* Removed Heartbeat timer

* Implemented a proper update thread
* Removed the UpdateLock Mutex as it's no longer needed because updates can only happen one at a time now.
* This should actually improve performance significantly.. But, see the warning on the next line!
* Warning: If there are deadlocks that the threadpool timer method was hiding, this will expose them for all the nastiness they are.

OpenSim/Region/Environment/Scenes/Scene.cs

@@ -61,9 +61,10 @@ namespace OpenSim.Region.Environment.Scenes
         public SynchronizeSceneHandler SynchronizeScene = null;
         public int splitID = 0;
        
+
         #region Fields
 
-        protected Timer m_heartbeatTimer = new Timer();
+        
         protected Timer m_restartWaitTimer = new Timer();
 
         protected SimStatsReporter m_statsReporter;
@@ -83,7 +84,7 @@ namespace OpenSim.Region.Environment.Scenes
 
         private int m_timePhase = 24;
 
-        private readonly Mutex updateLock;
+        
 
         /// <summary>
         /// Are we applying physics to any of the prims in this scene?
@@ -169,6 +170,8 @@ namespace OpenSim.Region.Environment.Scenes
         private bool m_scripts_enabled = true;
         private string m_defaultScriptEngine;
         private int m_LastLogin = 0;
+        private Thread HeartbeatThread;
+        private volatile bool shuttingdown = false;
 
         #endregion
 
@@ -259,7 +262,7 @@ namespace OpenSim.Region.Environment.Scenes
                      bool SeeIntoRegionFromNeighbor, IConfigSource config, string simulatorVersion)
         {
             m_config = config;
-            updateLock = new Mutex(false);
+            
             m_moduleLoader = moduleLoader;
             m_authenticateHandler = authen;
             CommsManager = commsMan;
@@ -631,7 +634,8 @@ namespace OpenSim.Region.Environment.Scenes
             // Stop all client threads.
             ForEachScenePresence(delegate(ScenePresence avatar) { avatar.ControllingClient.Close(true); });
             // Stop updating the scene objects and agents.
-            m_heartbeatTimer.Close();
+            //m_heartbeatTimer.Close();
+            shuttingdown = true;
             // close the inner scene
             m_innerScene.Close();
             // De-register with region communications (events cleanup)
@@ -656,10 +660,16 @@ namespace OpenSim.Region.Environment.Scenes
         /// </summary>
         public void StartTimer()
         {
-            m_log.Debug("[SCENE]: Starting timer");
-            m_heartbeatTimer.Enabled = true;
-            m_heartbeatTimer.Interval = (int)(m_timespan * 1000);
-            m_heartbeatTimer.Elapsed += new ElapsedEventHandler(Heartbeat);
+            //m_log.Debug("[SCENE]: Starting timer");
+            //m_heartbeatTimer.Enabled = true;
+            //m_heartbeatTimer.Interval = (int)(m_timespan * 1000);
+            //m_heartbeatTimer.Elapsed += new ElapsedEventHandler(Heartbeat);
+            HeartbeatThread = new Thread(new ParameterizedThreadStart(Heartbeat));
+            HeartbeatThread.SetApartmentState(ApartmentState.MTA);
+            HeartbeatThread.Name = "Heartbeat";
+            HeartbeatThread.Priority = ThreadPriority.AboveNormal;
+            ThreadTracker.Add(HeartbeatThread);
+            HeartbeatThread.Start();
         }
 
         /// <summary>
@@ -685,7 +695,7 @@ namespace OpenSim.Region.Environment.Scenes
         /// </summary>
         /// <param name="sender"></param>
         /// <param name="e"></param>
-        private void Heartbeat(object sender, EventArgs e)
+        private void Heartbeat(object sender)
         {
             Update();
         }
@@ -695,9 +705,14 @@ namespace OpenSim.Region.Environment.Scenes
         /// </summary>
         public override void Update()
         {
+            int maintc = 0;
+            while (!shuttingdown)
+            {
+                maintc = System.Environment.TickCount;
+
                 TimeSpan SinceLastFrame = DateTime.Now - m_lastupdate;
                 // Aquire a lock so only one update call happens at once
-            updateLock.WaitOne();
+                //updateLock.WaitOne();
                 float physicsFPS = 0;
                 //m_log.Info("sadfadf" + m_neighbours.Count.ToString());
                 int agentsInScene = m_innerScene.GetRootAgentCount() + m_innerScene.GetChildAgentCount();
@@ -822,7 +837,7 @@ namespace OpenSim.Region.Environment.Scenes
                 }
                 finally
                 {
-                updateLock.ReleaseMutex();
+                    //updateLock.ReleaseMutex();
                     // Get actual time dilation
                     float tmpval = (m_timespan / (float)SinceLastFrame.TotalSeconds);
 
@@ -836,6 +851,12 @@ namespace OpenSim.Region.Environment.Scenes
 
                     m_lastupdate = DateTime.Now;
                 }
+                maintc = System.Environment.TickCount - maintc;
+                maintc = (int)(m_timespan * 1000) - maintc;
+                
+                if ((maintc < (m_timespan * 1000)) && maintc > 0)
+                    Thread.Sleep(maintc);
+            }
         }
 
         private void SendSimStatsPackets(SimStats stats)