diff --git a/TuneUp/ProfiledNodeViewModel.cs b/TuneUp/ProfiledNodeViewModel.cs
index 8c52c92..0647e8c 100644
--- a/TuneUp/ProfiledNodeViewModel.cs
+++ b/TuneUp/ProfiledNodeViewModel.cs
@@ -1,9 +1,11 @@
 using System;
 using System.ComponentModel.DataAnnotations;
+using System.Diagnostics;
 using System.Linq;
 using System.Reflection;
 using Dynamo.Core;
 using Dynamo.Graph.Nodes;
+
 namespace TuneUp
 {
     public class ProfiledNodeViewModel : NotificationObject
@@ -130,6 +132,11 @@ public string StateDescription
             }
         }
 
+        /// <summary>
+        /// The Stopwatch to measure execution time of this node
+        /// </summary>
+        internal Stopwatch Stopwatch { get; set; }
+
         internal NodeModel NodeModel { get; set; }
 
         #endregion
@@ -142,6 +149,7 @@ public ProfiledNodeViewModel(NodeModel node)
         {
             NodeModel = node;
             State = ProfiledNodeState.NotExecuted;
+            Stopwatch = new Stopwatch();
         }
 
         /// <summary>
diff --git a/TuneUp/TuneUpViewExtension.cs b/TuneUp/TuneUpViewExtension.cs
index 47c9f67..57fe602 100644
--- a/TuneUp/TuneUpViewExtension.cs
+++ b/TuneUp/TuneUpViewExtension.cs
@@ -1,4 +1,5 @@
-using System.Linq;
+using System;
+using System.Linq;
 using System.Windows.Controls;
 using Dynamo.Wpf.Extensions;
 
@@ -45,11 +46,12 @@ public override void Loaded(ViewLoadedParams p)
                 {
                     p.AddToExtensionsSideBar(this, TuneUpView);
                     ViewModel.SwitchToManualMode();
-                    ViewModel.EnableProfiling();                    
+                    ViewModel.EnableProfiling();
                 }
                 else
                 {
                     p.CloseExtensioninInSideBar(this);
+                    ViewModel.DisableProfiling();
                 }
             };
 
@@ -110,6 +112,10 @@ public override void Closed()
             if (this.TuneUpMenuItem != null)
             {
                 this.TuneUpMenuItem.IsChecked = false;
+
+                // Reset DataGrid sorting order & direction
+                ViewModel.SortingOrder = "number";
+                ViewModel.SortDirection = System.ComponentModel.ListSortDirection.Ascending;
             }
         }
     }
diff --git a/TuneUp/TuneUpWindow.xaml.cs b/TuneUp/TuneUpWindow.xaml.cs
index 1fd729e..839e7e2 100644
--- a/TuneUp/TuneUpWindow.xaml.cs
+++ b/TuneUp/TuneUpWindow.xaml.cs
@@ -1,4 +1,5 @@
-using System.Collections.Generic;
+using System;
+using System.Collections.Generic;
 using System.ComponentModel;
 using System.Linq;
 using System.Windows;
diff --git a/TuneUp/TuneUpWindowViewModel.cs b/TuneUp/TuneUpWindowViewModel.cs
index 5a4ace5..b65eaf0 100644
--- a/TuneUp/TuneUpWindowViewModel.cs
+++ b/TuneUp/TuneUpWindowViewModel.cs
@@ -61,7 +61,6 @@ public class TuneUpWindowViewModel : NotificationObject, IDisposable
         private ListSortDirection sortDirection;
         private string sortingOrder;
 
-
         /// <summary>
         /// Name of the row to display current execution time
         /// </summary>
@@ -213,6 +212,7 @@ public string TotalGraphExecutiontime
                 return (PreviousExecutionTimeRow?.ExecutionMilliseconds + CurrentExecutionTimeRow?.ExecutionMilliseconds).ToString() + "ms";
             }
         }
+
         #endregion
 
         #region Constructor
@@ -230,6 +230,7 @@ public TuneUpWindowViewModel(ViewLoadedParams p)
                 CurrentWorkspace = p.CurrentWorkspaceModel as HomeWorkspaceModel;
             }
         }
+
         #endregion
 
         #region ProfilingMethods
@@ -240,12 +241,16 @@ public TuneUpWindowViewModel(ViewLoadedParams p)
         /// </summary>
         internal void ResetProfiledNodes()
         {
-            if (CurrentWorkspace == null)
-            {
-                return;
-            }
-            nodeDictionary.Clear();
-            ProfiledNodes.Clear();
+            if (CurrentWorkspace == null) return;
+
+            // Use temporary collections to minimize UI updates
+            var newProfiledNodes = new ObservableCollection<ProfiledNodeViewModel>();
+            var newNodeDictionary = new Dictionary<Guid, ProfiledNodeViewModel>();
+
+            // Assign the new collection
+            ProfiledNodes = newProfiledNodes;
+            nodeDictionary = newNodeDictionary;
+
             foreach (var node in CurrentWorkspace.Nodes)
             {
                 var profiledNode = new ProfiledNodeViewModel(node);
@@ -309,6 +314,15 @@ internal void EnableProfiling()
             RaisePropertyChanged(nameof(ProfiledNodesCollection));
         }
 
+        internal void DisableProfiling()
+        {
+            if (isProfilingEnabled && CurrentWorkspace != null)
+            {
+                CurrentWorkspace.EngineController.EnableProfiling(false, CurrentWorkspace, CurrentWorkspace.Nodes);
+                isProfilingEnabled = false;
+            }
+        }
+
         #endregion
 
         #region ExecutionEvents
@@ -339,7 +353,7 @@ private void CurrentWorkspaceModel_EvaluationCompleted(object sender, Dynamo.Mod
             RaisePropertyChanged(nameof(ProfiledNodesCollection));
             RaisePropertyChanged(nameof(ProfiledNodes));
 
-            ProfiledNodesCollection.Dispatcher.Invoke(() =>
+            ProfiledNodesCollection.Dispatcher.InvokeAsync(() =>
             {
                 ApplySorting();
                 ProfiledNodesCollection.View.Refresh();
@@ -392,28 +406,29 @@ public void ApplySorting()
         internal void OnNodeExecutionBegin(NodeModel nm)
         {
             var profiledNode = nodeDictionary[nm.GUID];
+            profiledNode.Stopwatch.Start();
             profiledNode.State = ProfiledNodeState.Executing;
-            RaisePropertyChanged(nameof(ProfiledNodesCollection));
         }
 
         internal void OnNodeExecutionEnd(NodeModel nm)
         {
             var profiledNode = nodeDictionary[nm.GUID];
-            if (executionTimeData != null)
+            profiledNode.Stopwatch.Stop();
+            var executionTime = profiledNode.Stopwatch.Elapsed;
+
+            if (executionTime > TimeSpan.Zero)
             {
-                var executionTime = executionTimeData.NodeExecutionTime(nm);
-                if (executionTime != null)
-                {
-                    profiledNode.ExecutionTime = (TimeSpan)executionTime;
-                }
+                profiledNode.ExecutionTime = executionTime;
+
                 if (!profiledNode.WasExecutedOnLastRun)
                 {
                     profiledNode.ExecutionOrderNumber = executedNodesNum++;
                 }
             }
+
+            profiledNode.Stopwatch.Reset();
             profiledNode.WasExecutedOnLastRun = true;
             profiledNode.State = ProfiledNodeState.ExecutedOnCurrentRun;
-            RaisePropertyChanged(nameof(ProfiledNodesCollection));
         }
 
         #endregion
@@ -481,7 +496,7 @@ private void ManageWorkspaceEvents(HomeWorkspaceModel workspace, bool subscribe)
                     node.NodeExecutionBegin += OnNodeExecutionBegin;
                     node.NodeExecutionEnd += OnNodeExecutionEnd;
                 }
-                ResetProfiledNodes();                
+                ResetProfiledNodes();
             }
             // Unsubscribe to workspace events
             else
@@ -496,7 +511,7 @@ private void ManageWorkspaceEvents(HomeWorkspaceModel workspace, bool subscribe)
                     node.NodeExecutionBegin -= OnNodeExecutionBegin;
                     node.NodeExecutionEnd -= OnNodeExecutionEnd;
                 }
-            }            
+            }
             executedNodesNum = 0;
         }
 
@@ -539,4 +554,4 @@ public void ExportToCsv()
 
         #endregion
     }
-}
+}
\ No newline at end of file