Optimize trace detail page performance

src/Aspire.Dashboard/Components/Interactions/InteractionsProvider.cs

@@ -28,14 +28,14 @@ internal record InteractionMessageBarReference(int InteractionId, Message Messag
     {
         public void Dispose()
         {
-            TelemetryContext?.Dispose();
+            TelemetryContext.Dispose();
         }
     }
     internal record InteractionDialogReference(int InteractionId, IDialogReference Dialog, ComponentTelemetryContext TelemetryContext) : IDisposable
     {
         public void Dispose()
         {
-            TelemetryContext?.Dispose();
+            TelemetryContext.Dispose();
         }
     }
 

src/Aspire.Dashboard/Components/Pages/TraceDetail.razor.cs

@@ -261,9 +261,22 @@ private void UpdateSubscription()
             _tracesSubscription?.Dispose();
             _tracesSubscription = TelemetryRepository.OnNewTraces(_trace.FirstSpan.Source.ApplicationKey, SubscriptionType.Read, () => InvokeAsync(async () =>
             {
-                UpdateDetailViewData();
-                await InvokeAsync(StateHasChanged);
-                await _dataGrid.SafeRefreshDataAsync();
+                if (_trace == null)
+                {
+                    return;
+                }
+
+                // Only update trace if required.
+                if (TelemetryRepository.HasUpdatedTrace(_trace))
+                {
+                    UpdateDetailViewData();
+                    StateHasChanged();
+                    await _dataGrid.SafeRefreshDataAsync();
+                }
+                else
+                {
+                    Logger.LogTrace("Trace '{TraceId}' is unchanged.", TraceId);
+                }
             }));
         }
     }

src/Aspire.Dashboard/Otlp/Model/OtlpSpan.cs

@@ -42,12 +42,18 @@ public class OtlpSpan
     public OtlpScope Scope { get; }
     public TimeSpan Duration => EndTime - StartTime;
 
-    public OtlpApplication? UninstrumentedPeer { get; internal set; }
+    public OtlpApplication? UninstrumentedPeer { get => _uninstrumentedPeer; init => _uninstrumentedPeer = value; }
 
     public IEnumerable<OtlpSpan> GetChildSpans() => GetChildSpans(this, Trace.Spans);
     public static IEnumerable<OtlpSpan> GetChildSpans(OtlpSpan parentSpan, OtlpSpanCollection spans) => spans.Where(s => s.ParentSpanId == parentSpan.SpanId);
 
     private string? _cachedDisplaySummary;
+    private OtlpApplication? _uninstrumentedPeer;
+
+    public void SetUninstrumentedPeer(OtlpApplication? peer)
+    {
+        _uninstrumentedPeer = peer;
+    }
 
     public OtlpSpan? GetParentSpan()
     {

src/Aspire.Dashboard/Otlp/Model/OtlpTrace.cs

@@ -36,6 +36,7 @@ public TimeSpan Duration
     }
 
     public OtlpSpanCollection Spans { get; } = new OtlpSpanCollection();
+    public DateTime LastUpdatedDate { get; private set; }
 
     public int CalculateDepth(OtlpSpan span)
     {
@@ -51,7 +52,7 @@ public int CalculateDepth(OtlpSpan span)
 
     public int CalculateMaxDepth() => Spans.Max(CalculateDepth);
 
-    public void AddSpan(OtlpSpan span)
+    public void AddSpan(OtlpSpan span, bool skipLastUpdatedDate = false)
     {
         if (Spans.Contains(span.SpanId))
         {
@@ -99,6 +100,11 @@ public void AddSpan(OtlpSpan span)
             FullName = BuildFullName(span);
         }
 
+        if (!skipLastUpdatedDate)
+        {
+            LastUpdatedDate = DateTime.UtcNow;
+        }
+
         AssertSpanOrder();
 
         static string BuildFullName(OtlpSpan existingSpan)
@@ -148,19 +154,20 @@ private void AssertSpanOrder()
         }
     }
 
-    public OtlpTrace(ReadOnlyMemory<byte> traceId)
+    public OtlpTrace(ReadOnlyMemory<byte> traceId, DateTime lastUpdatedDate)
     {
         Key = traceId;
         TraceId = OtlpHelpers.ToHexString(traceId);
         FullName = string.Empty;
+        LastUpdatedDate = lastUpdatedDate;
     }
 
     public static OtlpTrace Clone(OtlpTrace trace)
     {
-        var newTrace = new OtlpTrace(trace.Key);
+        var newTrace = new OtlpTrace(trace.Key, trace.LastUpdatedDate);
         foreach (var item in trace.Spans)
         {
-            newTrace.AddSpan(OtlpSpan.Clone(item, newTrace));
+            newTrace.AddSpan(OtlpSpan.Clone(item, newTrace), skipLastUpdatedDate: true);
         }
 
         return newTrace;
@@ -171,6 +178,17 @@ private string DebuggerToString()
         return $@"TraceId = ""{TraceId}"", Spans = {Spans.Count}, StartDate = {FirstSpan?.StartTime.ToLocalTime():yyyy:MM:dd}, StartTime = {FirstSpan?.StartTime.ToLocalTime():h:mm:ss.fff tt}, Duration = {Duration}";
     }
 
+    public void SetSpanUninstrumentedPeer(OtlpSpan span, OtlpApplication? app)
+    {
+        if (span.Trace != this)
+        {
+            throw new ArgumentException("Span does not belong to this trace.", nameof(span));
+        }
+
+        span.SetUninstrumentedPeer(app);
+        LastUpdatedDate = DateTime.UtcNow;
+    }
+
     private sealed class SpanStartDateComparer : IComparer<OtlpSpan>
     {
         public static readonly SpanStartDateComparer Instance = new SpanStartDateComparer();

src/Aspire.Dashboard/Otlp/Storage/TelemetryRepository.cs

@@ -765,13 +765,34 @@ public Dictionary<string, int> GetLogsFieldValues(string attributeName)
         return attributesValues;
     }
 
+    public bool HasUpdatedTrace(OtlpTrace trace)
+    {
+        _tracesLock.EnterReadLock();
+
+        try
+        {
+            var latestTrace = GetTraceUnsynchronized(trace.TraceId);
+            if (latestTrace == null)
+            {
+                // Trace must have been removed. Technically there is an update (nothing).
+                return true;
+            }
+
+            return latestTrace.LastUpdatedDate > trace.LastUpdatedDate;
+        }
+        finally
+        {
+            _tracesLock.ExitReadLock();
+        }
+    }
+
     public OtlpTrace? GetTrace(string traceId)
     {
         _tracesLock.EnterReadLock();
 
         try
         {
-            return GetTraceUnsynchronized(traceId);
+            return GetTraceAndCloneUnsynchronized(traceId);
         }
         finally
         {
@@ -787,18 +808,28 @@ public Dictionary<string, int> GetLogsFieldValues(string attributeName)
         {
             if (OtlpHelpers.MatchTelemetryId(traceId, trace.TraceId))
             {
-                return OtlpTrace.Clone(trace);
+                return trace;
             }
         }
 
         return null;
     }
 
-    private OtlpSpan? GetSpanUnsynchronized(string traceId, string spanId)
+    private OtlpTrace? GetTraceAndCloneUnsynchronized(string traceId)
     {
-        Debug.Assert(_tracesLock.IsReadLockHeld || _tracesLock.IsWriteLockHeld, $"Must get lock before calling {nameof(GetSpanUnsynchronized)}.");
+        Debug.Assert(_tracesLock.IsReadLockHeld || _tracesLock.IsWriteLockHeld, $"Must get lock before calling {nameof(GetTraceAndCloneUnsynchronized)}.");
 
         var trace = GetTraceUnsynchronized(traceId);
+
+        return trace != null ? OtlpTrace.Clone(trace) : null;
+    }
+
+    private OtlpSpan? GetSpanAndCloneUnsynchronized(string traceId, string spanId)
+    {
+        Debug.Assert(_tracesLock.IsReadLockHeld || _tracesLock.IsWriteLockHeld, $"Must get lock before calling {nameof(GetSpanAndCloneUnsynchronized)}.");
+
+        // Trace and its spans are cloned here.
+        var trace = GetTraceAndCloneUnsynchronized(traceId);
         if (trace != null)
         {
             foreach (var span in trace.Spans)
@@ -819,7 +850,7 @@ public Dictionary<string, int> GetLogsFieldValues(string attributeName)
 
         try
         {
-            return GetSpanUnsynchronized(traceId, spanId);
+            return GetSpanAndCloneUnsynchronized(traceId, spanId);
         }
         finally
         {
@@ -938,7 +969,7 @@ internal void AddTracesCore(AddContext context, OtlpApplicationView applicationV
                         {
                             if (!TryGetTraceById(_traces, span.TraceId.Memory, out trace))
                             {
-                                trace = new OtlpTrace(span.TraceId.Memory);
+                                trace = new OtlpTrace(span.TraceId.Memory, DateTime.UtcNow);
                                 newTrace = true;
                             }
                         }
@@ -961,7 +992,7 @@ internal void AddTracesCore(AddContext context, OtlpApplicationView applicationV
                         {
                             _spanLinks.Add(link);
 
-                            var linkedSpan = GetSpanUnsynchronized(link.TraceId, link.SpanId);
+                            var linkedSpan = GetSpanAndCloneUnsynchronized(link.TraceId, link.SpanId);
                             linkedSpan?.BackLinks.Add(link);
                         }
 
@@ -1090,11 +1121,11 @@ private void CalculateTraceUninstrumentedPeers(OtlpTrace trace)
 
                 var appKey = ApplicationKey.Create(name: uninstrumentedPeer.DisplayName, instanceId: uninstrumentedPeer.Name);
                 var (app, _) = GetOrAddApplication(appKey, uninstrumentedPeer: true);
-                span.UninstrumentedPeer = app;
+                trace.SetSpanUninstrumentedPeer(span, app);
             }
             else
             {
-                span.UninstrumentedPeer = null;
+                trace.SetSpanUninstrumentedPeer(span, null);
             }
         }
     }