Concurrent Long and Int histograms

Author: LeeCampbell

src/HdrHistogram.UnitTests/ConcurrentHistogramTestBase.cs

@@ -0,0 +1,31 @@
+using System;
+using System.Linq;
+using System.Threading.Tasks;
+using NUnit.Framework;
+
+namespace HdrHistogram.UnitTests
+{
+    public abstract class ConcurrentHistogramTestBase : HistogramTestBase
+    {
+        [Test]
+        public void Can_support_multiple_concurrent_recorders()
+        {
+            var target = Create(1, long.MaxValue - 1, 3);
+            const int loopcount = 10 * 1000 * 1000;
+            var concurrency = Environment.ProcessorCount;
+            var expected = loopcount * concurrency;
+            Action foo = () =>
+                         {
+                             for (var i = 0; i < loopcount; i++)
+                                 target.RecordValue(i);
+                         };
+
+            var actions = Enumerable.Range(1, concurrency)
+                .Select(_ => foo)
+                .ToArray();
+            Parallel.Invoke(actions);
+
+            Assert.AreEqual(expected, target.TotalCount);
+        }
+    }
+}

src/HdrHistogram.UnitTests/HdrHistogram.UnitTests.csproj

@@ -49,11 +49,16 @@
     <Reference Include="System.Xml" />
   </ItemGroup>
   <ItemGroup>
+    <Compile Include="ConcurrentHistogramTestBase.cs" />
+    <Compile Include="IntConcurrentHistogramTests.cs" />
+    <Compile Include="LongConcurrentHistogramTests.cs" />
     <Compile Include="HistogramAssert.cs" />
     <Compile Include="HistogramEncodingTest.cs" />
     <Compile Include="HistogramIterationValueComparer.cs" />
+    <Compile Include="Persistence\LongConcurrentHistogramLogReaderWriterTests.cs" />
     <Compile Include="Persistence\HistogramLogExtensions.cs" />
     <Compile Include="Persistence\HistogramLogReaderWriterTestBase.cs" />
+    <Compile Include="Persistence\IntConcurrentHistogramLogReaderWriterTests.cs" />
     <Compile Include="Persistence\IntHistogramLogReaderWriterTests.cs" />
     <Compile Include="HistogramTestBase.cs" />
     <Compile Include="IntHistogramTests.cs" />
@@ -65,6 +70,7 @@
     <Compile Include="Persistence\TestCaseGenerator.cs" />
     <Compile Include="Properties\AssemblyInfo.cs" />
     <Compile Include="Recording\RecorderTestsBase.cs" />
+    <Compile Include="Recording\RecorderTestWithConcurrentHistogram.cs" />
     <Compile Include="Recording\RecorderTestWithIntHistogram.cs" />
     <Compile Include="Recording\RecorderTestWithLongHistogram.cs" />
     <Compile Include="Recording\RecorderTestWithLShortHistogram.cs" />

src/HdrHistogram.UnitTests/IntConcurrentHistogramTests.cs

@@ -0,0 +1,20 @@
+using NUnit.Framework;
+
+namespace HdrHistogram.UnitTests
+{
+    [TestFixture]
+    public class IntConcurrentHistogramTests : ConcurrentHistogramTestBase
+    {
+        protected override int WordSize => sizeof(int);
+
+        protected override HistogramBase Create(long highestTrackableValue, int numberOfSignificantValueDigits)
+        {
+            return new IntConcurrentHistogram(1, highestTrackableValue, numberOfSignificantValueDigits);
+        }
+
+        protected override HistogramBase Create(long lowestTrackableValue, long highestTrackableValue, int numberOfSignificantValueDigits)
+        {
+            return new IntConcurrentHistogram(lowestTrackableValue, highestTrackableValue, numberOfSignificantValueDigits);
+        }
+    }
+}

src/HdrHistogram.UnitTests/LongConcurrentHistogramTests.cs

@@ -0,0 +1,20 @@
+using NUnit.Framework;
+
+namespace HdrHistogram.UnitTests
+{
+    [TestFixture]
+    public class LongConcurrentHistogramTests : ConcurrentHistogramTestBase
+    {
+        protected override int WordSize => sizeof(long);
+
+        protected override HistogramBase Create(long highestTrackableValue, int numberOfSignificantValueDigits)
+        {
+            return new LongConcurrentHistogram(1, highestTrackableValue, numberOfSignificantValueDigits);
+        }
+
+        protected override HistogramBase Create(long lowestTrackableValue, long highestTrackableValue, int numberOfSignificantValueDigits)
+        {
+            return new LongConcurrentHistogram(lowestTrackableValue, highestTrackableValue, numberOfSignificantValueDigits);
+        }
+    }
+}

src/HdrHistogram.UnitTests/Persistence/IntConcurrentHistogramLogReaderWriterTests.cs

@@ -0,0 +1,19 @@
+using NUnit.Framework;
+
+namespace HdrHistogram.UnitTests.Persistence
+{
+    [TestFixture]
+    public sealed class IntConcurrentHistogramLogReaderWriterTests : HistogramLogReaderWriterTestBase
+    {
+        protected override HistogramBase Create(long highestTrackableValue, int numberOfSignificantValueDigits)
+        {
+            return new IntConcurrentHistogram(1, highestTrackableValue, numberOfSignificantValueDigits);
+        }
+
+        [Test, TestCaseSource(typeof(TestCaseGenerator), nameof(TestCaseGenerator.PowersOfTwo), new object[] { 31 })]
+        public void CanRoundTripSingleHistogramsWithFullRangesOfCountsAndValues(long count)
+        {
+            RoundTripSingleHistogramsWithFullRangesOfCountsAndValues(count);
+        }
+    }
+}

src/HdrHistogram.UnitTests/Persistence/LongConcurrentHistogramLogReaderWriterTests.cs

@@ -0,0 +1,19 @@
+using NUnit.Framework;
+
+namespace HdrHistogram.UnitTests.Persistence
+{
+    [TestFixture]
+    public sealed class LongConcurrentHistogramLogReaderWriterTests : HistogramLogReaderWriterTestBase
+    {
+        protected override HistogramBase Create(long highestTrackableValue, int numberOfSignificantValueDigits)
+        {
+            return new LongConcurrentHistogram(1, highestTrackableValue, numberOfSignificantValueDigits);
+        }
+
+        [Test, TestCaseSource(typeof(TestCaseGenerator), nameof(TestCaseGenerator.PowersOfTwo), new object[] { 63 })]
+        public void CanRoundTripSingleHistogramsWithFullRangesOfCountsAndValues(long count)
+        {
+            RoundTripSingleHistogramsWithFullRangesOfCountsAndValues(count);
+        }
+    }
+}

src/HdrHistogram.UnitTests/Recording/RecorderTestWithConcurrentHistogram.cs

@@ -0,0 +1,13 @@
+using NUnit.Framework;
+
+namespace HdrHistogram.UnitTests.Recording
+{
+    [TestFixture]
+    public sealed class RecorderTestWithConcurrentHistogram : RecorderTestsBase
+    {
+        protected override HistogramBase Create(long id, long min, long max, int sf)
+        {
+            return new LongConcurrentHistogram(id, min, max, sf);
+        }
+    }
+}

src/HdrHistogram/HdrHistogram.csproj

@@ -46,6 +46,8 @@
     <Reference Include="System.Xml" />
   </ItemGroup>
   <ItemGroup>
+    <Compile Include="IntConcurrentHistogram.cs" />
+    <Compile Include="LongConcurrentHistogram.cs" />
     <Compile Include="HistogramEncoding.cs" />
     <Compile Include="Encoding\HistogramEncoderV2.cs" />
     <Compile Include="Encoding\IEncoder.cs" />
@@ -85,6 +87,8 @@
     <Compile Include="ShortHistogram.cs" />
     <Compile Include="TimeStamp.cs" />
     <Compile Include="Utilities\ArrayExtensions.cs" />
+    <Compile Include="Utilities\AtomicIntArray.cs" />
+    <Compile Include="Utilities\AtomicLongArray.cs" />
     <Compile Include="Utilities\Bitwise.cs" />
     <Compile Include="LongHistogram.cs" />
     <Compile Include="Properties\AssemblyInfo.cs" />

src/HdrHistogram/HistogramBase.cs

@@ -46,6 +46,9 @@ public abstract class HistogramBase : IRecorder
         private long _maxValue;
         private long _minNonZeroValue;
 
+        /// <summary>
+        /// An identifier for the Histogram. Maybe generated by the Recorder if used.
+        /// </summary>
         public long InstanceId { get; }
 
         /// <summary>