add another kick to GC after map generation at run time

OpenSim/Region/Framework/Scenes/Scene.cs

@@ -31,6 +31,7 @@ using System.Diagnostics;
 using System.Drawing;
 using System.Drawing.Imaging;
 using System.IO;
+using System.Runtime;
 using System.Text;
 using System.Threading;
 using System.Timers;
@@ -6027,6 +6028,12 @@ Environment.Exit(1);
         {
             RegenerateMaptile();
 
+            GCSettings.LargeObjectHeapCompactionMode = GCLargeObjectHeapCompactionMode.CompactOnce;
+            GC.Collect();
+            GC.WaitForPendingFinalizers();
+            GC.Collect();
+            GCSettings.LargeObjectHeapCompactionMode = GCLargeObjectHeapCompactionMode.Default;
+
             // We need to propagate the new image UUID to the grid service
             // so that all simulators can retrieve it
             string error = GridService.RegisterRegion(RegionInfo.ScopeID, new GridRegion(RegionInfo));