* Adds the ability to have a thread efficient long poll service (such as the eventqueue)

* If this doesn't melt the Http Server, this will significantly reduce the number of threads in use on regions with many users.
* Adds AddPollServiceHTTPHandler, and RemovePollServiceHTTPHandler to BaseHttpServer
* Generic enough to be used for many long poll services, not only the EventQueue.

1 files changed, 145 insertions, 0 deletions

diff --git a/OpenSim/Framework/Servers/HttpServer/PollServiceRequestManager.cs b/OpenSim/Framework/Servers/HttpServer/PollServiceRequestManager.cs
new file mode 100644
index 0000000..7f632cf
--- /dev/null
+++ b/OpenSim/Framework/Servers/HttpServer/PollServiceRequestManager.cs
@@ -0,0 +1,145 @@
+/*
+ * 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;
+using System.Threading;
+using HttpServer;
+
+namespace OpenSim.Framework.Servers.HttpServer
+{
+    public class PollServiceRequestManager
+    {
+        private readonly BaseHttpServer m_server;
+        private static Queue m_requests = Queue.Synchronized(new Queue());
+        private uint m_WorkerThreadCount = 0;
+        private Thread[] m_workerThreads;
+        private PollServiceWorkerThread[] m_PollServiceWorkerThreads;
+        private Thread m_watcherThread;
+        private bool m_running = true;
+
+        
+
+        public PollServiceRequestManager(BaseHttpServer pSrv, uint pWorkerThreadCount, int pTimeout)
+        {
+            m_server = pSrv;
+            m_WorkerThreadCount = pWorkerThreadCount;
+            m_workerThreads = new Thread[m_WorkerThreadCount];
+            m_PollServiceWorkerThreads = new PollServiceWorkerThread[m_WorkerThreadCount];
+            m_watcherThread = new Thread(ThreadStart);
+
+            
+            //startup worker threads
+            for (uint i=0;i<m_WorkerThreadCount;i++)
+            {
+                m_PollServiceWorkerThreads[i] = new PollServiceWorkerThread(m_server, pTimeout);
+                m_PollServiceWorkerThreads[i].ReQueue += ReQueueEvent;
+               
+                m_workerThreads[i] = new Thread( m_PollServiceWorkerThreads[i].ThreadStart);
+                m_workerThreads[i].Name = String.Format("PollServiceWorkerThread{0}",i);
+                //Can't add to thread Tracker here Referencing OpenSim.Framework creates circular reference
+                m_workerThreads[i].Start();
+                
+            }
+            //start watcher threads
+            m_watcherThread.Name = "PollServiceWatcherThread";
+            m_watcherThread.Start();
+
+
+        }
+
+        internal void ReQueueEvent(PollServiceHttpRequest req)
+        {
+            // Do accounting stuff here
+            Enqueue(req);
+        }
+
+        public void Enqueue(PollServiceHttpRequest req)
+        {
+            lock (m_requests)
+                m_requests.Enqueue(req);
+        }
+
+        public void ThreadStart(object o)
+        {
+            while (m_running)
+            {
+                ProcessQueuedRequests();
+                Thread.Sleep(1000);
+            }
+        }
+
+        private void ProcessQueuedRequests()
+        {
+            lock (m_requests)
+            {
+                if (m_requests.Count == 0)
+                    return;
+
+                int reqperthread = (int) (m_requests.Count/m_WorkerThreadCount) + 1;
+                // For Each WorkerThread
+                for (int tc = 0; tc < m_WorkerThreadCount && m_requests.Count > 0; tc++)
+                {
+                    //Loop over number of requests each thread handles.
+                    for (int i=0;i<reqperthread && m_requests.Count > 0;i++)
+                    {
+                        try
+                        {
+                            m_PollServiceWorkerThreads[tc].Enqueue((PollServiceHttpRequest)m_requests.Dequeue());
+                        }
+                        catch (InvalidOperationException)
+                        {
+                            // The queue is empty, we did our calculations wrong!
+                            return;
+                        }
+                        
+                    }
+                }
+            }
+            
+        }
+
+
+
+        ~PollServiceRequestManager()
+        {
+            foreach (object o in m_requests)
+            {
+                PollServiceHttpRequest req = (PollServiceHttpRequest) o;
+                m_server.DoHTTPGruntWork(req.PollServiceArgs.NoEvents(), new OSHttpResponse(new HttpResponse(req.HttpContext, req.Request)));
+            }
+
+            m_requests.Clear();
+
+            foreach (Thread t in m_workerThreads)
+            {
+                t.Abort();
+            }
+            m_running = false;
+        }
+    }
+}