add ObjectJobEngine. This is a job engine for jobs (or pool workitems) with same action method but diferent arguments

OpenSim/Framework/ObjectJobEngine.cs

@@ -0,0 +1,189 @@
+/*
+ * 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.
+ */
+
+// A pool of jobs or workitems with same method (callback) but diferent argument (as object) to run in main threadpool
+// can have up to m_concurrency number of execution threads
+// it will hold each thread up to m_threadsHoldtime ms waiting for more work, before releasing it back to the pool.
+
+using System;
+using System.Collections.Concurrent;
+using System.Reflection;
+using System.Threading;
+using log4net;
+
+namespace OpenSim.Framework
+{
+    public class ObjectJobEngine : IDisposable
+    {
+        private static readonly ILog m_log = LogManager.GetLogger(MethodBase.GetCurrentMethod().DeclaringType);
+
+        private readonly object m_mainLock = new object();
+        private readonly string m_name;
+        private readonly int m_threadsHoldtime;
+        private readonly int m_concurrency = 1;
+
+        private BlockingCollection<object> m_jobQueue;
+        private CancellationTokenSource m_cancelSource;
+        private WaitCallback m_callback;
+        private int m_numberThreads = 0;
+        private bool m_isRunning;
+
+        public ObjectJobEngine(WaitCallback callback, string name, int threadsHoldtime = 1000, int concurrency = 1)
+        {
+            m_name = name;
+            m_threadsHoldtime = threadsHoldtime;
+
+            if (concurrency < 1)
+                m_concurrency = 1;
+            else
+                m_concurrency = concurrency;
+
+            if (callback !=  null)
+            {
+                m_callback = callback;
+                m_jobQueue = new BlockingCollection<object>();
+                m_cancelSource = new CancellationTokenSource();
+                m_isRunning = true;
+            }
+        }
+
+        ~ObjectJobEngine()
+        {
+            Dispose(false);
+        }
+
+        public void Dispose()
+        {
+            Dispose(true);
+            GC.SuppressFinalize(this);
+        }
+
+        private void Dispose(bool disposing)
+        {
+            lock(m_mainLock)
+            {
+                if (!m_isRunning)
+                    return;
+                m_isRunning = false;
+
+                m_cancelSource.Cancel();
+            }
+
+            if (m_numberThreads > 0)
+            {
+                int cntr = 100;
+                while (m_numberThreads > 0 && --cntr > 0)
+                    Thread.Yield();
+            }
+
+            if (m_jobQueue != null)
+            {
+                m_jobQueue.Dispose();
+                m_jobQueue = null;
+            }
+            if (m_cancelSource != null)
+            {
+                m_cancelSource.Dispose();
+                m_cancelSource = null;
+            }
+            m_callback = null;
+        }
+
+        /// <summary>
+        /// Number of jobs waiting to be processed.
+        /// </summary>
+        public int JobsWaiting { get { return m_jobQueue == null ? 0 : m_jobQueue.Count; } }
+
+        public void Cancel()
+        {
+            if (!m_isRunning || m_jobQueue == null || m_jobQueue.Count == 0)
+                return;
+            try
+            {
+                while(m_jobQueue.TryTake(out object dummy));
+                m_cancelSource.Cancel();
+            }
+            catch { }
+        }
+
+        /// <summary>
+        /// Queue the job for processing.
+        /// </summary>
+        /// <returns><c>true</c>, if job was queued, <c>false</c> otherwise.</returns>
+        /// <param name="job">The job</param>
+        /// </param>
+        public bool Enqueue(object o)
+        {
+            if (!m_isRunning)
+                return false;
+
+            m_jobQueue?.Add(o);
+
+            lock (m_mainLock)
+            {
+                if (m_numberThreads < m_concurrency && m_numberThreads < m_jobQueue.Count)
+                {
+                    Util.FireAndForget(ProcessRequests, null, m_name, false);
+                    ++m_numberThreads;
+                }
+            }
+            return true;
+        }
+
+        private void ProcessRequests(object o)
+        {
+            object obj;
+            while (m_isRunning)
+            {
+                try
+                {
+                    if(!m_jobQueue.TryTake(out obj, m_threadsHoldtime, m_cancelSource.Token))
+                        break;
+                }
+                catch
+                {
+                    break;
+                }
+
+                if(!m_isRunning || m_callback == null)
+                    break;
+                try
+                {
+                    m_callback.Invoke(obj);
+                    obj = null;
+                }
+                catch (Exception e)
+                {
+                    m_log.ErrorFormat(
+                        "[ObjectJob {0}]: Job failed, continuing.  Exception {1}",m_name, e);
+                }
+            }
+            lock (m_mainLock)
+                --m_numberThreads;
+        }
+    }
+}