From 5aec0ff207e9427b8756471eb003fd68859f67b1 Mon Sep 17 00:00:00 2001 From: Justin Clark-Casey (justincc) Date: Wed, 25 Jul 2012 23:27:00 +0100 Subject: Move Watchdog and MemoryWatchdog classes into OpenSim.Framework.Monitoring with other monitoring code from OpenSim.Framework --- OpenSim/Framework/Monitoring/Watchdog.cs | 334 +++++++++++++++++++++++++++++++ 1 file changed, 334 insertions(+) create mode 100644 OpenSim/Framework/Monitoring/Watchdog.cs (limited to 'OpenSim/Framework/Monitoring/Watchdog.cs') diff --git a/OpenSim/Framework/Monitoring/Watchdog.cs b/OpenSim/Framework/Monitoring/Watchdog.cs new file mode 100644 index 0000000..d4cf02f --- /dev/null +++ b/OpenSim/Framework/Monitoring/Watchdog.cs @@ -0,0 +1,334 @@ +/* + * 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.Threading; +using log4net; + +namespace OpenSim.Framework.Monitoring +{ + /// + /// Manages launching threads and keeping watch over them for timeouts + /// + public static class Watchdog + { + /// Timer interval in milliseconds for the watchdog timer + const double WATCHDOG_INTERVAL_MS = 2500.0d; + + /// Default timeout in milliseconds before a thread is considered dead + public const int DEFAULT_WATCHDOG_TIMEOUT_MS = 5000; + + [System.Diagnostics.DebuggerDisplay("{Thread.Name}")] + public class ThreadWatchdogInfo + { + public Thread Thread { get; private set; } + + /// + /// Approximate tick when this thread was started. + /// + /// + /// Not terribly good since this quickly wraps around. + /// + public int FirstTick { get; private set; } + + /// + /// Last time this heartbeat update was invoked + /// + public int LastTick { get; set; } + + /// + /// Number of milliseconds before we notify that the thread is having a problem. + /// + public int Timeout { get; set; } + + /// + /// Is this thread considered timed out? + /// + public bool IsTimedOut { get; set; } + + /// + /// Will this thread trigger the alarm function if it has timed out? + /// + public bool AlarmIfTimeout { get; set; } + + /// + /// Method execute if alarm goes off. If null then no alarm method is fired. + /// + public Func AlarmMethod { get; set; } + + public ThreadWatchdogInfo(Thread thread, int timeout) + { + Thread = thread; + Timeout = timeout; + FirstTick = Environment.TickCount & Int32.MaxValue; + LastTick = FirstTick; + } + } + + /// + /// This event is called whenever a tracked thread is + /// stopped or has not called UpdateThread() in time< + /// /summary> + public static event Action OnWatchdogTimeout; + + private static readonly ILog m_log = LogManager.GetLogger(System.Reflection.MethodBase.GetCurrentMethod().DeclaringType); + private static Dictionary m_threads; + private static System.Timers.Timer m_watchdogTimer; + + /// + /// Last time the watchdog thread ran. + /// + /// + /// Should run every WATCHDOG_INTERVAL_MS + /// + public static int LastWatchdogThreadTick { get; private set; } + + static Watchdog() + { + m_threads = new Dictionary(); + m_watchdogTimer = new System.Timers.Timer(WATCHDOG_INTERVAL_MS); + m_watchdogTimer.AutoReset = false; + m_watchdogTimer.Elapsed += WatchdogTimerElapsed; + + // Set now so we don't get alerted on the first run + LastWatchdogThreadTick = Environment.TickCount & Int32.MaxValue; + + m_watchdogTimer.Start(); + } + + /// + /// Start a new thread that is tracked by the watchdog timer. + /// + /// The method that will be executed in a new thread + /// A name to give to the new thread + /// Priority to run the thread at + /// True to run this thread as a background thread, otherwise false + /// Trigger an alarm function is we have timed out + /// The newly created Thread object + public static Thread StartThread( + ThreadStart start, string name, ThreadPriority priority, bool isBackground, bool alarmIfTimeout) + { + return StartThread(start, name, priority, isBackground, alarmIfTimeout, null, DEFAULT_WATCHDOG_TIMEOUT_MS); + } + + /// + /// Start a new thread that is tracked by the watchdog timer + /// + /// The method that will be executed in a new thread + /// A name to give to the new thread + /// Priority to run the thread at + /// True to run this thread as a background + /// thread, otherwise false + /// Trigger an alarm function is we have timed out + /// + /// Alarm method to call if alarmIfTimeout is true and there is a timeout. + /// Normally, this will just return some useful debugging information. + /// + /// Number of milliseconds to wait until we issue a warning about timeout. + /// The newly created Thread object + public static Thread StartThread( + ThreadStart start, string name, ThreadPriority priority, bool isBackground, + bool alarmIfTimeout, Func alarmMethod, int timeout) + { + Thread thread = new Thread(start); + thread.Name = name; + thread.Priority = priority; + thread.IsBackground = isBackground; + + ThreadWatchdogInfo twi + = new ThreadWatchdogInfo(thread, timeout) + { AlarmIfTimeout = alarmIfTimeout, AlarmMethod = alarmMethod }; + + m_log.DebugFormat( + "[WATCHDOG]: Started tracking thread {0}, ID {1}", twi.Thread.Name, twi.Thread.ManagedThreadId); + + lock (m_threads) + m_threads.Add(twi.Thread.ManagedThreadId, twi); + + thread.Start(); + + return thread; + } + + /// + /// Marks the current thread as alive + /// + public static void UpdateThread() + { + UpdateThread(Thread.CurrentThread.ManagedThreadId); + } + + /// + /// Stops watchdog tracking on the current thread + /// + /// + /// True if the thread was removed from the list of tracked + /// threads, otherwise false + /// + public static bool RemoveThread() + { + return RemoveThread(Thread.CurrentThread.ManagedThreadId); + } + + private static bool RemoveThread(int threadID) + { + lock (m_threads) + return m_threads.Remove(threadID); + } + + public static bool AbortThread(int threadID) + { + lock (m_threads) + { + if (m_threads.ContainsKey(threadID)) + { + ThreadWatchdogInfo twi = m_threads[threadID]; + twi.Thread.Abort(); + RemoveThread(threadID); + + return true; + } + else + { + return false; + } + } + } + + private static void UpdateThread(int threadID) + { + ThreadWatchdogInfo threadInfo; + + // Although TryGetValue is not a thread safe operation, we use a try/catch here instead + // of a lock for speed. Adding/removing threads is a very rare operation compared to + // UpdateThread(), and a single UpdateThread() failure here and there won't break + // anything + try + { + if (m_threads.TryGetValue(threadID, out threadInfo)) + { + threadInfo.LastTick = Environment.TickCount & Int32.MaxValue; + threadInfo.IsTimedOut = false; + } + else + { + m_log.WarnFormat("[WATCHDOG]: Asked to update thread {0} which is not being monitored", threadID); + } + } + catch { } + } + + /// + /// Get currently watched threads for diagnostic purposes + /// + /// + public static ThreadWatchdogInfo[] GetThreadsInfo() + { + lock (m_threads) + return m_threads.Values.ToArray(); + } + + /// + /// Return the current thread's watchdog info. + /// + /// The watchdog info. null if the thread isn't being monitored. + public static ThreadWatchdogInfo GetCurrentThreadInfo() + { + lock (m_threads) + { + if (m_threads.ContainsKey(Thread.CurrentThread.ManagedThreadId)) + return m_threads[Thread.CurrentThread.ManagedThreadId]; + } + + return null; + } + + /// + /// Check watched threads. Fire alarm if appropriate. + /// + /// + /// + private static void WatchdogTimerElapsed(object sender, System.Timers.ElapsedEventArgs e) + { + int now = Environment.TickCount & Int32.MaxValue; + int msElapsed = now - LastWatchdogThreadTick; + + if (msElapsed > WATCHDOG_INTERVAL_MS * 2) + m_log.WarnFormat( + "[WATCHDOG]: {0} ms since Watchdog last ran. Interval should be approximately {1} ms", + msElapsed, WATCHDOG_INTERVAL_MS); + + LastWatchdogThreadTick = Environment.TickCount & Int32.MaxValue; + + Action callback = OnWatchdogTimeout; + + if (callback != null) + { + List callbackInfos = null; + + lock (m_threads) + { + foreach (ThreadWatchdogInfo threadInfo in m_threads.Values) + { + if (threadInfo.Thread.ThreadState == ThreadState.Stopped) + { + RemoveThread(threadInfo.Thread.ManagedThreadId); + + if (callbackInfos == null) + callbackInfos = new List(); + + callbackInfos.Add(threadInfo); + } + else if (!threadInfo.IsTimedOut && now - threadInfo.LastTick >= threadInfo.Timeout) + { + threadInfo.IsTimedOut = true; + + if (threadInfo.AlarmIfTimeout) + { + if (callbackInfos == null) + callbackInfos = new List(); + + callbackInfos.Add(threadInfo); + } + } + } + } + + if (callbackInfos != null) + foreach (ThreadWatchdogInfo callbackInfo in callbackInfos) + callback(callbackInfo); + } + + if (MemoryWatchdog.Enabled) + MemoryWatchdog.Update(); + + m_watchdogTimer.Start(); + } + } +} \ No newline at end of file -- cgit v1.1