ConcurrentQueue 128-byte cache line (#22724)

ConcurrentQueue 128-byte cache line
dotnet · Sep 17, 2017 · 9c468a0 · 9c468a0
1 parent f77a663
commit 9c468a0
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Showing 2 changed files with 4 additions and 4 deletions.
diff --git a/src/System.Collections.Concurrent/src/System/Collections/Concurrent/ConcurrentQueue.cs b/src/System.Collections.Concurrent/src/System/Collections/Concurrent/ConcurrentQueue.cs
@@ -1112,10 +1112,10 @@ internal struct Slot
 
     /// <summary>Padded head and tail indices, to avoid false sharing between producers and consumers.</summary>
     [DebuggerDisplay("Head = {Head}, Tail = {Tail}")]
-    [StructLayout(LayoutKind.Explicit, Size = 192)] // padding before/between/after fields based on typical cache line size of 64
+    [StructLayout(LayoutKind.Explicit, Size = 384)] // padding before/between/after fields based on worst case cache line size of 128
     internal struct PaddedHeadAndTail
     {
-        [FieldOffset(64)] public int Head;
-        [FieldOffset(128)] public int Tail;
+        [FieldOffset(128)] public int Head;
+        [FieldOffset(256)] public int Tail;
     }
 }
diff --git a/src/System.Threading.Tasks.Dataflow/src/Internal/ProducerConsumerQueues.cs b/src/System.Threading.Tasks.Dataflow/src/Internal/ProducerConsumerQueues.cs
@@ -551,7 +551,7 @@ static class PaddingHelpers
     }
 
     /// <summary>Padding structure used to minimize false sharing in SingleProducerSingleConsumerQueue{T}.</summary>
-    [StructLayout(LayoutKind.Explicit, Size = PaddingHelpers.CACHE_LINE_SIZE - sizeof(Int32))] // Based on common case of 64-byte cache lines
+    [StructLayout(LayoutKind.Explicit, Size = PaddingHelpers.CACHE_LINE_SIZE - sizeof(Int32))]
     struct PaddingFor32
     {
     }