Mantis #2621: Thanks idb, for a patch that will persist regularily changed objects better.

Objects will be persisted now MinimumTimeBeforePersistenceConsidered seconds
after the last change, but latest MaximumTimeBeforePersistenceConsidered after
the first change (both are configurable in OpenSim.ini.example and are set to
60 and 600 as default).

3 files changed, 81 insertions, 18 deletions

diff --git a/OpenSim/Region/Environment/Scenes/Scene.cs b/OpenSim/Region/Environment/Scenes/Scene.cs
index f606018..eb9d509 100644
--- a/OpenSim/Region/Environment/Scenes/Scene.cs
+++ b/OpenSim/Region/Environment/Scenes/Scene.cs
@@ -62,6 +62,9 @@ namespace OpenSim.Region.Environment.Scenes
         public SynchronizeSceneHandler SynchronizeScene = null;
         public int splitID = 0;
 
+        private const long DEFAULT_MIN_TIME_FOR_PERSISTENCE = 60L;
+        private const long DEFAULT_MAX_TIME_FOR_PERSISTENCE = 600L;
+
         #region Fields
 
         protected Timer m_restartWaitTimer = new Timer();
@@ -171,6 +174,11 @@ namespace OpenSim.Region.Environment.Scenes
 
         private object m_deleting_scene_object = new object();
 
+        // the minimum time that must elapse before a changed object will be considered for persisted
+        public long m_dontPersistBefore = DEFAULT_MIN_TIME_FOR_PERSISTENCE * 10000000L;
+        // the maximum time that must elapse before a changed object will be considered for persisted
+        public long m_persistAfter = DEFAULT_MAX_TIME_FOR_PERSISTENCE * 10000000L;
+
         #endregion
 
         #region Properties
@@ -335,6 +343,12 @@ namespace OpenSim.Region.Environment.Scenes
                 m_maxNonphys = startupConfig.GetFloat("NonPhysicalPrimMax", 65536.0f);
                 m_maxPhys = startupConfig.GetFloat("PhysicalPrimMax", 10.0f);
                 m_clampPrimSize = startupConfig.GetBoolean("ClampPrimSize", false);
+                m_dontPersistBefore =
+                  startupConfig.GetInt("MinimumTimeBeforePersistenceConsidered", DEFAULT_MIN_TIME_FOR_PERSISTENCE);
+                m_dontPersistBefore *= 10000000;
+                m_persistAfter =
+                  startupConfig.GetInt("MaximumTimeBeforePersistenceConsidered", DEFAULT_MAX_TIME_FOR_PERSISTENCE);
+                m_persistAfter *= 10000000;
 
                 m_defaultScriptEngine = startupConfig.GetString("DefaultScriptEngine", "DotNetEngine");
             }
@@ -348,6 +362,11 @@ namespace OpenSim.Region.Environment.Scenes
 
         #region Startup / Close Methods
 
+        public bool ShuttingDown
+        {
+            get { return shuttingdown; }
+        }
+
         protected virtual void RegisterDefaultSceneEvents()
         {
             m_eventManager.OnPermissionError += SendPermissionAlert;
diff --git a/OpenSim/Region/Environment/Scenes/SceneObjectGroup.cs b/OpenSim/Region/Environment/Scenes/SceneObjectGroup.cs
index c51f235..d929be2 100644
--- a/OpenSim/Region/Environment/Scenes/SceneObjectGroup.cs
+++ b/OpenSim/Region/Environment/Scenes/SceneObjectGroup.cs
@@ -92,7 +92,39 @@ namespace OpenSim.Region.Environment.Scenes
         /// Signal whether the non-inventory attributes of any prims in the group have changed
         /// since the group's last persistent backup
         /// </summary>
-        public bool HasGroupChanged = false;
+        private bool m_hasGroupChanged = false;
+        private long timeFirstChanged;
+        private long timeLastChanged;
+
+        public bool HasGroupChanged
+        {
+            set
+            {
+                if (value)
+                {
+                    timeLastChanged = DateTime.Now.Ticks;
+                    if (!m_hasGroupChanged)
+                        timeFirstChanged = DateTime.Now.Ticks;
+                }
+                m_hasGroupChanged = value;
+            }
+
+            get { return m_hasGroupChanged; }
+        }
+
+        private bool isTimeToPersist()
+        {
+            if (IsSelected || IsDeleted || IsAttachment)
+                return false;
+            if (!m_hasGroupChanged)
+                return false;
+            if (m_scene.ShuttingDown)
+                return true;
+            long currentTime = DateTime.Now.Ticks;
+            if (currentTime - timeLastChanged > m_scene.m_dontPersistBefore || currentTime - timeFirstChanged > m_scene.m_persistAfter)
+                return true;
+            return false;
+        }
         
         /// <value>
         /// Is this scene object acting as an attachment?
@@ -1190,25 +1222,28 @@ namespace OpenSim.Region.Environment.Scenes
 
             try
             {
-                ILandObject parcel = m_scene.LandChannel.GetLandObject(
-                        m_rootPart.GroupPosition.X, m_rootPart.GroupPosition.Y);
-
-                if (parcel != null && parcel.landData != null &&
-                        parcel.landData.OtherCleanTime != 0)
+                if (!m_scene.ShuttingDown) // if shutting down then there will be nothing to handle the return so leave till next restart
                 {
-                    if (parcel.landData.OwnerID != OwnerID &&
-                            (parcel.landData.GroupID != GroupID ||
-                            parcel.landData.GroupID == UUID.Zero))
+                    ILandObject parcel = m_scene.LandChannel.GetLandObject(
+                            m_rootPart.GroupPosition.X, m_rootPart.GroupPosition.Y);
+
+                    if (parcel != null && parcel.landData != null &&
+                            parcel.landData.OtherCleanTime != 0)
                     {
-                        if ((DateTime.Now - RootPart.Rezzed).TotalMinutes >
-                                parcel.landData.OtherCleanTime)
+                        if (parcel.landData.OwnerID != OwnerID &&
+                                (parcel.landData.GroupID != GroupID ||
+                                parcel.landData.GroupID == UUID.Zero))
                         {
-                            m_log.InfoFormat("[SCENE] Returning object {0} due to parcel auto return", RootPart.UUID.ToString());
-                            m_scene.AddReturn(OwnerID, Name, AbsolutePosition);
-                            m_scene.DeRezObject(null, RootPart.LocalId,
-                                RootPart.GroupID, 9, UUID.Zero);
+                            if ((DateTime.Now - RootPart.Rezzed).TotalMinutes >
+                                    parcel.landData.OtherCleanTime)
+                            {
+                                m_log.InfoFormat("[SCENE] Returning object {0} due to parcel auto return", RootPart.UUID.ToString());
+                                m_scene.AddReturn(OwnerID, Name, AbsolutePosition);
+                                m_scene.DeRezObject(null, RootPart.LocalId,
+                                    RootPart.GroupID, 9, UUID.Zero);
 
-                            return;
+                                return;
+                            }
                         }
                     }
                 }
@@ -1216,7 +1251,7 @@ namespace OpenSim.Region.Environment.Scenes
                 if (HasGroupChanged)
                 {
                     // don't backup while it's selected or you're asking for changes mid stream.
-                    if (!(IsSelected || IsDeleted || IsAttachment))
+                    if (isTimeToPersist())
                     {
                         m_log.DebugFormat(
                             "[SCENE]: Storing {0}, {1} in {2}",
@@ -1227,9 +1262,9 @@ namespace OpenSim.Region.Environment.Scenes
                         backup_group.RootPart.Acceleration = RootPart.Acceleration;
                         backup_group.RootPart.AngularVelocity = RootPart.AngularVelocity;
                         backup_group.RootPart.ParticleSystem = RootPart.ParticleSystem;
+                        HasGroupChanged = false;
 
                         datastore.StoreObject(backup_group, m_scene.RegionInfo.RegionID);
-                        HasGroupChanged = false;
 
                         backup_group.ForEachPart(delegate(SceneObjectPart part) { part.ProcessInventoryBackup(datastore); });
 
diff --git a/bin/OpenSim.ini.example b/bin/OpenSim.ini.example
index 7b61790..1464bee 100644
--- a/bin/OpenSim.ini.example
+++ b/bin/OpenSim.ini.example
@@ -79,6 +79,15 @@
     asset_database = "local"
     ;asset_database = "grid"
 
+    ; Persistence of changed objects happens during regular sweeps. The following control that behaviour to
+    ; prevent frequently changing objects from heavily loading the region data store.
+    ; If both of these values are set to zero then persistence of all changed objects will happen on every sweep.
+    ; 
+    ; Objects will be considered for persistance in the next sweep when they have not changed for this number of seconds
+    MinimumTimeBeforePersistenceConsidered = 60
+    ; Objects will always be considered for persistance in the next sweep if the first change occurred this number of seconds ago
+    MaximumTimeBeforePersistenceConsidered = 600
+
     ; Should avatars in neighbor sims see objects in this sim?
     see_into_this_sim_from_neighbor = True