in RegionInfoCache, replace lib omv ExpireCaches by a single dedicated one

OpenSim/Region/CoreModules/ServiceConnectorsOut/Grid/RegionInfoCache.cs

@@ -26,6 +26,7 @@
  */
 using System;
 using System.Reflection;
+using System.Threading;
 using System.Collections.Generic;
 using OpenSim.Framework;
 using OpenSim.Services.Interfaces;
@@ -37,54 +38,17 @@ namespace OpenSim.Region.CoreModules.ServiceConnectorsOut.Grid
 {
     public class RegionInfoCache
     {
-        private const double CACHE_EXPIRATION_SECONDS = 300.0; // 5 minutes
+        private const double CACHE_EXPIRATION_SECONDS = 120; // 2 minutes  opensim regions change a lot
 
 //        private static readonly ILog m_log =
 //                LogManager.GetLogger(
 //                MethodBase.GetCurrentMethod().DeclaringType);
         
-        internal struct ScopedRegionUUID
+        private RegionsExpiringCache m_Cache;
-        {
-            public UUID m_scopeID;
-            public UUID m_regionID;
-            public ScopedRegionUUID(UUID scopeID, UUID regionID)
-            {
-                m_scopeID = scopeID;
-                m_regionID = regionID;
-            }
-        }
-            
-        internal struct ScopedRegionName
-        {
-            public UUID m_scopeID;
-            public string m_name;
-            public ScopedRegionName(UUID scopeID, string name)
-            {
-                m_scopeID = scopeID;
-                m_name = name;
-            }
-        }
-
-        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_Cache = new RegionsExpiringCache();
-            m_NameCache = new ExpiringCache<ScopedRegionName, ScopedRegionUUID>();
-            m_PositionCache = new ExpiringCache<ScopedRegionPosition, GridRegion>();
         }
 
         public void Cache(GridRegion rinfo)
@@ -101,18 +65,7 @@ namespace OpenSim.Region.CoreModules.ServiceConnectorsOut.Grid
             if (rinfo == null)
                 return;
             
-            ScopedRegionUUID id = new ScopedRegionUUID(scopeID,regionID);
+            m_Cache.AddOrUpdate(scopeID, rinfo, CACHE_EXPIRATION_SECONDS);
-            
-            // Cache even null accounts
-            m_UUIDCache.AddOrUpdate(id, rinfo, CACHE_EXPIRATION_SECONDS);
-            if (rinfo != null)
-            {
-                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);
-            }
         }
 
         public GridRegion Get(UUID scopeID, UUID regionID, out bool inCache)
@@ -120,8 +73,7 @@ namespace OpenSim.Region.CoreModules.ServiceConnectorsOut.Grid
             inCache = false;
 
             GridRegion rinfo = null;
-            ScopedRegionUUID id = new ScopedRegionUUID(scopeID,regionID);
+            if (m_Cache.TryGetValue(scopeID, regionID, out rinfo))
-            if (m_UUIDCache.TryGetValue(id, out rinfo))
             {
                 inCache = true;
                 return rinfo;
@@ -135,8 +87,7 @@ namespace OpenSim.Region.CoreModules.ServiceConnectorsOut.Grid
             inCache = false;
 
             GridRegion rinfo = null;
-            ScopedRegionPosition pos = new ScopedRegionPosition(scopeID, handle);
+            if (m_Cache.TryGetValue(scopeID, handle, out rinfo))
-            if (m_PositionCache.TryGetValue(pos, out rinfo))
             {
                 inCache = true;
                 return rinfo;
@@ -145,25 +96,450 @@ namespace OpenSim.Region.CoreModules.ServiceConnectorsOut.Grid
             return null;
         }
 
-
         public GridRegion Get(UUID scopeID, string name, out bool inCache)
         {
             inCache = false;
 
-            ScopedRegionName sname = new ScopedRegionName(scopeID,name);
+            GridRegion rinfo = null;
-
+            if (m_Cache.TryGetValue(scopeID, name, out rinfo))
-            ScopedRegionUUID id;
-            if (m_NameCache.TryGetValue(sname, out id))
             {
-                GridRegion rinfo = null;
+                inCache = true;
-                if (m_UUIDCache.TryGetValue(id, out rinfo))
+                return rinfo;
-                {
-                    inCache = true;
-                    return rinfo;
-                }
             }
             
             return null;
         }
     }
+
+
+    // following code partialy adapted from lib OpenMetaverse
+    public class RegionKey : IComparable<RegionKey>
+    {
+        private UUID m_scopeID;
+        private UUID m_RegionID;
+        private DateTime m_expirationDate;
+
+        public RegionKey(UUID scopeID, UUID id)
+        {
+            m_scopeID = scopeID;
+            m_RegionID = id;
+        }
+
+        public UUID ScopeID
+        {
+            get { return m_scopeID; }
+        }
+        public DateTime ExpirationDate
+        {
+            get { return m_expirationDate; }
+            set { m_expirationDate = value; }
+        }
+
+        public int GetHaskCode()
+        {
+            int hash = m_scopeID.GetHashCode();
+            hash += hash * 23 + m_RegionID.GetHashCode();
+            return hash;
+        }
+
+        public int CompareTo(RegionKey other)
+        {
+            return GetHashCode().CompareTo(other.GetHashCode());
+        }
+    }
+
+    public class RegionInfoByScope
+    {
+        private Dictionary<string, RegionKey> byname;
+        private Dictionary<ulong, RegionKey> byhandle;
+
+        public RegionInfoByScope()
+        {
+            byname = new Dictionary<string, RegionKey>();
+            byhandle = new Dictionary<ulong, RegionKey>();
+        }
+
+        public RegionInfoByScope(GridRegion region, RegionKey key)
+        {
+           byname = new Dictionary<string, RegionKey>();
+           byhandle = new Dictionary<ulong, RegionKey>();
+
+           byname[region.RegionName] = key;
+           byhandle[region.RegionHandle] = key;
+        }
+
+        public void AddRegion(GridRegion region, RegionKey key)
+        {
+            if(byname == null)
+                byname = new Dictionary<string, RegionKey>();
+            if(byhandle == null)
+                byhandle = new Dictionary<ulong, RegionKey>();
+
+           byname[region.RegionName] = key;
+           byhandle[region.RegionHandle] = key;
+        }
+
+        public void RemoveRegion(GridRegion region)
+        {
+            if(byname != null)
+                byname.Remove(region.RegionName);
+            if(byhandle != null)
+                byhandle.Remove(region.RegionHandle);
+        }
+
+        public void Clear()
+        {
+            if(byname != null)
+                byname.Clear();
+            if(byhandle != null)
+                byhandle.Clear();
+            byname = null;
+            byhandle = null;
+        }
+
+        public RegionKey get(string name)
+        {
+            if(byname == null || !byname.ContainsKey(name))
+                return null;
+            return byname[name];
+        }
+
+        public RegionKey get(ulong handle)
+        {
+            if(byhandle == null || !byhandle.ContainsKey(handle))
+                return null;
+            return byhandle[handle];
+        }
+
+        public int Count()
+        {
+            if(byname == null)
+                return 0;
+            else
+                return byname.Count;
+        }
+    }
+  
+    public sealed class RegionsExpiringCache
+    {
+        const double CACHE_PURGE_HZ = 60;
+        const int MAX_LOCK_WAIT = 5000; // milliseconds
+ 
+        /// <summary>For thread safety</summary>
+        object syncRoot = new object();
+        /// <summary>For thread safety</summary>
+        object isPurging = new object();
+
+        Dictionary<RegionKey, GridRegion> timedStorage = new Dictionary<RegionKey, GridRegion>();
+        Dictionary<UUID, RegionInfoByScope> InfobyScope = new Dictionary<UUID, RegionInfoByScope>();
+        private System.Timers.Timer timer = new System.Timers.Timer(TimeSpan.FromSeconds(CACHE_PURGE_HZ).TotalMilliseconds);
+
+        public RegionsExpiringCache()
+        {
+            timer.Elapsed += PurgeCache;
+            timer.Start();
+        }
+
+        public bool Add(UUID scope, GridRegion region, double expirationSeconds)
+        {
+            if (!Monitor.TryEnter(syncRoot, MAX_LOCK_WAIT))
+                throw new ApplicationException("Lock could not be acquired after " + MAX_LOCK_WAIT + "ms");
+
+            RegionKey key = new RegionKey(scope , region.RegionID);
+         
+            try
+            {
+                if (timedStorage.ContainsKey(key))
+                    return false;
+
+                key.ExpirationDate = DateTime.UtcNow + TimeSpan.FromSeconds(expirationSeconds);
+                timedStorage.Add(key, region);
+
+                RegionInfoByScope ris = null;
+                if(!InfobyScope.TryGetValue(scope, out ris) || ris == null)
+                {
+                    ris = new RegionInfoByScope(region, key);
+                    InfobyScope[scope] = ris;
+                }
+                else 
+                    ris.AddRegion(region, key);
+
+                return true;
+            }
+            finally { Monitor.Exit(syncRoot);}
+        }
+
+        public bool AddOrUpdate(UUID scope, GridRegion region, double expirationSeconds)
+        {
+            if (!Monitor.TryEnter(syncRoot, MAX_LOCK_WAIT))
+                throw new ApplicationException("Lock could not be acquired after " + MAX_LOCK_WAIT + "ms");
+            
+            try
+            {
+                RegionKey key = new RegionKey(scope, region.RegionID);
+                key.ExpirationDate = DateTime.UtcNow + TimeSpan.FromSeconds(expirationSeconds);
+
+                if (timedStorage.ContainsKey(key))
+                {
+                    timedStorage.Remove(key);
+                    timedStorage.Add(key, region);
+
+                    if(!InfobyScope.ContainsKey(scope))
+                    {
+                        RegionInfoByScope ris = new RegionInfoByScope(region, key);
+                        InfobyScope[scope] = ris;
+                    }
+                    return false;
+                }
+                else
+                {
+                    timedStorage.Add(key, region);
+                    RegionInfoByScope ris = null;
+                    if(!InfobyScope.TryGetValue(scope, out ris) || ris == null)
+                    {
+                        ris = new RegionInfoByScope(region,key);
+                        InfobyScope[scope] = ris;
+                    }
+                    else 
+                        ris.AddRegion(region,key);
+                    return true;
+                }
+            }
+            finally { Monitor.Exit(syncRoot); }
+        }
+
+        public void Clear()
+        {
+            if (!Monitor.TryEnter(syncRoot, MAX_LOCK_WAIT))
+                throw new ApplicationException("Lock could not be acquired after " + MAX_LOCK_WAIT + "ms");
+            try
+            {
+                timedStorage.Clear();
+                InfobyScope.Clear();
+            }
+            finally { Monitor.Exit(syncRoot); }
+        }
+        
+        public bool Contains(UUID scope, GridRegion region)
+        {
+            RegionKey key = new RegionKey(scope, region.RegionID);
+            return Contains(key);
+        }
+
+        public bool Contains(RegionKey key)
+        {
+            if (!Monitor.TryEnter(syncRoot, MAX_LOCK_WAIT))
+                throw new ApplicationException("Lock could not be acquired after " + MAX_LOCK_WAIT + "ms");
+            try
+            {
+                return timedStorage.ContainsKey(key);
+            }
+            finally { Monitor.Exit(syncRoot); }
+        }
+
+        public int Count
+        {
+            get
+            {
+                return timedStorage.Count;
+            }
+        }
+
+        public bool Remove(UUID scope, GridRegion region)
+        {
+            RegionKey key = new RegionKey(scope, region.RegionID);
+
+            if (!Monitor.TryEnter(syncRoot, MAX_LOCK_WAIT))
+                throw new ApplicationException("Lock could not be acquired after " + MAX_LOCK_WAIT + "ms");
+            try
+            {               
+                if (timedStorage.ContainsKey(key))
+                {
+                    RegionInfoByScope ris = null;
+                    if(InfobyScope.TryGetValue(scope, out ris) && ris != null)
+                    {
+                        GridRegion r = timedStorage[key];
+                        if(r != null)
+                            ris.RemoveRegion(r);
+                        if(ris.Count() == 0)
+                            InfobyScope.Remove(scope);
+                    }
+                    timedStorage.Remove(key);
+                    return true;
+                }
+                else
+                    return false;
+            }
+            finally { Monitor.Exit(syncRoot); }
+        }
+
+        public bool TryGetValue(RegionKey key, out GridRegion value)
+        {
+            if (!Monitor.TryEnter(syncRoot, MAX_LOCK_WAIT))
+                throw new ApplicationException("Lock could not be acquired after " + MAX_LOCK_WAIT + "ms");
+            try
+            {
+                if (timedStorage.ContainsKey(key))
+                {
+                    value = timedStorage[key];
+                    return true;
+                }
+            }
+            finally { Monitor.Exit(syncRoot); }
+
+            value = null;
+            return false;
+        }
+
+        public bool TryGetValue(UUID scope, UUID id, out GridRegion value)
+        {
+            if (!Monitor.TryEnter(syncRoot, MAX_LOCK_WAIT))
+                throw new ApplicationException("Lock could not be acquired after " + MAX_LOCK_WAIT + "ms");
+            try
+            {
+                RegionKey rk = new RegionKey(scope, id);
+                if(timedStorage.ContainsKey(rk))
+                {
+                    value = timedStorage[rk];
+                    return true;
+                }
+            }
+            finally { Monitor.Exit(syncRoot); }
+
+            value = null;
+            return false;
+        }
+
+        public bool TryGetValue(UUID scope, string name, out GridRegion value)
+        {
+            if (!Monitor.TryEnter(syncRoot, MAX_LOCK_WAIT))
+                throw new ApplicationException("Lock could not be acquired after " + MAX_LOCK_WAIT + "ms");
+            try
+            {
+                value = null;
+                RegionInfoByScope ris = null;
+                if(!InfobyScope.TryGetValue(scope, out ris) || ris == null)
+                    return false;
+
+                RegionKey key = ris.get(name);
+                if(key == null)
+                    return false;
+
+                if(timedStorage.ContainsKey(key))
+                {
+                    value = timedStorage[key];
+                    return true;
+                }
+            }
+            finally { Monitor.Exit(syncRoot); }
+
+            return false;
+        }
+
+        public bool TryGetValue(UUID scope, ulong handle, out GridRegion value)
+        {
+            if (!Monitor.TryEnter(syncRoot, MAX_LOCK_WAIT))
+                throw new ApplicationException("Lock could not be acquired after " + MAX_LOCK_WAIT + "ms");
+            try
+            {
+                value = null;
+                RegionInfoByScope ris = null;
+                if(!InfobyScope.TryGetValue(scope, out ris) || ris == null)
+                    return false;
+
+                RegionKey key = ris.get(handle);
+                if(key == null)
+                    return false;
+
+                if(timedStorage.ContainsKey(key))
+                {
+                    value = timedStorage[key];
+                    return true;
+                }
+            }
+            finally { Monitor.Exit(syncRoot); }
+
+            value = null;
+            return false;
+        }
+
+        public bool Update(UUID scope, GridRegion region, double expirationSeconds)
+        {
+            if (!Monitor.TryEnter(syncRoot, MAX_LOCK_WAIT))
+                throw new ApplicationException("Lock could not be acquired after " + MAX_LOCK_WAIT + "ms");
+
+            RegionKey key = new RegionKey(scope, region.RegionID);
+            try
+            {
+                if (!timedStorage.ContainsKey(key))
+                    return false;
+
+                timedStorage.Remove(key);
+                key.ExpirationDate = DateTime.UtcNow + TimeSpan.FromSeconds(expirationSeconds);
+                timedStorage.Add(key, region);
+                return true;
+            }
+            finally { Monitor.Exit(syncRoot); }
+        }
+
+        /// <summary>
+        /// Purges expired objects from the cache. Called automatically by the purge timer.
+        /// </summary>
+        private void PurgeCache(object sender, System.Timers.ElapsedEventArgs e)
+        {
+            // Only let one thread purge at once - a buildup could cause a crash
+            // This could cause the purge to be delayed while there are lots of read/write ops 
+            // happening on the cache
+            if (!Monitor.TryEnter(isPurging))
+                return;
+
+            DateTime signalTime = DateTime.UtcNow;
+
+            try
+            {
+                // If we fail to acquire a lock on the synchronization root after MAX_LOCK_WAIT, skip this purge cycle
+                if (!Monitor.TryEnter(syncRoot, MAX_LOCK_WAIT))
+                    return;
+                try
+                {
+                    OpenMetaverse.Lazy<List<object>> expiredItems = new OpenMetaverse.Lazy<List<object>>();
+
+                    foreach (RegionKey timedKey in timedStorage.Keys)
+                    {
+                        if (timedKey.ExpirationDate < signalTime)
+                        {
+                            // Mark the object for purge
+                            expiredItems.Value.Add(timedKey);
+                        }
+                        else
+                        {
+                            break;
+                        }
+                    }
+
+
+                    RegionInfoByScope ris;
+                    if (expiredItems.IsValueCreated)
+                    {
+                        foreach (RegionKey key in expiredItems.Value)
+                        {
+                            ris = null;
+                            if(InfobyScope.TryGetValue(key.ScopeID, out ris) && ris != null)
+                            {
+                                GridRegion r = timedStorage[key];
+                                if(r != null)
+                                    ris.RemoveRegion(r);
+                                
+                                if(ris.Count() == 0)
+                                    InfobyScope.Remove(key.ScopeID);
+                            }
+                            timedStorage.Remove(key);
+                        }
+                    }
+                }
+                finally { Monitor.Exit(syncRoot); }
+            }
+            finally { Monitor.Exit(isPurging); }
+        }
+    }
 }