diff --git a/pkg/dds/lib/src/isolate_manager.dart b/pkg/dds/lib/src/isolate_manager.dart
index 6ebfafaa94a..ddee5f959a8 100644
--- a/pkg/dds/lib/src/isolate_manager.dart
+++ b/pkg/dds/lib/src/isolate_manager.dart
@@ -346,13 +346,17 @@ class IsolateManager {
     final combinedBytes = base64Decode(timelineResult['trace']).toList();
 
     for (final isolateId in isolates.keys) {
-      final samplesResult =
-          await dds.vmServiceClient.sendRequest('getPerfettoCpuSamples', {
-        'isolateId': isolateId,
-        'timeOriginMicros': timeOriginMicros,
-        'timeExtentMicros': timeExtentMicros
-      });
-      combinedBytes.addAll(base64Decode(samplesResult['samples']));
+      try {
+        final samplesResult =
+            await dds.vmServiceClient.sendRequest('getPerfettoCpuSamples', {
+          'isolateId': isolateId,
+          'timeOriginMicros': timeOriginMicros,
+          'timeExtentMicros': timeExtentMicros
+        });
+        combinedBytes.addAll(base64Decode(samplesResult['samples']));
+      } on json_rpc.RpcException {
+        // The isolate may not yet be runnable.
+      }
     }
     timelineResult['trace'] = base64Encode(combinedBytes);
     return timelineResult;
diff --git a/pkg/dds/test/dap_handler_test.dart b/pkg/dds/test/dap_handler_test.dart
index b61235ffb31..f2a8d3684c9 100644
--- a/pkg/dds/test/dap_handler_test.dart
+++ b/pkg/dds/test/dap_handler_test.dart
@@ -116,8 +116,18 @@ void main() {
     );
     service = await vmServiceConnectUri(dds!.wsUri!.toString());
 
-    final isolate = (await service.getVM()).isolates!.first;
-    final isolateId = isolate.id!;
+    final isolateRef = (await service.getVM()).isolates!.first;
+    final isolateId = isolateRef.id!;
+
+    // Wait for the isolate to become runnable as `evaluateInFrame` requires
+    // the isolate to be runnable.
+    Isolate? isolate;
+    do {
+      if (isolate != null) {
+        await Future.delayed(const Duration(milliseconds: 50));
+      }
+      isolate = await service.getIsolate(isolateId);
+    } while (!isolate.runnable!);
 
     // Get the variable for 'myInstance'.
     final originalInstanceRef = (await service.evaluateInFrame(