5 files changed, 264 insertions, 245 deletions

diff --git a/OpenSim/Framework/Monitoring/Stats/CounterStat.cs b/OpenSim/Framework/Monitoring/Stats/CounterStat.cs
index 318cf1c..318cf1c 100644..100755
--- a/OpenSim/Framework/Monitoring/Stats/CounterStat.cs
+++ b/OpenSim/Framework/Monitoring/Stats/CounterStat.cs
diff --git a/OpenSim/Framework/Monitoring/Stats/EventHistogram.cs b/OpenSim/Framework/Monitoring/Stats/EventHistogram.cs
index f51f322..bc56372 100644..100755
--- a/OpenSim/Framework/Monitoring/Stats/EventHistogram.cs
+++ b/OpenSim/Framework/Monitoring/Stats/EventHistogram.cs
@@ -1,173 +1,173 @@
-/*

- * Copyright (c) Contributors, http://opensimulator.org/

- * See CONTRIBUTORS.TXT for a full list of copyright holders.

- *

- * Redistribution and use in source and binary forms, with or without

- * modification, are permitted provided that the following conditions are met:

- *     * Redistributions of source code must retain the above copyright

- *       notice, this list of conditions and the following disclaimer.

- *     * Redistributions in binary form must reproduce the above copyright

- *       notice, this list of conditions and the following disclaimer in the

- *       documentation and/or other materials provided with the distribution.

- *     * Neither the name of the OpenSimulator Project nor the

- *       names of its contributors may be used to endorse or promote products

- *       derived from this software without specific prior written permission.

- *

- * THIS SOFTWARE IS PROVIDED BY THE DEVELOPERS ``AS IS'' AND ANY

- * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED

- * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE

- * DISCLAIMED. IN NO EVENT SHALL THE CONTRIBUTORS BE LIABLE FOR ANY

- * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES

- * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;

- * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND

- * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT

- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS

- * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

- */

-

-using System;

-using System.Collections.Generic;

-using System.Linq;

-using System.Text;

-

-using OpenMetaverse.StructuredData;

-

-namespace OpenSim.Framework.Monitoring

-{

-// Create a time histogram of events. The histogram is built in a wrap-around

-//   array of equally distributed buckets.

-// For instance, a minute long histogram of second sized buckets would be:

-//          new EventHistogram(60, 1000)

-public class EventHistogram

-{

-    private int m_timeBase;

-    private int m_numBuckets;

-    private int m_bucketMilliseconds;

-    private int m_lastBucket;

-    private int m_totalHistogramMilliseconds;

-    private long[] m_histogram;

-    private object histoLock = new object();

-

-    public EventHistogram(int numberOfBuckets, int millisecondsPerBucket)

-    {

-        m_numBuckets = numberOfBuckets;

-        m_bucketMilliseconds = millisecondsPerBucket;

-        m_totalHistogramMilliseconds = m_numBuckets * m_bucketMilliseconds;

-

-        m_histogram = new long[m_numBuckets];

-        Zero();

-        m_lastBucket = 0;

-        m_timeBase = Util.EnvironmentTickCount();

-    }

-

-    public void Event()

-    {

-        this.Event(1);

-    }

-

-    // Record an event at time 'now' in the histogram.

-    public void Event(int cnt)

-    {

-        lock (histoLock)

-        {

-            // The time as displaced from the base of the histogram

-            int bucketTime = Util.EnvironmentTickCountSubtract(m_timeBase);

-

-            // If more than the total time of the histogram, we just start over

-            if (bucketTime > m_totalHistogramMilliseconds)

-            {

-                Zero();

-                m_lastBucket = 0;

-                m_timeBase = Util.EnvironmentTickCount();

-            }

-            else

-            {

-                // To which bucket should we add this event?

-                int bucket = bucketTime / m_bucketMilliseconds;

-

-                // Advance m_lastBucket to the new bucket. Zero any buckets skipped over.

-                while (bucket != m_lastBucket)

-                {

-                    // Zero from just after the last bucket to the new bucket or the end

-                    for (int jj = m_lastBucket + 1; jj <= Math.Min(bucket, m_numBuckets - 1); jj++)

-                    {

-                        m_histogram[jj] = 0;

-                    }

-                    m_lastBucket = bucket;

-                    // If the new bucket is off the end, wrap around to the beginning

-                    if (bucket > m_numBuckets)

-                    {

-                        bucket -= m_numBuckets;

-                        m_lastBucket = 0;

-                        m_histogram[m_lastBucket] = 0;

-                        m_timeBase += m_totalHistogramMilliseconds;

-                    }

-                }

-            }

-            m_histogram[m_lastBucket] += cnt;

-        }

-    }

-

-    // Get a copy of the current histogram

-    public long[] GetHistogram()

-    {

-        long[] ret = new long[m_numBuckets];

-        lock (histoLock)

-        {

-            int indx = m_lastBucket + 1;

-            for (int ii = 0; ii < m_numBuckets; ii++, indx++)

-            {

-                if (indx >= m_numBuckets)

-                    indx = 0;

-                ret[ii] = m_histogram[indx];

-            }

-        }

-        return ret;

-    }

-

-    public OSDMap GetHistogramAsOSDMap()

-    {

-        OSDMap ret = new OSDMap();

-

-        ret.Add("Buckets", OSD.FromInteger(m_numBuckets));

-        ret.Add("BucketMilliseconds", OSD.FromInteger(m_bucketMilliseconds));

-        ret.Add("TotalMilliseconds", OSD.FromInteger(m_totalHistogramMilliseconds));

-

-        // Compute a number for the first bucket in the histogram.

-        // This will allow readers to know how this histogram relates to any previously read histogram.

-        int baseBucketNum = (m_timeBase / m_bucketMilliseconds) + m_lastBucket + 1;

-        ret.Add("BaseNumber", OSD.FromInteger(baseBucketNum));

-

-        ret.Add("Values", GetHistogramAsOSDArray());

-

-        return ret;

-    }

-    // Get a copy of the current histogram

-    public OSDArray GetHistogramAsOSDArray()

-    {

-        OSDArray ret = new OSDArray(m_numBuckets);

-        lock (histoLock)

-        {

-            int indx = m_lastBucket + 1;

-            for (int ii = 0; ii < m_numBuckets; ii++, indx++)

-            {

-                if (indx >= m_numBuckets)

-                    indx = 0;

-                ret[ii] = OSD.FromLong(m_histogram[indx]);

-            }

-        }

-        return ret;

-    }

-

-    // Zero out the histogram

-    public void Zero()

-    {

-        lock (histoLock)

-        {

-            for (int ii = 0; ii < m_numBuckets; ii++)

-                m_histogram[ii] = 0;

-        }

-    }

-}

-

-}

+/*
+ * Copyright (c) Contributors, http://opensimulator.org/
+ * See CONTRIBUTORS.TXT for a full list of copyright holders.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *     * Redistributions of source code must retain the above copyright
+ *       notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above copyright
+ *       notice, this list of conditions and the following disclaimer in the
+ *       documentation and/or other materials provided with the distribution.
+ *     * Neither the name of the OpenSimulator Project nor the
+ *       names of its contributors may be used to endorse or promote products
+ *       derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE DEVELOPERS ``AS IS'' AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE CONTRIBUTORS BE LIABLE FOR ANY
+ * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+
+using OpenMetaverse.StructuredData;
+
+namespace OpenSim.Framework.Monitoring
+{
+// Create a time histogram of events. The histogram is built in a wrap-around
+//   array of equally distributed buckets.
+// For instance, a minute long histogram of second sized buckets would be:
+//          new EventHistogram(60, 1000)
+public class EventHistogram
+{
+    private int m_timeBase;
+    private int m_numBuckets;
+    private int m_bucketMilliseconds;
+    private int m_lastBucket;
+    private int m_totalHistogramMilliseconds;
+    private long[] m_histogram;
+    private object histoLock = new object();
+
+    public EventHistogram(int numberOfBuckets, int millisecondsPerBucket)
+    {
+        m_numBuckets = numberOfBuckets;
+        m_bucketMilliseconds = millisecondsPerBucket;
+        m_totalHistogramMilliseconds = m_numBuckets * m_bucketMilliseconds;
+
+        m_histogram = new long[m_numBuckets];
+        Zero();
+        m_lastBucket = 0;
+        m_timeBase = Util.EnvironmentTickCount();
+    }
+
+    public void Event()
+    {
+        this.Event(1);
+    }
+
+    // Record an event at time 'now' in the histogram.
+    public void Event(int cnt)
+    {
+        lock (histoLock)
+        {
+            // The time as displaced from the base of the histogram
+            int bucketTime = Util.EnvironmentTickCountSubtract(m_timeBase);
+
+            // If more than the total time of the histogram, we just start over
+            if (bucketTime > m_totalHistogramMilliseconds)
+            {
+                Zero();
+                m_lastBucket = 0;
+                m_timeBase = Util.EnvironmentTickCount();
+            }
+            else
+            {
+                // To which bucket should we add this event?
+                int bucket = bucketTime / m_bucketMilliseconds;
+
+                // Advance m_lastBucket to the new bucket. Zero any buckets skipped over.
+                while (bucket != m_lastBucket)
+                {
+                    // Zero from just after the last bucket to the new bucket or the end
+                    for (int jj = m_lastBucket + 1; jj <= Math.Min(bucket, m_numBuckets - 1); jj++)
+                    {
+                        m_histogram[jj] = 0;
+                    }
+                    m_lastBucket = bucket;
+                    // If the new bucket is off the end, wrap around to the beginning
+                    if (bucket > m_numBuckets)
+                    {
+                        bucket -= m_numBuckets;
+                        m_lastBucket = 0;
+                        m_histogram[m_lastBucket] = 0;
+                        m_timeBase += m_totalHistogramMilliseconds;
+                    }
+                }
+            }
+            m_histogram[m_lastBucket] += cnt;
+        }
+    }
+
+    // Get a copy of the current histogram
+    public long[] GetHistogram()
+    {
+        long[] ret = new long[m_numBuckets];
+        lock (histoLock)
+        {
+            int indx = m_lastBucket + 1;
+            for (int ii = 0; ii < m_numBuckets; ii++, indx++)
+            {
+                if (indx >= m_numBuckets)
+                    indx = 0;
+                ret[ii] = m_histogram[indx];
+            }
+        }
+        return ret;
+    }
+
+    public OSDMap GetHistogramAsOSDMap()
+    {
+        OSDMap ret = new OSDMap();
+
+        ret.Add("Buckets", OSD.FromInteger(m_numBuckets));
+        ret.Add("BucketMilliseconds", OSD.FromInteger(m_bucketMilliseconds));
+        ret.Add("TotalMilliseconds", OSD.FromInteger(m_totalHistogramMilliseconds));
+
+        // Compute a number for the first bucket in the histogram.
+        // This will allow readers to know how this histogram relates to any previously read histogram.
+        int baseBucketNum = (m_timeBase / m_bucketMilliseconds) + m_lastBucket + 1;
+        ret.Add("BaseNumber", OSD.FromInteger(baseBucketNum));
+
+        ret.Add("Values", GetHistogramAsOSDArray());
+
+        return ret;
+    }
+    // Get a copy of the current histogram
+    public OSDArray GetHistogramAsOSDArray()
+    {
+        OSDArray ret = new OSDArray(m_numBuckets);
+        lock (histoLock)
+        {
+            int indx = m_lastBucket + 1;
+            for (int ii = 0; ii < m_numBuckets; ii++, indx++)
+            {
+                if (indx >= m_numBuckets)
+                    indx = 0;
+                ret[ii] = OSD.FromLong(m_histogram[indx]);
+            }
+        }
+        return ret;
+    }
+
+    // Zero out the histogram
+    public void Zero()
+    {
+        lock (histoLock)
+        {
+            for (int ii = 0; ii < m_numBuckets; ii++)
+                m_histogram[ii] = 0;
+        }
+    }
+}
+
+}
diff --git a/OpenSim/Framework/Monitoring/Stats/Stat.cs b/OpenSim/Framework/Monitoring/Stats/Stat.cs
index a7cb2a6..2402acd 100644
--- a/OpenSim/Framework/Monitoring/Stats/Stat.cs
+++ b/OpenSim/Framework/Monitoring/Stats/Stat.cs
@@ -121,17 +121,17 @@ namespace OpenSim.Framework.Monitoring
             string container,
             StatType type,
             Action<Stat> pullAction,
-            StatVerbosity verbosity) 
+            StatVerbosity verbosity)
                 : this(
-                    shortName, 
-                    name, 
-                    description, 
-                    unitName, 
-                    category, 
-                    container, 
-                    type, 
-                    MeasuresOfInterest.None, 
-                    pullAction, 
+                    shortName,
+                    name,
+                    description,
+                    unitName,
+                    category,
+                    container,
+                    type,
+                    MeasuresOfInterest.None,
+                    pullAction,
                     verbosity)
         {
         }
@@ -227,11 +227,11 @@ namespace OpenSim.Framework.Monitoring
         {
             StringBuilder sb = new StringBuilder();
             sb.AppendFormat(
-                "{0}.{1}.{2} : {3}{4}", 
-                Category, 
-                Container, 
-                ShortName, 
-                Value, 
+                "{0}.{1}.{2} : {3}{4}",
+                Category,
+                Container,
+                ShortName,
+                Value,
                 string.IsNullOrEmpty(UnitName) ? "" : string.Format(" {0}", UnitName));
 
             AppendMeasuresOfInterest(sb);
@@ -239,6 +239,17 @@ namespace OpenSim.Framework.Monitoring
             return sb.ToString();
         }
 
+        public virtual OSDMap ToBriefOSDMap()
+        {
+            OSDMap ret = new OSDMap();
+
+            ret.Add("Value", OSD.FromReal(Value));
+
+            double lastChangeOverTime, averageChangeOverTime;
+
+            return ret;
+        }
+
         public virtual OSDMap ToOSDMap()
         {
             OSDMap ret = new OSDMap();
@@ -279,7 +290,7 @@ namespace OpenSim.Framework.Monitoring
                 lock (m_samples)
                 {
                     //                    m_log.DebugFormat(
-                    //                        "[STAT]: Samples for {0} are {1}", 
+                    //                        "[STAT]: Samples for {0} are {1}",
                     //                        Name, string.Join(",", m_samples.Select(s => s.ToString()).ToArray()));
 
                     foreach (double s in m_samples)
@@ -315,12 +326,12 @@ namespace OpenSim.Framework.Monitoring
             if (ComputeMeasuresOfInterest(out lastChangeOverTime, out averageChangeOverTime))
             {
                 sb.AppendFormat(
-                    ", {0:0.##}{1}/s, {2:0.##}{3}/s", 
-                    lastChangeOverTime, 
-                    string.IsNullOrEmpty(UnitName) ? "" : string.Format(" {0}", UnitName), 
+                    ", {0:0.##}{1}/s, {2:0.##}{3}/s",
+                    lastChangeOverTime,
+                    string.IsNullOrEmpty(UnitName) ? "" : string.Format(" {0}", UnitName),
                     averageChangeOverTime,
                     string.IsNullOrEmpty(UnitName) ? "" : string.Format(" {0}", UnitName));
             }
         }
     }
-}
\ No newline at end of file
+}
diff --git a/OpenSim/Framework/Monitoring/StatsLogger.cs b/OpenSim/Framework/Monitoring/StatsLogger.cs
index 15a37aa..b719af9 100644
--- a/OpenSim/Framework/Monitoring/StatsLogger.cs
+++ b/OpenSim/Framework/Monitoring/StatsLogger.cs
@@ -99,13 +99,13 @@ namespace OpenSim.Framework.Monitoring
             }
 
             string path = cmd[2];
-            
+
             using (StreamWriter sw = new StreamWriter(path, true))
             {
                 foreach (string line in GetReport())
                     sw.WriteLine(line);
-            }   
-            
+            }
+
             MainConsole.Instance.OutputFormat("Stats saved to file {0}", path);
         }
 
diff --git a/OpenSim/Framework/Monitoring/StatsManager.cs b/OpenSim/Framework/Monitoring/StatsManager.cs
index 3136ee8..a6b341f 100644
--- a/OpenSim/Framework/Monitoring/StatsManager.cs
+++ b/OpenSim/Framework/Monitoring/StatsManager.cs
@@ -47,6 +47,8 @@ namespace OpenSim.Framework.Monitoring
         // Subcommand used to list other stats.
         public const string ListSubCommand = "list";
 
+        public static string StatsPassword { get; set; }
+
         // All subcommands
         public static HashSet<string> SubCommands = new HashSet<string> { AllSubCommand, ListSubCommand };
 
@@ -80,8 +82,7 @@ namespace OpenSim.Framework.Monitoring
                     + "'all' will show all statistics.\n"
                     + "A <category> name will show statistics from that category.\n"
                     + "A <category>.<container> name will show statistics from that category in that container.\n"
-                    + "More than one name can be given separated by spaces.\n"
-                    + "THIS STATS FACILITY IS EXPERIMENTAL AND DOES NOT YET CONTAIN ALL STATS",
+                    + "More than one name can be given separated by spaces.\n",
                 HandleShowStatsCommand);
 
             console.Commands.AddCommand(
@@ -91,7 +92,6 @@ namespace OpenSim.Framework.Monitoring
                 "show stats [list|all|(<category>[.<container>])+",
                 "Alias for 'stats show' command",
                 HandleShowStatsCommand);
-
             StatsLogger.RegisterConsoleCommands(console);
         }
 
@@ -262,33 +262,36 @@ namespace OpenSim.Framework.Monitoring
         {
             OSDMap map = new OSDMap();
 
-            foreach (string catName in RegisteredStats.Keys)
+            lock (RegisteredStats)
             {
-                // Do this category if null spec, "all" subcommand or category name matches passed parameter.
-                // Skip category if none of the above.
-                if (!(String.IsNullOrEmpty(pCategoryName) || pCategoryName == AllSubCommand || pCategoryName == catName))
-                    continue;
-
-                OSDMap contMap = new OSDMap();
-                foreach (string contName in RegisteredStats[catName].Keys)
+                foreach (string catName in RegisteredStats.Keys)
                 {
-                    if (!(string.IsNullOrEmpty(pContainerName) || pContainerName == AllSubCommand || pContainerName == contName))
+                    // Do this category if null spec, "all" subcommand or category name matches passed parameter.
+                    // Skip category if none of the above.
+                    if (!(String.IsNullOrEmpty(pCategoryName) || pCategoryName == AllSubCommand || pCategoryName == catName))
                         continue;
-                    
-                    OSDMap statMap = new OSDMap();
 
-                    SortedDictionary<string, Stat> theStats = RegisteredStats[catName][contName];
-                    foreach (string statName in theStats.Keys)
+                    OSDMap contMap = new OSDMap();
+                    foreach (string contName in RegisteredStats[catName].Keys)
                     {
-                        if (!(String.IsNullOrEmpty(pStatName) || pStatName == AllSubCommand || pStatName == statName))
+                        if (!(string.IsNullOrEmpty(pContainerName) || pContainerName == AllSubCommand || pContainerName == contName))
                             continue;
 
-                        statMap.Add(statName, theStats[statName].ToOSDMap());
-                    }
+                        OSDMap statMap = new OSDMap();
+
+                        SortedDictionary<string, Stat> theStats = RegisteredStats[catName][contName];
+                        foreach (string statName in theStats.Keys)
+                        {
+                            if (!(String.IsNullOrEmpty(pStatName) || pStatName == AllSubCommand || pStatName == statName))
+                                continue;
+
+                            statMap.Add(statName, theStats[statName].ToBriefOSDMap());
+                        }
 
-                    contMap.Add(contName, statMap);
+                        contMap.Add(contName, statMap);
+                    }
+                    map.Add(catName, contMap);
                 }
-                map.Add(catName, contMap);
             }
 
             return map;
@@ -301,6 +304,17 @@ namespace OpenSim.Framework.Monitoring
             int response_code = 200;
             string contenttype = "text/json";
 
+            if (StatsPassword != String.Empty && (!request.ContainsKey("pass") || request["pass"].ToString() != StatsPassword))
+            {
+                responsedata["int_response_code"] = response_code;
+                responsedata["content_type"] = "text/plain";
+                responsedata["keepalive"] = false;
+                responsedata["str_response_string"] = "Access denied";
+                responsedata["access_control_allow_origin"] = "*";
+
+                return responsedata;
+            }
+
             string pCategoryName = StatsManager.AllSubCommand;
             string pContainerName = StatsManager.AllSubCommand;
             string pStatName = StatsManager.AllSubCommand;
@@ -358,8 +372,8 @@ namespace OpenSim.Framework.Monitoring
         /// <returns></returns>
         public static bool RegisterStat(Stat stat)
         {
-            SortedDictionary<string, SortedDictionary<string, Stat>> category = null, newCategory;
-            SortedDictionary<string, Stat> container = null, newContainer;
+            SortedDictionary<string, SortedDictionary<string, Stat>> category = null;
+            SortedDictionary<string, Stat> container = null;
 
             lock (RegisteredStats)
             {
@@ -369,22 +383,15 @@ namespace OpenSim.Framework.Monitoring
                 if (TryGetStatParents(stat, out category, out container))
                     return false;
 
-                // We take a copy-on-write approach here of replacing dictionaries when keys are added or removed.
-                // This means that we don't need to lock or copy them on iteration, which will be a much more
-                // common operation after startup.
-                if (container != null)
-                    newContainer = new SortedDictionary<string, Stat>(container);
-                else
-                    newContainer = new SortedDictionary<string, Stat>();
+                if (container == null)
+                    container = new SortedDictionary<string, Stat>();
 
-                if (category != null)
-                    newCategory = new SortedDictionary<string, SortedDictionary<string, Stat>>(category);
-                else
-                    newCategory = new SortedDictionary<string, SortedDictionary<string, Stat>>();
+                if (category == null)
+                    category = new SortedDictionary<string, SortedDictionary<string, Stat>>();
 
-                newContainer[stat.ShortName] = stat;
-                newCategory[stat.Container] = newContainer;
-                RegisteredStats[stat.Category] = newCategory;
+                container[stat.ShortName] = stat;
+                category[stat.Container] = container;
+                RegisteredStats[stat.Category] = category;
             }
 
             return true;
@@ -397,23 +404,24 @@ namespace OpenSim.Framework.Monitoring
         /// <returns></returns>
         public static bool DeregisterStat(Stat stat)
         {
-            SortedDictionary<string, SortedDictionary<string, Stat>> category = null, newCategory;
-            SortedDictionary<string, Stat> container = null, newContainer;
+            SortedDictionary<string, SortedDictionary<string, Stat>> category = null;
+            SortedDictionary<string, Stat> container = null;
 
             lock (RegisteredStats)
             {
                 if (!TryGetStatParents(stat, out category, out container))
                     return false;
 
-                newContainer = new SortedDictionary<string, Stat>(container);
-                newContainer.Remove(stat.ShortName);
-
-                newCategory = new SortedDictionary<string, SortedDictionary<string, Stat>>(category);
-                newCategory.Remove(stat.Container);
-
-                newCategory[stat.Container] = newContainer;
-                RegisteredStats[stat.Category] = newCategory;
-
+                if(container != null)
+                {
+                    container.Remove(stat.ShortName);
+                    if(category != null && container.Count == 0)
+                    {
+                        category.Remove(stat.Container);
+                        if(category.Count == 0)
+                            RegisteredStats.Remove(stat.Category);
+                    }
+                }
                 return true;
             }
         }
@@ -554,4 +562,4 @@ namespace OpenSim.Framework.Monitoring
         Debug,
         Info
     }
-}
\ No newline at end of file
+}