implab/ImplabNet Commit - r17:7cd4a843b4e4

Improved worker pool

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r17:7cd4a843b4e4 promises

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r17:7cd4a843b4e4

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Implab.Test/AsyncTests.cs +3 -3

             using System;
             using Microsoft.VisualStudio.TestTools.UnitTesting;
             using System.Reflection;
             using System.Threading;
             using Implab.Parallels;
             namespace Implab.Test {
                 [TestClass]
                 public class AsyncTests {
                     [TestMethod]
                     public void ResolveTest() {
                         int res = -1;
                         var p = new Promise<int>();
                         p.Then(x => res = x);
                         p.Resolve(100);
                         Assert.AreEqual(res, 100);
                     }
                     [TestMethod]
                     public void RejectTest() {
                         int res = -1;
                         Exception err = null;
                         var p = new Promise<int>();
                         p.Then(x => res = x, e => err = e);
                         p.Reject(new ApplicationException("error"));
                         Assert.AreEqual(res, -1);
                         Assert.AreEqual(err.Message, "error");
                     }
                     [TestMethod]
                     public void JoinSuccessTest() {
                         var p = new Promise<int>();
                         p.Resolve(100);
                         Assert.AreEqual(p.Join(), 100);
                     }
                     [TestMethod]
                     public void JoinFailTest() {
                         var p = new Promise<int>();
                         p.Reject(new ApplicationException("failed"));
                         try {
                             p.Join();
                             throw new ApplicationException("WRONG!");
                         } catch (TargetInvocationException err) {
                             Assert.AreEqual(err.InnerException.Message, "failed");
                         } catch {
                             Assert.Fail("Got wrong excaption");
                         }
                     }
                     [TestMethod]
                     public void MapTest() {
                         var p = new Promise<int>();
                         var p2 = p.Map(x => x.ToString());
                         p.Resolve(100);
                         Assert.AreEqual(p2.Join(), "100");
                     }
                     [TestMethod]
                     public void FixErrorTest() {
                         var p = new Promise<int>();
                         var p2 = p.Error(e => 101);
                         p.Reject(new Exception());
                         Assert.AreEqual(p2.Join(), 101);
                     }
                     [TestMethod]
                     public void ChainTest() {
                         var p1 = new Promise<int>();
                         var p3 = p1.Chain(x => {
                             var p2 = new Promise<string>();
                             p2.Resolve(x.ToString());
                             return p2;
                         });
                         p1.Resolve(100);
                         Assert.AreEqual(p3.Join(), "100");
                     }
                     [TestMethod]
                     public void PoolTest() {
                         var pid = Thread.CurrentThread.ManagedThreadId;
                         var p = AsyncPool.Invoke(() => Thread.CurrentThread.ManagedThreadId);
                         Assert.AreNotEqual(pid, p.Join());
                     }
                     [TestMethod]
                     public void WorkerPoolSizeTest() {
-                        var pool = new WorkerPool(5, 10);
+                        var pool = new WorkerPool(5, 10, 0);
                         Assert.AreEqual(5, pool.ThreadCount);
                         pool.Invoke(() => { Thread.Sleep(1000000); return 10; });
                         pool.Invoke(() => { Thread.Sleep(1000000); return 10; });
                         pool.Invoke(() => { Thread.Sleep(1000000); return 10; });
                         Assert.AreEqual(5, pool.ThreadCount);
                         for (int i = 0; i < 100; i++)
                             pool.Invoke(() => { Thread.Sleep(1000000); return 10; });
                         Thread.Sleep(100);
                         Assert.AreEqual(10, pool.ThreadCount);
                         pool.Dispose();
                     }
                     [TestMethod]
                     public void WorkerPoolCorrectTest() {
-                        var pool = new WorkerPool();
+                        var pool = new WorkerPool(0,1000,100);
                         int iterations = 1000;
                         int pending = iterations;
                         var stop = new ManualResetEvent(false);
                         var count = 0;
                         for (int i = 0; i < iterations; i++) {
                             pool
                                 .Invoke(() => 1)
                                 .Then(x => Interlocked.Add(ref count, x))
                                 .Then(x => Math.Log10(x))
                                 .Anyway(() => {
                                     Interlocked.Decrement(ref pending);
                                     if (pending == 0)
                                         stop.Set();
                                 });
                         }
                         stop.WaitOne();
                         Assert.AreEqual(iterations, count);
                         Console.WriteLine("Max threads: {0}", pool.MaxRunningThreads);
                         pool.Dispose();
                     }
                     [TestMethod]
                     public void WorkerPoolDisposeTest() {
                         var pool = new WorkerPool(5, 20);
                         Assert.AreEqual(5, pool.ThreadCount);
                         pool.Dispose();
                         Thread.Sleep(100);
                         Assert.AreEqual(0, pool.ThreadCount);
                         pool.Dispose();
                     }
                     [TestMethod]
                     public void MTQueueTest() {
                         var queue = new MTQueue<int>();
                         int res;
                         queue.Enqueue(10);
                         Assert.IsTrue(queue.TryDequeue(out res));
                         Assert.AreEqual(10, res);
                         Assert.IsFalse(queue.TryDequeue(out res));
                         for (int i = 0; i < 1000; i++)
                             queue.Enqueue(i);
                         for (int i = 0; i < 1000; i++) {
                             queue.TryDequeue(out res);
                             Assert.AreEqual(i, res);
                         }
                         int writers = 0;
                         int readers = 0;
                         var stop = new ManualResetEvent(false);
                         int total = 0;
                         int itemsPerWriter = 1000;
                         int writersCount = 3;
                         for (int i = 0; i < writersCount; i++) {
                             Interlocked.Increment(ref writers);
                             var wn = i;
                             AsyncPool
                                 .InvokeNewThread(() => {
                                     for (int ii = 0; ii < itemsPerWriter; ii++) {
                                         queue.Enqueue(1);
                                     }
                                     return 1;
                                 })
                                 .Anyway(() => Interlocked.Decrement(ref writers));
                         }
                         for (int i = 0; i < 10; i++) {
                             Interlocked.Increment(ref readers);
                             var wn = i;
                             AsyncPool
                                 .InvokeNewThread(() => {
                                     int t;
                                     do {
                                         while (queue.TryDequeue(out t))
                                             Interlocked.Add(ref total, t);
                                     } while (writers > 0);
                                     return 1;
                                 })
                                 .Anyway(() => {
                                     Interlocked.Decrement(ref readers);
                                     if (readers == 0)
                                         stop.Set();
                                 });
                         }
                         stop.WaitOne();
                         Assert.AreEqual(itemsPerWriter * writersCount, total);
                     }
                     [TestMethod]
                     public void ParallelMapTest() {
                         int count = 100000;
                         double[] args = new double[count];
                         var rand = new Random();
                         for (int i = 0; i < count; i++)
                             args[i] = rand.NextDouble();
                         var t = Environment.TickCount;
                         var res = args.ParallelMap(x => Math.Sin(x*x), 4).Join();
                         Console.WriteLine("Map complete in {0} ms", Environment.TickCount - t);
                         t = Environment.TickCount;
                         for (int i = 0; i < count; i++)
                             Assert.AreEqual(Math.Sin(args[i] * args[i]), res[i]);
                         Console.WriteLine("Verified in {0} ms", Environment.TickCount - t);
                     }
                     [TestMethod]
                     public void ChainedMapTest() {
-                        using (var pool = new WorkerPool(1,10)) {
+                        using (var pool = new WorkerPool(8,100,0)) {
                             int count = 10000;
                             double[] args = new double[count];
                             var rand = new Random();
                             for (int i = 0; i < count; i++)
                                 args[i] = rand.NextDouble();
                             var t = Environment.TickCount;
                             var res = args
                                 .ChainedMap(
                                     x => pool.Invoke(
                                         () => Math.Sin(x * x)
                                     ),
                                 )
                                 .Join();
                             Console.WriteLine("Map complete in {0} ms", Environment.TickCount - t);
                             t = Environment.TickCount;
                             for (int i = 0; i < count; i++)
                                 Assert.AreEqual(Math.Sin(args[i] * args[i]), res[i]);
                             Console.WriteLine("Verified in {0} ms", Environment.TickCount - t);
                             Console.WriteLine("Max workers: {0}", pool.MaxRunningThreads);
                         }
                     }
                     [TestMethod]
                     public void ParallelForEachTest() {
                         int count = 100000;
                         int[] args = new int[count];
                         var rand = new Random();
                         for (int i = 0; i < count; i++)
                             args[i] = (int)(rand.NextDouble() * 100);
                         int result = 0;
                         var t = Environment.TickCount;
                         args.ParallelForEach(x => Interlocked.Add(ref result, x), 4).Join();
                         Console.WriteLine("Iteration complete in {0} ms, result: {1}", Environment.TickCount - t, result);
                         int result2 = 0;
                         t = Environment.TickCount;
                         for (int i = 0; i < count; i++)
                             result2 += args[i];
                         Assert.AreEqual(result2, result);
                         Console.WriteLine("Verified in {0} ms", Environment.TickCount - t);
                     }
                     [TestMethod]
                     public void ComplexCase1Test() {
                         var flags = new bool[3];
                         // op1 (aync 200ms) => op2 (async 200ms) => op3 (sync map)
                         var p = PromiseHelper
                             .Sleep(200, "Alan")
                             .Cancelled(() => flags[0] = true)
                             .Chain(x =>
                                 PromiseHelper
                                     .Sleep(200, "Hi, " + x)
                                     .Map(y => y)
                                     .Cancelled(() => flags[1] = true)
                             )
                             .Cancelled(() => flags[2] = true);
                         Thread.Sleep(300);
                         p.Cancel();
                         try {
                             Assert.AreEqual(p.Join(), "Hi, Alan");
                             Assert.Fail("Shouldn't get here");
                         } catch (OperationCanceledException) {
                         }
                         Assert.IsFalse(flags[0]);
                         Assert.IsTrue(flags[1]);
                         Assert.IsTrue(flags[2]);
                     }
                 }
             }

Implab.v11.suo binary modified 0 0

NO CONTENT: modified file, binary diff hidden

Implab/Parallels/DispatchPool.cs +96 -41

             using System;
             using System.Collections.Generic;
             using System.Linq;
             using System.Text;
             using System.Threading;
             using System.Diagnostics;
             namespace Implab.Parallels {
                 public abstract class DispatchPool<TUnit> : IDisposable {
                     readonly int m_minThreads;
                     readonly int m_maxThreads;
                     int m_runningThreads = 0;
                     int m_maxRunningThreads = 0;
                     int m_suspended = 0;
                     int m_exitRequired = 0;
                     AutoResetEvent m_hasTasks = new AutoResetEvent(false);
                     protected DispatchPool(int min, int max) {
                         if (min < 0)
                             throw new ArgumentOutOfRangeException("min");
                         if (max <= 0)
                             throw new ArgumentOutOfRangeException("max");
                         if (min > max)
                             min = max;
                         m_minThreads = min;
                         m_maxThreads = max;
                     }
                     protected DispatchPool(int threads)
                         : this(threads, threads) {
                     }
                     protected DispatchPool() {
                         int maxThreads, maxCP;
                         ThreadPool.GetMaxThreads(out maxThreads, out maxCP);
                         m_minThreads = 0;
                         m_maxThreads = maxThreads;
                     }
                     protected void InitPool() {
                         for (int i = 0; i < m_minThreads; i++)
                             StartWorker();
                     }
                     public int ThreadCount {
                         get {
                             return m_runningThreads;
                         }
                     }
                     public int MaxRunningThreads {
                         get {
                             return m_maxRunningThreads;
                         }
                     }
                     protected bool IsDisposed {
                         get {
                             return m_exitRequired != 0;
                         }
                     }
-                    bool StartWorker() {
+                    protected abstract bool TryDequeue(out TUnit unit);
+                    protected virtual bool ExtendPool() {
+                        if (m_suspended > 0) {
+                            m_hasTasks.Set();
+                            return true;
+                        } else
+                            return StartWorker();
+                    }
+                    /// <summary>
+                    /// Запускает либо новый поток, если раньше не было ни одного потока, либо устанавливает событие пробуждение одного спящего потока
+                    /// </summary>
+                    protected void WakePool() {
+                        m_hasTasks.Set(); // wake sleeping thread;
+                        if (AllocateThreadSlot(1)) {
+                            var worker = new Thread(this.Worker);
+                            worker.IsBackground = true;
+                            worker.Start();
+                        }
+                    }
+                    protected virtual void Suspend() {
+                        m_hasTasks.WaitOne();
+                    }
+                    #region thread slots traits
+                    bool AllocateThreadSlot() {
                         int current;
                         // use spins to allocate slot for the new thread
                         do {
                             current = m_runningThreads;
                             if (current >= m_maxThreads || m_exitRequired != 0)
                                 // no more slots left or the pool has been disposed
                                 return false;
                         } while (current != Interlocked.CompareExchange(ref m_runningThreads, current + 1, current));
-                        m_maxRunningThreads = Math.Max(m_maxRunningThreads, current + 1);
+                        UpdateMaxThreads(current + 1);
+                        return true;
+                    }
+                    bool AllocateThreadSlot(int desired) {
+                        if (desired - 1 != Interlocked.CompareExchange(ref m_runningThreads, desired, desired - 1))
+                            return false;
+                        UpdateMaxThreads(desired);
+                        return true;
+                    }
+                    bool ReleaseThreadSlot(out bool last) {
+                        last = false;
+                        int current;
+                        // use spins to release slot for the new thread
+                        do {
+                            current = m_runningThreads;
+                            if (current <= m_minThreads && m_exitRequired == 0)
+                                // the thread is reserved
+                                return false;
+                        } while (current != Interlocked.CompareExchange(ref m_runningThreads, current - 1, current));
+                        last = (current == 1);
+                        return true;
+                    }
+                    /// <summary>
+                    /// releases thread slot unconditionally, used during cleanup
+                    /// </summary>
+                    /// <returns>true - no more threads left</returns>
+                    bool ReleaseThreadSlotAnyway() {
+                        var left = Interlocked.Decrement(ref m_runningThreads);
+                        return left == 0;
+                    }
+                    void UpdateMaxThreads(int count) {
+                        int max;
+                        do {
+                            max = m_maxRunningThreads;
+                            if (max >= count)
+                                break;
+                        } while(max != Interlocked.CompareExchange(ref m_maxRunningThreads, count, max));
+                    }
+                    #endregion
+                    bool StartWorker() {
+                        if (AllocateThreadSlot()) {
                             // slot successfully allocated
                             var worker = new Thread(this.Worker);
                             worker.IsBackground = true;
                             worker.Start();
                             return true;
+                        } else {
+                            return false;
-                    protected abstract bool TryDequeue(out TUnit unit);
-                    protected virtual void WakeNewWorker(bool extend) {
-                        if (m_suspended > 0)
-                            m_hasTasks.Set();
-                        else
-                            StartWorker();
                         }
-                    /// <summary>
-                    /// Запускает либо новый поток, если раньше не было ни одного потока, либо устанавливает событие пробуждение одного спящего потока
-                    /// </summary>
-                    protected void StartIfIdle() {
-                        int threads;
-                        do {
-                    protected virtual void Suspend() {
-                        m_hasTasks.WaitOne();
                     }
                     bool FetchTask(out TUnit unit) {
                         do {
                             // exit if requested
                             if (m_exitRequired != 0) {
                                 // release the thread slot
-                                var running = Interlocked.Decrement(ref m_runningThreads);
+                                if (ReleaseThreadSlotAnyway()) // it was the last worker
-                                if (running == 0) // it was the last worker
                                     m_hasTasks.Dispose();
                                 else
-                                    m_hasTasks.Set(); // release next worker
+                                    m_hasTasks.Set(); // wake next worker
                                 unit = default(TUnit);
                                 return false;
                             }
                             // fetch task
                             if (TryDequeue(out unit)) {
-                                WakeNewWorker(true);
+                                ExtendPool();
                                 return true;
                             }
                             //no tasks left, exit if the thread is no longer needed
-                            int runningThreads;
+                            bool last;
-                            bool exit = true;
+                            if (ReleaseThreadSlot(out last)) {
-                            do {
+                                if (last && m_hasTasks.WaitOne(0)) {
-                                runningThreads = m_runningThreads;
+                                    if (AllocateThreadSlot(1))
-                                if (runningThreads <= m_minThreads) {
+                                        continue; // spin again...
-                                    // check wheather this is the last thread and we have tasks
+                                    else
+                                        // we failed to reallocate slot for this thread
+                                        // therefore we need to release the event
+                                        m_hasTasks.Set();
+                                }
-                                    exit = false;
-                                    break;
-                            } while (runningThreads != Interlocked.CompareExchange(ref m_runningThreads, runningThreads - 1, runningThreads));
-                            if (exit) {
                                 return false;
                             }
                             // entering suspend state
                             Interlocked.Increment(ref m_suspended);
                             // keep this thread and wait
                             Suspend();
                             Interlocked.Decrement(ref m_suspended);
                         } while (true);
                     }
                     protected abstract void InvokeUnit(TUnit unit);
                     void Worker() {
                         TUnit unit;
                         while (FetchTask(out unit))
                             InvokeUnit(unit);
                     }
                     protected virtual void Dispose(bool disposing) {
                         if (disposing) {
                             if (m_exitRequired == 0) {
                                 if (Interlocked.CompareExchange(ref m_exitRequired, 1, 0) != 0)
                                     return;
                                 // wake sleeping threads
                                 m_hasTasks.Set();
                                 GC.SuppressFinalize(this);
                             }
                         }
                     }
                     public void Dispose() {
                         Dispose(true);
                     }
                     ~DispatchPool() {
                         Dispose(false);
                     }
                 }
             }

Implab/Parallels/WorkerPool.cs +6 -7

             using System;
             using System.Collections.Generic;
             using System.Linq;
             using System.Text;
             using System.Threading;
             using System.Diagnostics;
             namespace Implab.Parallels {
                 public class WorkerPool : DispatchPool<Action> {
                     MTQueue<Action> m_queue = new MTQueue<Action>();
                     int m_queueLength = 0;
                     readonly int m_threshold = 1;
                     public WorkerPool(int minThreads, int maxThreads, int threshold)
                         : base(minThreads, maxThreads) {
                         m_threshold = threshold;
                         InitPool();
                     }
                     public WorkerPool(int minThreads, int maxThreads) :
                         base(minThreads, maxThreads) {
                         InitPool();
                     }
                     public WorkerPool(int threads)
                         : base(threads) {
                         InitPool();
                     }
                     public WorkerPool()
                         : base() {
                         InitPool();
                     }
                     public Promise<T> Invoke<T>(Func<T> task) {
                         if (task == null)
                             throw new ArgumentNullException("task");
                         if (IsDisposed)
                             throw new ObjectDisposedException(ToString());
                         var promise = new Promise<T>();
                         EnqueueTask(delegate() {
                             try {
                                 promise.Resolve(task());
                             } catch (Exception e) {
                                 promise.Reject(e);
                             }
                         });
                         return promise;
                     }
                     protected void EnqueueTask(Action unit) {
                         Debug.Assert(unit != null);
                         var len = Interlocked.Increment(ref m_queueLength);
                         m_queue.Enqueue(unit);
-                        if (ThreadCount == 0)
+                        if(!ExtendPool())
-                            // force to start
+                            WakePool();
-                            WakeNewWorker(false);
                     }
-                    protected override void WakeNewWorker(bool extend) {
+                    protected override bool ExtendPool() {
-                        if (extend && m_queueLength <= m_threshold)
+                        if (m_queueLength <= m_threshold*ThreadCount)
                             // in this case we are in active thread and it request for additional workers
                             // satisfy it only when queue is longer than threshold
-                            return;
+                            return false;
-                        base.WakeNewWorker(extend);
+                        return base.ExtendPool();
                     }
                     protected override bool TryDequeue(out Action unit) {
                         if (m_queue.TryDequeue(out unit)) {
                             Interlocked.Decrement(ref m_queueLength);
                             return true;
                         }
                         return false;
                     }
                     protected override void InvokeUnit(Action unit) {
                         unit();
                     }
                     protected override void Suspend() {
                         if (m_queueLength == 0)
                             base.Suspend();
                     }
                 }
             }

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