(deferred) == true)
+ // A cut from an episode that has ended is stale (only waiting for ClearStaleRefreshCuts).
+ if (deferred is not null
+ && state.Cut is { } cut && cut.Episode == Interlocked.Read(ref _deferralEpisode) && cut.Supersedes(deferred))
{
Interlocked.Increment(ref _refreshSupersededDeliveries);
OtOpcUaTelemetry.ConditionEventDeliveriesSuperseded.Add(1);
continue;
}
- DeferredServerObjectDeliveryProbe?.Invoke();
+ if (state.PendingReplay != 0 && e is ConditionEventSnapshot { } ce && ce.Sequence > state.PendingWatermark)
+ state.NewerSinceCut.Add(ce.ConditionId);
+
+ if (deferred is not null) DeferredServerObjectDeliveryProbe?.Invoke();
item.QueueEvent(e);
}
}
@@ -6174,26 +6281,47 @@ public sealed class OtOpcUaNodeManager : CustomNodeManager2, INodeManager3
///
public override ServiceResult ConditionRefresh(OperationContext context, IList monitoredItems)
{
- var direct = new List();
- var serverItems = new List();
- foreach (var item in monitoredItems)
+ // The base's NodeManagerOperation guard is private; this is its equivalent for the custom paths (#854 review):
+ // refused once disposal starts, and Dispose waits for the ones in flight.
+ Interlocked.Increment(ref _refreshesInFlight);
+ try
{
- if (item is null) continue;
- (item.NodeId == ObjectIds.Server ? serverItems : direct).Add(item);
- }
+ if (_disposing) throw new ObjectDisposedException(GetType().Name);
- var enforced = AclEnforced;
- var systemContext = SystemContext.Copy(context);
- if (direct.Count > 0)
+ var direct = new List();
+ var serverItems = new List();
+ foreach (var item in monitoredItems)
+ {
+ if (item is null) continue;
+ (item.NodeId == ObjectIds.Server ? serverItems : direct).Add(item);
+ }
+
+ var enforced = AclEnforced;
+ var systemContext = SystemContext.Copy(context);
+ if (direct.Count > 0)
+ {
+ if (enforced) RefreshDirectItems(systemContext, direct);
+ else base.ConditionRefresh(context, direct);
+ }
+
+ if (serverItems.Count > 0) RefreshServerObjectItems(systemContext, serverItems, enforced);
+ return ServiceResult.Good;
+ }
+ finally
{
- if (enforced) RefreshDirectItems(systemContext, direct);
- else base.ConditionRefresh(context, direct);
+ Interlocked.Decrement(ref _refreshesInFlight);
}
-
- if (serverItems.Count > 0) RefreshServerObjectItems(systemContext, serverItems, enforced);
- return ServiceResult.Good;
}
+ private int _refreshesInFlight;
+ private volatile bool _disposing;
+
+ ///
+ /// Test probe (#854 review): called once per Server-object refresh with whether it took the cut path and whether
+ /// the calling thread held Lock while it queued the replay. Null in production.
+ ///
+ internal Action? ServerObjectRefreshProbe { get; set; }
+
///
/// ConditionRefresh (and ConditionRefresh2) for Server-object (i=2253) items: each condition under a root
/// notifier once, through the item's ACL decision when (#586) — and never overtaken by
@@ -6211,84 +6339,224 @@ public sealed class OtOpcUaNodeManager : CustomNodeManager2, INodeManager3
/// refresh had just dropped re-added, until the newest drained.
///
///
- /// The cut. Everything — the watermark (), whether any event is
- /// deferred, the replay itself and its queueing — happens in ONE hold of Lock, under which every condition
- /// event is reported. So the replay is exactly the state at the watermark: an event at or below it is not newer
- /// than the replay, one above it was reported after it. Each item's replay is queued and its
- /// installed under the item's , which a deferred
- /// delivery to the item also holds (): a deferred event therefore lands
- /// before the replay, or is judged against the cut — withheld if superseded ().
- /// Only events marked are judged: any other was delivered to
- /// Server-object items synchronously under Lock, so it cannot follow a replay it predates.
+ /// Common case — nothing deferred: unchanged, and off Lock. The replay is the notifier walk the SDK
+ /// base does, queued as live condition nodes, with Lock taken only to copy the root-notifier list. It is
+ /// kept only if no deferral episode existed at any moment of it: the deferral count is zero before AND after and
+ /// the episode number () did not move. Otherwise a deferred event may have reached
+ /// the item after the replay, so the cut path below runs as well — its second replay, queued later inside the
+ /// same RefreshStart/RefreshEnd, supersedes anything that slipped in between.
+ ///
+ ///
+ /// Deferring — the cut. In ONE hold of Lock (under which every condition event is reported): the
+ /// watermark (), the episode, and a frozen snapshot of each Retain
+ /// condition read from (O(conditions), no tree walk), then queued to each item
+ /// with its installed under the item's . The ACL /
+ /// role verdicts are computed BEFORE taking Lock, against the live conditions (they depend on the event
+ /// type and source, not state). The cut and a "replay pending" marker are installed per item under its
+ /// inside that Lock hold; the replay is then queued OFF
+ /// Lock, one event per hold of the gate. While the marker is set every condition event to the item takes
+ /// the gate: one newer than the cut marks its condition so its (older) frozen replay entry is dropped instead of
+ /// following it; a deferred one at or below the cut is judged against the cut ()
+ /// — it lands before the replay entry or not at all.
///
///
/// Per item, never global. Only the refreshed item stops receiving the superseded events; the deferral
- /// queue, every other Server-object item and every folder item still get them, in order. The refresh never
- /// waits for a drain. No cut is kept while nothing is deferred (the common case).
+ /// queue, every other Server-object item and every folder item still get them, in order. A refresh waits for a
+ /// drain at most for one in-progress QueueEvent on that item (the gate), never for the drain itself.
+ /// Cuts die with their episode ().
///
///
/// Lock order is Lock → item gate → the SDK item's own lock, the same as a synchronous report
- /// (Lock → ); the drain takes the item gate without Lock, and
- /// nothing under an item gate takes Lock or the event-report gate.
+ /// (Lock → ); the drain and the replay queueing take the item gate
+ /// without Lock, and nothing under an item gate takes Lock or the event-report gate. A gate is held
+ /// for one QueueEvent at a time, so a reporter holding Lock waits at most for one.
///
///
/// With enforcement off this replaces the SDK base's Server-object loop with the same result: the base queued
/// one copy per root notifier a condition is wired to, which the item's queue collapsed to one (they share an
/// EventId); here it is one per condition. A replayed event that names no condition is withheld only under
- /// enforcement (fail closed), as before.
+ /// enforcement (fail closed), as before. The cut path replays from , which holds
+ /// every condition this manager materialises (all of them sit under a root notifier); branches are replayed as
+ /// the SDK's ConditionState.ConditionRefresh lists them.
///
///
private void RefreshServerObjectItems(ServerSystemContext systemContext, List items, bool enforced)
{
- lock (Lock)
+ long episodeBefore;
+ bool deferringBefore;
+ lock (_eventReportGate)
{
- var watermark = Interlocked.Read(ref _conditionEventSequence);
- bool deferring;
- lock (_eventReportGate) deferring = _deferredEventReports > 0;
+ episodeBefore = _deferralEpisode;
+ deferringBefore = _deferredEventReports > 0;
+ }
+ if (!deferringBefore)
+ {
+ List notifiers;
+ lock (Lock) notifiers = RootNotifiers?.ToList() ?? [];
var events = new List();
- foreach (var notifier in RootNotifiers?.ToList() ?? []) notifier.ConditionRefresh(systemContext, events, true);
-
- // One event per condition, with its scopes resolved once.
- var replay = new List<(IFilterTarget Event, NodeState? Condition, List? Scopes)>();
- var seen = new HashSet(System.Collections.Generic.ReferenceEqualityComparer.Instance);
- foreach (var e in events)
- {
- if (ConditionOf(e) is not { } condition)
- {
- if (!enforced) replay.Add((e, null, null));
- continue;
- }
-
- if (!seen.Add(condition)) continue;
- replay.Add((e, condition, enforced ? ConditionVisibilityScopes(condition) : null));
- }
+ foreach (var notifier in notifiers) notifier.ConditionRefresh(systemContext, events, true);
+ var replay = DedupeReplay(events, enforced);
+ ServerObjectRefreshProbe?.Invoke(false, Monitor.IsEntered(Lock));
foreach (var item in items)
{
- var queued = new List();
- var refreshed = new HashSet();
- foreach (var (e, condition, scopes) in replay)
+ // A cut-path replay of this item still being queued by a concurrent refresh is older than this live one:
+ // stop it, so it cannot follow this replay with frozen states.
+ if (_allEventsItemStates.TryGetValue(item, out var pending))
+ {
+ lock (pending.Gate)
+ {
+ pending.PendingReplay = 0;
+ pending.NewerSinceCut.Clear();
+ }
+ }
+
+ foreach (var (e, _, scopes) in replay)
{
if (scopes is not null && !IsConditionVisibleTo(item, scopes)) continue;
if (ServiceResult.IsBad(ValidateEventRolePermissions(item, e))) continue;
- queued.Add(e);
- if (condition is not null) refreshed.Add(condition.NodeId);
+ item.QueueEvent(e);
}
+ }
- if (!_allEventsItems.TryGetValue(item, out var state))
+ lock (_eventReportGate)
+ {
+ if (_deferralEpisode == episodeBefore && _deferredEventReports == 0) return;
+ }
+ }
+
+ RefreshServerObjectItemsWithCut(systemContext, items, enforced);
+ }
+
+ /// One replay entry per condition (the first the walk produced), with its ACL scopes resolved once.
+ private List<(IFilterTarget Event, NodeState? Condition, List? Scopes)> DedupeReplay(
+ List events, bool enforced)
+ {
+ var replay = new List<(IFilterTarget Event, NodeState? Condition, List? Scopes)>();
+ var seen = new HashSet(System.Collections.Generic.ReferenceEqualityComparer.Instance);
+ foreach (var e in events)
+ {
+ if (ConditionOf(e) is not { } condition)
+ {
+ if (!enforced) replay.Add((e, null, null));
+ continue;
+ }
+
+ if (!seen.Add(condition)) continue;
+ replay.Add((e, condition, enforced ? ConditionVisibilityScopes(condition) : null));
+ }
+
+ return replay;
+ }
+
+ /// The cut path of — see there.
+ private void RefreshServerObjectItemsWithCut(ServerSystemContext systemContext, List items, bool enforced)
+ {
+ // ACL / role verdicts per (item, condition) before Lock: they depend on the event type, source and grants only.
+ List conditions;
+ lock (Lock) conditions = [.. _alarmConditions.Values];
+ var known = new HashSet(conditions, System.Collections.Generic.ReferenceEqualityComparer.Instance);
+ var allowed = new HashSet<(IEventMonitoredItem, AlarmConditionState)>();
+ foreach (var condition in conditions)
+ {
+ var scopes = enforced ? ConditionVisibilityScopes(condition) : null;
+ foreach (var item in items)
+ {
+ if (scopes is not null && !IsConditionVisibleTo(item, scopes)) continue;
+ if (ServiceResult.IsBad(ValidateEventRolePermissions(item, condition))) continue;
+ allowed.Add((item, condition));
+ }
+ }
+
+ var states = items.Select(AllEventsItemStateOf).ToList();
+ var perItem = new List<(IFilterTarget Event, AlarmConditionState Condition)>[items.Count];
+ var generation = Interlocked.Increment(ref _refreshGeneration);
+ lock (Lock)
+ {
+ var watermark = Interlocked.Read(ref _conditionEventSequence);
+ long episode;
+ bool deferring;
+ lock (_eventReportGate)
+ {
+ episode = _deferralEpisode;
+ deferring = _deferredEventReports > 0;
+ }
+
+ // Frozen at the watermark: the replay is exactly the state every event at or below it describes.
+ var retained = new HashSet();
+ var replay = new List<(IFilterTarget Event, AlarmConditionState Condition)>();
+ var branches = new List();
+ foreach (var condition in _alarmConditions.Values)
+ {
+ if (condition.Retain?.Value != true) continue;
+ retained.Add(condition.NodeId);
+ branches.Clear();
+ condition.ConditionRefresh(SystemContext, branches, true);
+ foreach (var target in branches)
{
- // Not (or no longer) subscribed: no deferred delivery can reach it, so there is nothing to cut.
- foreach (var e in queued) item.QueueEvent(e);
- continue;
+ if (target is not BaseInstanceState instance) continue;
+ var snapshot = new InstanceStateSnapshot();
+ snapshot.Initialize(SystemContext, instance);
+ replay.Add((snapshot, condition));
+ }
+ }
+
+ for (var i = 0; i < items.Count; i++)
+ {
+ var item = items[i];
+ var entries = new List<(IFilterTarget Event, AlarmConditionState Condition)>();
+ var refreshed = new HashSet();
+ foreach (var (e, condition) in replay)
+ {
+ // A condition materialised since the verdicts were taken is decided here (rare).
+ if (!allowed.Contains((item, condition)))
+ {
+ if (known.Contains(condition)) continue;
+ if (enforced && !IsConditionVisibleTo(item, ConditionVisibilityScopes(condition))) continue;
+ if (ServiceResult.IsBad(ValidateEventRolePermissions(item, e))) continue;
+ }
+
+ entries.Add((e, condition));
+ refreshed.Add(condition.NodeId);
}
+ perItem[i] = entries;
+ var state = states[i];
lock (state.Gate)
{
- foreach (var e in queued) item.QueueEvent(e);
- // A cut is only needed while an event at or below the watermark may still be delivered. Refreshes are
- // serialised by Lock, so a later one always carries the later watermark and simply replaces it.
- state.Cut = deferring ? new RefreshCut(watermark, refreshed) : null;
+ state.Cut = deferring ? new RefreshCut(watermark, episode, refreshed, retained) : null;
+ state.PendingWatermark = watermark;
+ state.NewerSinceCut.Clear();
+ state.PendingReplay = generation;
+ }
+ }
+ }
+
+ // Queued off Lock, one replayed event per hold of the item gate: an event that reached the item since the cut is
+ // newer than the frozen replay of its condition, so that replay entry is dropped rather than queued after it (the
+ // newer event is already inside RefreshStart..RefreshEnd). A later refresh of the item supersedes this one.
+ ServerObjectRefreshProbe?.Invoke(true, Monitor.IsEntered(Lock));
+ for (var i = 0; i < items.Count; i++)
+ {
+ var item = items[i];
+ var state = states[i];
+ foreach (var (e, condition) in perItem[i])
+ {
+ lock (state.Gate)
+ {
+ if (state.PendingReplay != generation) break;
+ if (state.NewerSinceCut.Contains(condition.NodeId)) continue;
+ item.QueueEvent(e);
+ }
+ }
+
+ lock (state.Gate)
+ {
+ if (state.PendingReplay == generation)
+ {
+ state.PendingReplay = 0;
+ state.NewerSinceCut.Clear();
}
}
}
diff --git a/tests/Server/ZB.MOM.WW.OtOpcUa.OpcUaServer.IntegrationTests/ConditionRefreshDeferralWireTests.cs b/tests/Server/ZB.MOM.WW.OtOpcUa.OpcUaServer.IntegrationTests/ConditionRefreshDeferralWireTests.cs
index b1d456e98..29886a6bd 100644
--- a/tests/Server/ZB.MOM.WW.OtOpcUa.OpcUaServer.IntegrationTests/ConditionRefreshDeferralWireTests.cs
+++ b/tests/Server/ZB.MOM.WW.OtOpcUa.OpcUaServer.IntegrationTests/ConditionRefreshDeferralWireTests.cs
@@ -9,6 +9,7 @@ using Xunit;
using ZB.MOM.WW.OtOpcUa.Commons.OpcUa;
using ZB.MOM.WW.OtOpcUa.Configuration.Entities;
using ZB.MOM.WW.OtOpcUa.Configuration.Enums;
+using ZB.MOM.WW.OtOpcUa.Core.Abstractions;
using ZB.MOM.WW.OtOpcUa.Core.Authorization;
using MonitoredItem = Opc.Ua.Client.MonitoredItem;
@@ -40,15 +41,21 @@ public sealed class ConditionRefreshDeferralWireTests
/// (so the refresh omits it and its final Retain=false event must still arrive).
///
/// ConditionRefresh2 on the single item instead of ConditionRefresh on the subscription.
+ ///
+ /// The Server-object item is unsubscribed and resubscribed (the SDK drives this on a monitoring-mode change)
+ /// between the refresh and the drain: its cut must survive (#854 review — it lived in the subscription map entry).
+ ///
[Theory]
- [InlineData(false, true, false)]
- [InlineData(true, true, false)]
- [InlineData(false, false, false)]
- [InlineData(true, false, false)]
- [InlineData(false, true, true)]
- [InlineData(true, false, true)]
+ [InlineData(false, true, false, false)]
+ [InlineData(true, true, false, false)]
+ [InlineData(false, false, false, false)]
+ [InlineData(true, false, false, false)]
+ [InlineData(false, true, true, false)]
+ [InlineData(true, false, true, false)]
+ [InlineData(false, true, false, true)]
+ [InlineData(true, false, false, true)]
public async Task Deferred_events_older_than_a_refresh_never_reach_the_refreshed_server_object_item_after_RefreshEnd(
- bool enforced, bool finalRetained, bool refresh2)
+ bool enforced, bool finalRetained, bool refresh2, bool resubscribe)
{
var ct = TestContext.Current.CancellationToken;
await using var rig = await ServerEventRig.StartAsync("Refresh854", encrypted: false, ct);
@@ -100,10 +107,21 @@ public sealed class ConditionRefreshDeferralWireTests
refresh.Elapsed.ShouldBeLessThan(TimeSpan.FromSeconds(10), "ConditionRefresh must not wait for the stalled drain");
await RecordedEvents.WaitUntilAsync(() => serverEvents.HasType(onServer, ObjectTypeIds.RefreshEndEventType));
rig.Nm.DeferredEventReports.ShouldBeGreaterThan(0, "the deferred events were still waiting at RefreshEnd");
+ rig.Nm.ActiveRefreshCuts.ShouldBe(1);
+ if (resubscribe)
+ {
+ var serverItem = FindAllEventsItem(rig.Nm, onServer.Status.Id);
+ rig.Nm.SubscribeToAllEvents(null!, serverSubscription.Id, serverItem, unsubscribe: true);
+ rig.Nm.SubscribeToAllEvents(null!, serverSubscription.Id, serverItem, unsubscribe: false);
+ }
+
stall.Release();
}
await RecordedEvents.WaitUntilAsync(() => rig.Nm.DeferredEventReports == 0);
+ // #854 review: a cut does not outlive its deferral episode.
+ await RecordedEvents.WaitUntilAsync(() => rig.Nm.ActiveRefreshCuts == 0);
+ rig.Nm.ActiveRefreshCuts.ShouldBe(0, "the cut is cleared when the deferral count returns to zero");
// Positive control: a later transition is delivered (and everything deferred before it has been decided).
rig.Project(native: true, Active("after"));
await RecordedEvents.WaitUntilAsync(() => serverEvents.Has(onServer, "after"));
@@ -149,6 +167,144 @@ public sealed class ConditionRefreshDeferralWireTests
folderEvents.Has(onA, "final").ShouldBeTrue();
}
+ ///
+ /// #854 review (ACL on): a condition the refresh omitted for the item because of its grants — not because it was
+ /// cleared — must not have its deferred events withheld: a grant added before the drain lets them through, and the
+ /// item must end on the condition's newest state (it would otherwise miss an active alarm entirely).
+ ///
+ [Fact]
+ public async Task Deferred_events_of_a_condition_the_refresh_omitted_for_want_of_a_grant_are_not_withheld()
+ {
+ var ct = TestContext.Current.CancellationToken;
+ await using var rig = await ServerEventRig.StartAsync("Refresh854Acl", encrypted: false, ct);
+ rig.KeyRoles = [];
+ rig.MaterialiseNative();
+ var anonymousOnA = ServerEventRig.EquipmentGrant(EqA, NodePermissions.ReadOnly);
+ rig.Enforce(true, [ServerEventRig.Key()], anonymousOnA);
+
+ // The stalled folder subscriber is anonymous (granted EqA); the refreshing key session holds no grant yet.
+ using var folderSession = await rig.ConnectAsync(anonymous: true, ct);
+ var folderEvents = new RecordedEvents();
+ var folderSubscription = await RecordedEvents.SubscribeAsync(folderSession, folderEvents, ct);
+ var onA = RecordedEvents.AddEventItem(folderSubscription, ServerEventRig.UnsNodeId(folderSession, EqA));
+ await folderSubscription.ApplyChangesAsync(ct);
+
+ using var serverSession = await rig.ConnectAsync(anonymous: false, ct);
+ var serverEvents = new RecordedEvents();
+ var serverSubscription = await RecordedEvents.SubscribeAsync(serverSession, serverEvents, ct);
+ var onServer = RecordedEvents.AddEventItem(serverSubscription, ObjectIds.Server);
+ await serverSubscription.ApplyChangesAsync(ct);
+
+ rig.Project(native: true, Active("seed"));
+ await RecordedEvents.WaitUntilAsync(() => folderEvents.Has(onA, "seed"));
+ serverEvents.Has(onServer, "seed").ShouldBeFalse("the key holds no grant yet");
+ await folderSubscription.SetPublishingModeAsync(false, ct);
+
+ using (var stall = ItemLockStall.Hold(FindServerItem(rig.Nm, onA.Status.Id)))
+ {
+ for (var i = 0; i < FloodSize; i++) rig.Project(native: true, Active($"f{i}"));
+ rig.Project(native: true, Active("final"));
+ rig.Nm.DeferredEventReports.ShouldBeGreaterThan(0);
+
+ await serverSession.CallAsync(
+ ObjectTypeIds.ConditionType, MethodIds.ConditionType_ConditionRefresh, ct, serverSubscription.Id);
+ await RecordedEvents.WaitUntilAsync(() => serverEvents.HasType(onServer, ObjectTypeIds.RefreshEndEventType));
+
+ // The grant arrives while the condition's events still wait.
+ rig.Enforce(true, [ServerEventRig.Key()], anonymousOnA, KeyEquipmentGrant(EqA));
+ stall.Release();
+ }
+
+ await RecordedEvents.WaitUntilAsync(() => rig.Nm.DeferredEventReports == 0);
+ await RecordedEvents.WaitUntilAsync(() => serverEvents.Has(onServer, "final"));
+ var stream = serverEvents.Of(onServer).ToList();
+ var end = stream.FindIndex(f => f[RecordedEvents.EventTypeField].GetNodeId() == ObjectTypeIds.RefreshEndEventType);
+ stream.Take(end).Count(f => f[RecordedEvents.AckedField].TryGetValue(out bool _))
+ .ShouldBe(0, "the refresh omitted the condition: no grant");
+ var after = stream.Skip(end + 1)
+ .Where(f => f[RecordedEvents.AckedField].TryGetValue(out bool _))
+ .Select(RecordedEvents.Message)
+ .ToList();
+ after.ShouldNotBeEmpty();
+ after[^1].ShouldBe("final", "the item ends on the newest state of a condition it was never refreshed");
+ after.Count(m => m!.StartsWith('f') && m != "final").ShouldBeGreaterThan(0, "its deferred events were delivered, not withheld");
+ }
+
+ ///
+ /// #854 review: the cut path queues its frozen replay OFF Lock. An event newer than the cut that reaches the
+ /// item in that window (here a synchronously delivered condition, reported from the probe between the cut and the
+ /// queueing) must not be followed by its condition's older frozen replay entry.
+ ///
+ [Fact]
+ public async Task An_event_newer_than_the_cut_is_never_followed_by_its_conditions_older_frozen_replay()
+ {
+ var ct = TestContext.Current.CancellationToken;
+ await using var rig = await ServerEventRig.StartAsync("Refresh854Pending", encrypted: false, ct);
+ rig.KeyRoles = [];
+ rig.MaterialiseNative();
+ rig.Enforce(false, [ServerEventRig.Key()], KeyEquipmentGrant(EqA));
+ // A second condition under the device folder only: no folder item, so its events are always synchronous.
+ const string Free = ServerEventRig.RawDeviceFolder + "/free";
+ rig.Sink.MaterialiseAlarmCondition(Free, ServerEventRig.RawDeviceFolder, "free", "OffNormalAlarm", 700, AddressSpaceRealm.Raw, isNative: true);
+ rig.Sink.WriteAlarmCondition(Free, Active("x1"), DateTime.UtcNow, AddressSpaceRealm.Raw);
+
+ using var folderSession = await rig.ConnectAsync(anonymous: false, ct);
+ var folderEvents = new RecordedEvents();
+ var folderSubscription = await RecordedEvents.SubscribeAsync(folderSession, folderEvents, ct);
+ var onA = RecordedEvents.AddEventItem(folderSubscription, ServerEventRig.UnsNodeId(folderSession, EqA));
+ await folderSubscription.ApplyChangesAsync(ct);
+
+ using var serverSession = await rig.ConnectAsync(anonymous: false, ct);
+ var serverEvents = new RecordedEvents();
+ var serverSubscription = await RecordedEvents.SubscribeAsync(serverSession, serverEvents, ct);
+ var onServer = RecordedEvents.AddEventItem(serverSubscription, ObjectIds.Server);
+ await serverSubscription.ApplyChangesAsync(ct);
+
+ rig.Project(native: true, Active("seed"));
+ await RecordedEvents.WaitUntilAsync(() => folderEvents.Has(onA, "seed") && serverEvents.Has(onServer, "seed"));
+ await folderSubscription.SetPublishingModeAsync(false, ct);
+
+ var injected = 0;
+ rig.Nm.ServerObjectRefreshProbe = (cut, _) =>
+ {
+ if (cut && Interlocked.Exchange(ref injected, 1) == 0)
+ rig.Sink.WriteAlarmCondition(Free, Active("x2"), DateTime.UtcNow, AddressSpaceRealm.Raw);
+ };
+
+ using (var stall = ItemLockStall.Hold(FindServerItem(rig.Nm, onA.Status.Id)))
+ {
+ for (var i = 0; i < FloodSize; i++) rig.Project(native: true, Active($"f{i}"));
+ rig.Nm.DeferredEventReports.ShouldBeGreaterThan(0, "the cut path runs only while something is deferred");
+ await serverSession.CallAsync(
+ ObjectTypeIds.ConditionType, MethodIds.ConditionType_ConditionRefresh, ct, serverSubscription.Id);
+ await RecordedEvents.WaitUntilAsync(() => serverEvents.HasType(onServer, ObjectTypeIds.RefreshEndEventType));
+ stall.Release();
+ }
+
+ rig.Nm.ServerObjectRefreshProbe = null;
+ Volatile.Read(ref injected).ShouldBe(1);
+ var stream = serverEvents.Of(onServer).ToList();
+ var end = stream.FindIndex(f => f[RecordedEvents.EventTypeField].GetNodeId() == ObjectTypeIds.RefreshEndEventType);
+ var free = stream.Take(end)
+ .Select(RecordedEvents.Message)
+ .Where(m => m is "x1" or "x2")
+ .ToList();
+ free.ShouldContain("x2");
+ free[^1].ShouldBe("x2", "the older frozen replay of the condition must not follow its newer event");
+ }
+
+ /// #854 review: the custom Server-object refresh is refused once the node manager is disposed, like the base's.
+ [Fact]
+ public async Task A_refresh_after_disposal_is_refused()
+ {
+ var ct = TestContext.Current.CancellationToken;
+ var rig = await ServerEventRig.StartAsync("Refresh854Dispose", encrypted: false, ct);
+ var nm = rig.Nm;
+ await rig.DisposeAsync();
+ nm.Dispose();
+ Should.Throw(() => nm.ConditionRefresh(null!, Array.Empty()));
+ }
+
///
/// The race the item gate closes, made deterministic: a deferred event is between its supersession check and its
/// queueing to the Server-object item when the refresh arrives. The refresh must wait for that one delivery (so
@@ -294,6 +450,7 @@ public sealed class ConditionRefreshDeferralWireTests
}
}, stop.Token, TaskCreationOptions.LongRunning, TaskScheduler.Default);
+ var refusedAsInProgress = 0;
for (var r = 0; r < 40; r++)
{
var call = r % 3 == 2
@@ -301,7 +458,17 @@ public sealed class ConditionRefreshDeferralWireTests
serverSubscription.Id, onServer.Status.Id)
: serverSession.CallAsync(ObjectTypeIds.ConditionType, MethodIds.ConditionType_ConditionRefresh, ct,
serverSubscription.Id);
- await call.WaitAsync(TimeSpan.FromSeconds(20), ct);
+ try
+ {
+ await call.WaitAsync(TimeSpan.FromSeconds(20), ct);
+ }
+ catch (ServiceResultException ex) when (ex.StatusCode == StatusCodes.BadRefreshInProgress)
+ {
+ // The SDK answers the Call before the refresh body runs, so under load the previous refresh of this
+ // subscription may still be in progress; the SDK refuses the overlap (its rule, not ours).
+ refusedAsInProgress++;
+ }
+
await Task.Delay(TimeSpan.FromMilliseconds(80), ct);
}
@@ -311,16 +478,17 @@ public sealed class ConditionRefreshDeferralWireTests
Volatile.Read(ref deferredSeen).ShouldBeGreaterThan(1, "the stress must actually have run with deferred events");
await RecordedEvents.WaitUntilAsync(() => rig.Nm.DeferredEventReports == 0);
- var last = $"s{Volatile.Read(ref counter)}";
+ var newest = $"s{Volatile.Read(ref counter)}";
await folderSubscription.SetPublishingModeAsync(true, ct);
- await RecordedEvents.WaitUntilAsync(() => serverEvents.Has(onServer, last));
+ await RecordedEvents.WaitUntilAsync(() => serverEvents.Has(onServer, newest));
await Task.Delay(TimeSpan.FromMilliseconds(500), ct);
- // Walk the Server-object stream: after each RefreshEnd, a condition event must not be older than what that
- // refresh replayed (the refresh replays the then-current state, so the floor is its replayed counter).
- var floor = -1;
+ // Walk the Server-object stream (one condition). Outside a refresh its states never go backwards; and each refresh
+ // ends on the newest state the item has seen — its replay is never older than an event already delivered, and
+ // nothing older than it follows RefreshEnd.
+ var max = -1;
+ var last = -1;
var replaying = false;
- var replayedInThisRefresh = -1;
var violations = new List();
foreach (var f in serverEvents.Of(onServer))
{
@@ -328,33 +496,139 @@ public sealed class ConditionRefreshDeferralWireTests
if (type == ObjectTypeIds.RefreshStartEventType)
{
replaying = true;
- replayedInThisRefresh = -1;
continue;
}
if (type == ObjectTypeIds.RefreshEndEventType)
{
replaying = false;
- floor = Math.Max(floor, replayedInThisRefresh);
+ if (last < max) violations.Add($"a refresh ended on s{last} after s{max} had been delivered");
continue;
}
if (!f[RecordedEvents.AckedField].TryGetValue(out bool _)) continue;
var n = int.Parse(RecordedEvents.Message(f)![1..], System.Globalization.CultureInfo.InvariantCulture);
- if (replaying)
- {
- replayedInThisRefresh = n;
- continue;
- }
-
- if (n < floor) violations.Add($"s{n} after a refresh that replayed s{floor}");
+ if (!replaying && n < max) violations.Add($"s{n} delivered after s{max}");
+ max = Math.Max(max, n);
+ last = n;
}
violations.ShouldBeEmpty();
+ refusedAsInProgress.ShouldBeLessThan(40, "most refreshes must actually have run");
rig.Nm.RefreshSupersededDeliveries.ShouldBeGreaterThan(0, "some refresh must actually have overtaken deferred events");
RecordedEvents.Message(serverEvents.Of(onServer).Last(f => f[RecordedEvents.AckedField].TryGetValue(out bool _)))
- .ShouldBe(last, "the stream still converges on the newest state");
- await RecordedEvents.WaitUntilAsync(() => folderEvents.Has(onA, last));
+ .ShouldBe(newest, "the stream still converges on the newest state");
+ await RecordedEvents.WaitUntilAsync(() => folderEvents.Has(onA, newest));
+ }
+
+ ///
+ /// Review of 1622d07f: a Server-object refresh must not hold the node manager's Lock across a walk of a large
+ /// address space — ScadaBridge refreshes on every reconnect, and any session may loop ConditionRefresh. Measures
+ /// the longest any other thread waits for Lock while a refresh of 3000 retained conditions runs, with
+ /// nothing deferred (the common case) and with a deferral in progress, and pins that the common case does not
+ /// build or queue its replay under Lock.
+ ///
+ /// Whether a deferral episode is in progress when the refresh runs.
+ [Theory]
+ [InlineData(false)]
+ [InlineData(true)]
+ public async Task A_refresh_of_a_large_address_space_keeps_the_node_manager_lock_hold_short(bool deferring)
+ {
+ const int Conditions = 3000;
+ var ct = TestContext.Current.CancellationToken;
+ await using var rig = await ServerEventRig.StartAsync("Refresh854Lock", encrypted: false, ct);
+ rig.KeyRoles = [];
+ rig.MaterialiseNative();
+ rig.Enforce(false, [ServerEventRig.Key()], KeyEquipmentGrant(EqA));
+ for (var i = 0; i < Conditions; i++)
+ {
+ var id = $"{ServerEventRig.RawDeviceFolder}/c{i}";
+ rig.Sink.MaterialiseAlarmCondition(id, ServerEventRig.RawDeviceFolder, $"c{i}", "OffNormalAlarm", 700, AddressSpaceRealm.Raw, isNative: true);
+ rig.Sink.WriteAlarmCondition(id, Active($"c{i}"), DateTime.UtcNow, AddressSpaceRealm.Raw);
+ }
+
+ using var folderSession = await rig.ConnectAsync(anonymous: false, ct);
+ var folderEvents = new RecordedEvents();
+ var folderSubscription = await RecordedEvents.SubscribeAsync(folderSession, folderEvents, ct);
+ var onA = RecordedEvents.AddEventItem(folderSubscription, ServerEventRig.UnsNodeId(folderSession, EqA));
+ await folderSubscription.ApplyChangesAsync(ct);
+
+ using var serverSession = await rig.ConnectAsync(anonymous: false, ct);
+ var serverEvents = new RecordedEvents();
+ var serverSubscription = await RecordedEvents.SubscribeAsync(serverSession, serverEvents, ct);
+ var onServer = RecordedEvents.AddEventItem(serverSubscription, ObjectIds.Server);
+ onServer.QueueSize = 10_000;
+ await serverSubscription.ApplyChangesAsync(ct);
+
+ rig.Project(native: true, Active("seed"));
+ await RecordedEvents.WaitUntilAsync(() => folderEvents.Has(onA, "seed") && serverEvents.Has(onServer, "seed"));
+ await folderSubscription.SetPublishingModeAsync(false, ct);
+
+ var stall = deferring ? ItemLockStall.Hold(FindServerItem(rig.Nm, onA.Status.Id)) : null;
+ try
+ {
+ if (deferring)
+ {
+ for (var i = 0; i < FloodSize; i++) rig.Project(native: true, Active($"f{i}"));
+ rig.Nm.DeferredEventReports.ShouldBeGreaterThan(0);
+ }
+
+ var probes = new System.Collections.Concurrent.ConcurrentQueue<(bool Cut, bool LockHeld)>();
+ rig.Nm.ServerObjectRefreshProbe = (cut, held) => probes.Enqueue((cut, held));
+ var waits = new List();
+ for (var round = 0; round < 5; round++)
+ {
+ var ends = serverEvents.Of(onServer).Count(f => f[RecordedEvents.EventTypeField].GetNodeId() == ObjectTypeIds.RefreshEndEventType);
+ using var stop = new CancellationTokenSource();
+ var maxWait = 0.0;
+ var prober = Task.Factory.StartNew(() =>
+ {
+ var sw = new Stopwatch();
+ while (!stop.IsCancellationRequested)
+ {
+ sw.Restart();
+ lock (rig.Nm.Lock) { }
+ maxWait = Math.Max(maxWait, sw.Elapsed.TotalMilliseconds);
+ Thread.Yield();
+ }
+ }, CancellationToken.None, TaskCreationOptions.LongRunning, TaskScheduler.Default);
+
+ await serverSession.CallAsync(
+ ObjectTypeIds.ConditionType, MethodIds.ConditionType_ConditionRefresh, ct, serverSubscription.Id);
+ await RecordedEvents.WaitUntilAsync(() => serverEvents.Of(onServer)
+ .Count(f => f[RecordedEvents.EventTypeField].GetNodeId() == ObjectTypeIds.RefreshEndEventType) > ends);
+ await stop.CancelAsync();
+ await prober;
+ waits.Add(maxWait);
+ }
+
+ TestContext.Current.TestOutputHelper?.WriteLine(
+ $"#854 lock-hold deferring={deferring} conditions={Conditions}: max Lock wait per refresh (ms) = "
+ + string.Join(", ", waits.Select(w => w.ToString("F1", System.Globalization.CultureInfo.InvariantCulture))));
+ // Neither path queues its replay under Lock; only a deferral makes a refresh take the cut path.
+ probes.ShouldNotBeEmpty();
+ probes.ShouldAllBe(p => !p.LockHeld);
+ if (deferring) probes.ShouldContain(p => p.Cut);
+ else probes.ShouldAllBe(p => !p.Cut);
+ }
+ finally
+ {
+ stall?.Dispose();
+ }
+ }
+
+ /// The server-side Server-object (all-events) item behind a client item.
+ private static IEventMonitoredItem FindAllEventsItem(OtOpcUaNodeManager nm, uint id)
+ {
+ var map = (IDictionary)typeof(OtOpcUaNodeManager)
+ .GetField("_allEventsItems", BindingFlags.Instance | BindingFlags.NonPublic)!
+ .GetValue(nm)!;
+ foreach (var key in map.Keys)
+ {
+ if (key is IEventMonitoredItem item && item.Id == id) return item;
+ }
+
+ throw new InvalidOperationException($"no server-side all-events item {id}");
}
/// The server-side event item behind a client item, from the node manager's direct-item map.