bitfaster · bitfaster · Sep 9, 2022 · Sep 9, 2022
diff --git a/BitFaster.Caching.Benchmarks/Lfu/LfuJustGetOrAdd.cs b/BitFaster.Caching.Benchmarks/Lfu/LfuJustGetOrAdd.cs
@@ -22,11 +22,11 @@ public class LfuJustGetOrAdd
 
         const int stripes = 1;
         private static readonly BackgroundThreadScheduler background = new BackgroundThreadScheduler();
-        private static readonly ConcurrentLfu<int, int> concurrentLfu = new ConcurrentLfu<int, int>(stripes, 9, background, EqualityComparer<int>.Default, LfuBufferSize.Default(1, 128));
+        private static readonly ConcurrentLfu<int, int> concurrentLfu = new ConcurrentLfu<int, int>(stripes, 9, background, EqualityComparer<int>.Default);
 
-        private static readonly ConcurrentLfu<int, int> concurrentLfuFore = new ConcurrentLfu<int, int>(stripes, 9, new ForegroundScheduler(), EqualityComparer<int>.Default, LfuBufferSize.Default(1, 128));
-        private static readonly ConcurrentLfu<int, int> concurrentLfuTp = new ConcurrentLfu<int, int>(stripes, 9, new ThreadPoolScheduler(), EqualityComparer<int>.Default, LfuBufferSize.Default(1, 128));
-        private static readonly ConcurrentLfu<int, int> concurrentLfuNull = new ConcurrentLfu<int, int>(stripes, 9, new NullScheduler(), EqualityComparer<int>.Default, LfuBufferSize.Default(1, 128));
+        private static readonly ConcurrentLfu<int, int> concurrentLfuFore = new ConcurrentLfu<int, int>(stripes, 9, new ForegroundScheduler(), EqualityComparer<int>.Default);
+        private static readonly ConcurrentLfu<int, int> concurrentLfuTp = new ConcurrentLfu<int, int>(stripes, 9, new ThreadPoolScheduler(), EqualityComparer<int>.Default);
+        private static readonly ConcurrentLfu<int, int> concurrentLfuNull = new ConcurrentLfu<int, int>(stripes, 9, new NullScheduler(), EqualityComparer<int>.Default);
 
         [GlobalSetup]
         public void GlobalSetup()

diff --git a/BitFaster.Caching.Benchmarks/Lru/LruJustGetOrAdd.cs b/BitFaster.Caching.Benchmarks/Lru/LruJustGetOrAdd.cs
@@ -48,7 +48,7 @@ public class LruJustGetOrAdd
         private static readonly ICache<int, int> atomicFastLru = new ConcurrentLruBuilder<int, int>().WithConcurrencyLevel(8).WithCapacity(9).WithAtomicGetOrAdd().Build();
 
         private static readonly BackgroundThreadScheduler background = new BackgroundThreadScheduler();
-        private static readonly ConcurrentLfu<int, int> concurrentLfu = new ConcurrentLfu<int, int>(1, 9, background, EqualityComparer<int>.Default, LfuBufferSize.Default(1, 128));
+        private static readonly ConcurrentLfu<int, int> concurrentLfu = new ConcurrentLfu<int, int>(1, 9, background, EqualityComparer<int>.Default);
 
 
         private static readonly int key = 1;

diff --git a/BitFaster.Caching.HitRateAnalysis/Analysis.cs b/BitFaster.Caching.HitRateAnalysis/Analysis.cs
@@ -2,9 +2,6 @@
 using System.Collections.Generic;
 using System.Globalization;
 using System.IO;
-using System.Linq;
-using System.Text;
-using System.Threading.Tasks;
 using BitFaster.Caching.Lfu;
 using BitFaster.Caching.Lru;
 using BitFaster.Caching.Scheduler;
@@ -22,7 +19,7 @@ public Analysis(int cacheSize)
         {
             concurrentLru = new ConcurrentLru<K, int>(1, cacheSize, EqualityComparer<K>.Default);
             classicLru = new ClassicLru<K, int>(1, cacheSize, EqualityComparer<K>.Default);
-            concurrentLfu = new ConcurrentLfu<K, int>(1, cacheSize, new ForegroundScheduler(), EqualityComparer<K>.Default, LfuBufferSize.Default(1, 128));
+            concurrentLfu = new ConcurrentLfu<K, int>(1, cacheSize, new ForegroundScheduler(), EqualityComparer<K>.Default);
         }
 
         public int CacheSize => concurrentLru.Capacity;

diff --git a/BitFaster.Caching.ThroughputAnalysis/Program.cs b/BitFaster.Caching.ThroughputAnalysis/Program.cs
@@ -22,7 +22,7 @@ class Program
         const double s = 0.86;
         const int n = 500;
         static int capacity = 500;
-        const int maxThreads = 64;
+        const int maxThreads = 52;
         const int sampleCount = 2000;
         const int repeatCount = 400;
 
@@ -58,7 +58,6 @@ static void Main(string[] args)
                 resultTable.Columns.Add(tc.ToString());
             }
 
-
             DataRow classicLru = resultTable.NewRow();
             DataRow memoryCache = resultTable.NewRow();
             DataRow concurrentLru = resultTable.NewRow();
@@ -102,7 +101,7 @@ static void Main(string[] args)
                 for (int i = 0; i < warmup + runs; i++)
                 {
                     var scheduler = new BackgroundThreadScheduler();
-                    results[i] = MeasureThroughput(new ConcurrentLfu<int, int>(concurrencyLevel: tc, capacity: capacity, scheduler: scheduler, EqualityComparer<int>.Default, LfuBufferSize.Default(concurrencyLevel: tc, capacity: capacity)), tc);
+                    results[i] = MeasureThroughput(new ConcurrentLfu<int, int>(concurrencyLevel: tc, capacity: capacity, scheduler: scheduler, EqualityComparer<int>.Default), tc);
                     scheduler.Dispose();
                 }
                 avg = AverageLast(results, runs) / 1000000;

diff --git a/BitFaster.Caching.UnitTests/Buffers/StripedBufferSizeTests.cs b/BitFaster.Caching.UnitTests/Buffers/StripedBufferSizeTests.cs
diff --git a/BitFaster.Caching.UnitTests/Lfu/ConcurrentLfuBuilderTests.cs b/BitFaster.Caching.UnitTests/Lfu/ConcurrentLfuBuilderTests.cs
@@ -1,6 +1,5 @@
 using System;
 using BitFaster.Caching.Atomic;
-using BitFaster.Caching.Buffers;
 using BitFaster.Caching.Lfu;
 using BitFaster.Caching.Scheduler;
 using FluentAssertions;
@@ -53,16 +52,6 @@ public void TestComparer()
             lfu.TryGet("A", out var value).Should().BeTrue();
         }
 
-        [Fact]
-        public void TestBufferConfiguraiton()
-        {
-            ICache<string, int> lfu = new ConcurrentLfuBuilder<string, int>()
-               .WithBufferConfiguration(new LfuBufferSize(
-                    new StripedBufferSize(128, 2)
-                   ))
-               .Build();
-        }
-
         // 1
         [Fact]
         public void WithScopedValues()

diff --git a/BitFaster.Caching.UnitTests/Lfu/ConcurrentLfuTests.cs b/BitFaster.Caching.UnitTests/Lfu/ConcurrentLfuTests.cs
@@ -18,7 +18,7 @@ public class ConcurrentLfuTests
     {
         private readonly ITestOutputHelper output;
 
-        private ConcurrentLfu<int, int> cache = new ConcurrentLfu<int, int>(1, 20, new BackgroundThreadScheduler(), EqualityComparer<int>.Default, LfuBufferSize.Default(1, 128));
+        private ConcurrentLfu<int, int> cache = new ConcurrentLfu<int, int>(1, 20, new BackgroundThreadScheduler(), EqualityComparer<int>.Default);
         private ValueFactory valueFactory = new ValueFactory();
 
         public ConcurrentLfuTests(ITestOutputHelper output)
@@ -75,7 +75,7 @@ public void WhenItemsAddedExceedsCapacityItemsAreDiscarded()
         [Fact]
         public void WhenItemIsEvictedItIsDisposed()
         {
-            var dcache = new ConcurrentLfu<int, DisposableItem>(1, 20, new BackgroundThreadScheduler(), EqualityComparer<int>.Default, LfuBufferSize.Default(1, 128));
+            var dcache = new ConcurrentLfu<int, DisposableItem>(1, 20, new BackgroundThreadScheduler(), EqualityComparer<int>.Default);
             var disposables = new DisposableItem[25];
 
             for (int i = 0; i < 25; i++)
@@ -299,7 +299,7 @@ public void WriteUpdatesProtectedLruOrder()
         [Fact]
         public void WhenHitRateChangesWindowSizeIsAdapted()
         {
-            cache = new ConcurrentLfu<int, int>(1, 20, new NullScheduler(), EqualityComparer<int>.Default, LfuBufferSize.Default(1, 128));
+            cache = new ConcurrentLfu<int, int>(1, 20, new NullScheduler(), EqualityComparer<int>.Default);
 
             // First completely fill the cache, push entries into protected
             for (int i = 0; i < 20; i++)
@@ -368,13 +368,13 @@ public void WhenHitRateChangesWindowSizeIsAdapted()
         public void ReadSchedulesMaintenanceWhenBufferIsFull()
         {
             var scheduler = new TestScheduler();
-            cache = new ConcurrentLfu<int, int>(1, 20, scheduler, EqualityComparer<int>.Default, LfuBufferSize.Default(1, 128));
+            cache = new ConcurrentLfu<int, int>(1, 20, scheduler, EqualityComparer<int>.Default);
 
             cache.GetOrAdd(1, k => k);
             scheduler.RunCount.Should().Be(1);
             cache.PendingMaintenance();
 
-            for (int i = 0; i < LfuBufferSize.DefaultBufferSize; i++)
+            for (int i = 0; i < ConcurrentLfu<int, int>.DefaultBufferSize; i++)
             {
                 scheduler.RunCount.Should().Be(1);
                 cache.GetOrAdd(1, k => k);
@@ -389,30 +389,29 @@ public void ReadSchedulesMaintenanceWhenBufferIsFull()
         public void WhenReadBufferIsFullReadsAreDropped()
         {
             var scheduler = new TestScheduler();
-            cache = new ConcurrentLfu<int, int>(1, 20, scheduler, EqualityComparer<int>.Default, LfuBufferSize.Default(1, 128));
+            cache = new ConcurrentLfu<int, int>(1, 20, scheduler, EqualityComparer<int>.Default);
 
             cache.GetOrAdd(1, k => k);
             scheduler.RunCount.Should().Be(1);
             cache.PendingMaintenance();
 
-            for (int i = 0; i < LfuBufferSize.DefaultBufferSize * 2; i++)
+            for (int i = 0; i < ConcurrentLfu<int, int>.DefaultBufferSize * 2; i++)
             {
                 cache.GetOrAdd(1, k => k);
             }
 
             cache.PendingMaintenance();
 
-            cache.Metrics.Value.Hits.Should().Be(LfuBufferSize.DefaultBufferSize);
+            cache.Metrics.Value.Hits.Should().Be(ConcurrentLfu<int, int>.DefaultBufferSize);
         }
 
         [Fact]
         public void WhenWriteBufferIsFullAddDoesMaintenance()
         {
-            var bufferSize = LfuBufferSize.DefaultBufferSize;
+            var bufferSize = ConcurrentLfu<int, int>.DefaultBufferSize;
             var scheduler = new TestScheduler();
 
-            var bufferConfig = new LfuBufferSize(new StripedBufferSize(bufferSize, 1));
-            cache = new ConcurrentLfu<int, int>(1, bufferSize * 2, scheduler, EqualityComparer<int>.Default, bufferConfig);
+            cache = new ConcurrentLfu<int, int>(1, bufferSize * 2, scheduler, EqualityComparer<int>.Default);
 
             // add an item, flush write buffer
             cache.GetOrAdd(-1, k => k);
@@ -439,8 +438,7 @@ public void WhenWriteBufferIsFullUpdatesAreDropped()
             int capacity = 20;
             var bufferSize = Math.Min(BitOps.CeilingPowerOfTwo(capacity), 128);
             var scheduler = new TestScheduler();
-            var bufferConfig = new LfuBufferSize(new StripedBufferSize(bufferSize, 1));
-            cache = new ConcurrentLfu<int, int>(1, capacity, scheduler, EqualityComparer<int>.Default, bufferConfig);
+            cache = new ConcurrentLfu<int, int>(1, capacity, scheduler, EqualityComparer<int>.Default);
 
             cache.GetOrAdd(1, k => k);
             scheduler.RunCount.Should().Be(1);
@@ -572,7 +570,7 @@ public void WhenItemIsRemovedItIsRemoved()
         [Fact]
         public void WhenItemIsRemovedItIsDisposed()
         {
-            var dcache = new ConcurrentLfu<int, DisposableItem>(1, 20, new BackgroundThreadScheduler(), EqualityComparer<int>.Default, LfuBufferSize.Default(1, 128));
+            var dcache = new ConcurrentLfu<int, DisposableItem>(1, 20, new BackgroundThreadScheduler(), EqualityComparer<int>.Default);
             var disposable = new DisposableItem();
 
             dcache.GetOrAdd(1, k => disposable);
@@ -661,7 +659,7 @@ public void TrimRemovesNItems()
         public void TrimWhileItemsInWriteBufferRemovesNItems()
         {
             // null scheduler == no maintenance, all writes fit in buffer
-            cache = new ConcurrentLfu<int, int>(1, 20, new NullScheduler(), EqualityComparer<int>.Default, LfuBufferSize.Default(1, 128));
+            cache = new ConcurrentLfu<int, int>(1, 20, new NullScheduler(), EqualityComparer<int>.Default);
 
             for (int i = 0; i < 25; i++)
             {
@@ -699,7 +697,7 @@ public void VerifyHitsWithBackgroundScheduler()
         public void VerifyHitsWithThreadPoolScheduler()
         {
             // when running all tests in parallel, sample count drops significantly: set low bar for stability.
-            cache = new ConcurrentLfu<int, int>(1, 20, new ThreadPoolScheduler(), EqualityComparer<int>.Default, LfuBufferSize.Default(1, 128));
+            cache = new ConcurrentLfu<int, int>(1, 20, new ThreadPoolScheduler(), EqualityComparer<int>.Default);
             VerifyHits(iterations: 10000000, minSamples: 500000);
         }
 
@@ -709,7 +707,7 @@ public void VerifyHitsWithThreadPoolScheduler()
         [Fact]
         public void VerifyHitsWithNullScheduler()
         {
-            cache = new ConcurrentLfu<int, int>(1, 20, new NullScheduler(), EqualityComparer<int>.Default, LfuBufferSize.Default(1, 128));
+            cache = new ConcurrentLfu<int, int>(1, 20, new NullScheduler(), EqualityComparer<int>.Default);
             VerifyHits(iterations: 10000000, minSamples: -1);
         }
 
@@ -720,12 +718,12 @@ public void VerifyHitsWithNullScheduler()
         [Fact]
         public void VerifyHitsWithForegroundScheduler()
         {
-            cache = new ConcurrentLfu<int, int>(1, 20, new ForegroundScheduler(), EqualityComparer<int>.Default, LfuBufferSize.Default(1, 128));
+            cache = new ConcurrentLfu<int, int>(1, 20, new ForegroundScheduler(), EqualityComparer<int>.Default);
 
             // Note: TryAdd will drop 1 read per full read buffer, since TryAdd will return false
             // before TryScheduleDrain is called. This serves as sanity check.
             int iterations = 10000000;
-            int dropped = iterations / LfuBufferSize.DefaultBufferSize;
+            int dropped = iterations / ConcurrentLfu<int, int>.DefaultBufferSize;
 
             this.output.WriteLine($"Will drop {dropped} reads.");
 
@@ -735,8 +733,7 @@ public void VerifyHitsWithForegroundScheduler()
         [Fact]
         public void VerifyMisses()
         {
-            cache = new ConcurrentLfu<int, int>(1, 20, new BackgroundThreadScheduler(), EqualityComparer<int>.Default, 
-                new LfuBufferSize(new StripedBufferSize(1, 1)));
+            cache = new ConcurrentLfu<int, int>(1, 20, new BackgroundThreadScheduler(), EqualityComparer<int>.Default);
 
             int iterations = 100000;
             Func<int, int> func = x => x;
@@ -770,8 +767,7 @@ public void VerifyMisses()
         public async Task ThreadedVerifyMisses()
         {
             // buffer size is 1, this will cause dropped writes on some threads where the buffer is full
-            cache = new ConcurrentLfu<int, int>(1, 20, new NullScheduler(), EqualityComparer<int>.Default,
-                new LfuBufferSize(new StripedBufferSize(1, 1)));
+            cache = new ConcurrentLfu<int, int>(1, 20, new NullScheduler(), EqualityComparer<int>.Default);
 
             int threads = 4;
             int iterations = 100000;

diff --git a/BitFaster.Caching.UnitTests/Lfu/LfuBufferSizeTests.cs b/BitFaster.Caching.UnitTests/Lfu/LfuBufferSizeTests.cs
diff --git a/BitFaster.Caching/Buffers/StripedBufferSize.cs b/BitFaster.Caching/Buffers/StripedBufferSize.cs