From 7156545fcaa632a104f09a9dcffda5238c3bf75c Mon Sep 17 00:00:00 2001
From: Diva Canto <diva@metaverseink.com>
Date: Sat, 18 Feb 2012 21:59:42 -0800
Subject: [PATCH] This should smooth movement in heteregeneous networks by a
 lot: cache the region by position instead of looking it up all the time --
 this was being done during the main update loop!

---
 .../Grid/RegionInfoCache.cs                   | 34 ++++++++++++++++++-
 .../Grid/RemoteGridServiceConnector.cs        |  8 ++++-
 2 files changed, 40 insertions(+), 2 deletions(-)

diff --git a/OpenSim/Region/CoreModules/ServiceConnectorsOut/Grid/RegionInfoCache.cs b/OpenSim/Region/CoreModules/ServiceConnectorsOut/Grid/RegionInfoCache.cs
index 786e0b5737..be8a9a2307 100644
--- a/OpenSim/Region/CoreModules/ServiceConnectorsOut/Grid/RegionInfoCache.cs
+++ b/OpenSim/Region/CoreModules/ServiceConnectorsOut/Grid/RegionInfoCache.cs
@@ -65,13 +65,26 @@ namespace OpenSim.Region.CoreModules.ServiceConnectorsOut.Grid
             }
         }
 
+        internal struct ScopedRegionPosition
+        {
+            public UUID m_scopeID;
+            public ulong m_regionHandle;
+            public ScopedRegionPosition(UUID scopeID, ulong handle)
+            {
+                m_scopeID = scopeID;
+                m_regionHandle = handle;
+            }
+        }
+
         private ExpiringCache<ScopedRegionUUID, GridRegion> m_UUIDCache;
         private ExpiringCache<ScopedRegionName, ScopedRegionUUID> m_NameCache;
+        private ExpiringCache<ScopedRegionPosition, GridRegion> m_PositionCache;
 
         public RegionInfoCache()
         {
             m_UUIDCache = new ExpiringCache<ScopedRegionUUID, GridRegion>();
-            m_NameCache = new ExpiringCache<ScopedRegionName, ScopedRegionUUID>(); 
+            m_NameCache = new ExpiringCache<ScopedRegionName, ScopedRegionUUID>();
+            m_PositionCache = new ExpiringCache<ScopedRegionPosition, GridRegion>();
         }
 
         public void Cache(GridRegion rinfo)
@@ -96,6 +109,9 @@ namespace OpenSim.Region.CoreModules.ServiceConnectorsOut.Grid
             {
                 ScopedRegionName name = new ScopedRegionName(scopeID,rinfo.RegionName);
                 m_NameCache.AddOrUpdate(name, id, CACHE_EXPIRATION_SECONDS);
+
+                ScopedRegionPosition pos = new ScopedRegionPosition(scopeID, rinfo.RegionHandle);
+                m_PositionCache.AddOrUpdate(pos, rinfo, CACHE_EXPIRATION_SECONDS);
             }
         }
 
@@ -114,6 +130,22 @@ namespace OpenSim.Region.CoreModules.ServiceConnectorsOut.Grid
             return null;
         }
 
+        public GridRegion Get(UUID scopeID, ulong handle, out bool inCache)
+        {
+            inCache = false;
+
+            GridRegion rinfo = null;
+            ScopedRegionPosition pos = new ScopedRegionPosition(scopeID, handle);
+            if (m_PositionCache.TryGetValue(pos, out rinfo))
+            {
+                inCache = true;
+                return rinfo;
+            }
+
+            return null;
+        }
+
+
         public GridRegion Get(UUID scopeID, string name, out bool inCache)
         {
             inCache = false;
diff --git a/OpenSim/Region/CoreModules/ServiceConnectorsOut/Grid/RemoteGridServiceConnector.cs b/OpenSim/Region/CoreModules/ServiceConnectorsOut/Grid/RemoteGridServiceConnector.cs
index 6f364ae4c8..e6c89d7af6 100644
--- a/OpenSim/Region/CoreModules/ServiceConnectorsOut/Grid/RemoteGridServiceConnector.cs
+++ b/OpenSim/Region/CoreModules/ServiceConnectorsOut/Grid/RemoteGridServiceConnector.cs
@@ -186,10 +186,16 @@ namespace OpenSim.Region.CoreModules.ServiceConnectorsOut.Grid
 
         public GridRegion GetRegionByPosition(UUID scopeID, int x, int y)
         {
-            GridRegion rinfo = m_LocalGridService.GetRegionByPosition(scopeID, x, y);
+            bool inCache = false;
+            GridRegion rinfo = m_RegionInfoCache.Get(scopeID, Util.UIntsToLong((uint)x, (uint)y), out inCache);
+            if (inCache)
+                return rinfo;
+
+            rinfo = m_LocalGridService.GetRegionByPosition(scopeID, x, y);
             if (rinfo == null)
                 rinfo = m_RemoteGridService.GetRegionByPosition(scopeID, x, y);
 
+            m_RegionInfoCache.Cache(rinfo);
             return rinfo;
         }