Imported Upstream version 2.0.0.11353upstream/2.0.0.11353

1 files changed, 78 insertions, 0 deletions

diff --git a/src/mscorlib/src/System/Buffers/ArrayPoolEventSource.cs b/src/mscorlib/src/System/Buffers/ArrayPoolEventSource.cs
new file mode 100644
index 0000000000..9482744144
--- /dev/null
+++ b/src/mscorlib/src/System/Buffers/ArrayPoolEventSource.cs
@@ -0,0 +1,78 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System.Diagnostics.Tracing;
+
+namespace System.Buffers
+{
+    [EventSource(Name = "System.Buffers.ArrayPoolEventSource")]
+    internal sealed class ArrayPoolEventSource : EventSource
+    {
+        internal readonly static ArrayPoolEventSource Log = new ArrayPoolEventSource();
+
+        /// <summary>The reason for a BufferAllocated event.</summary>
+        internal enum BufferAllocatedReason : int
+        {
+            /// <summary>The pool is allocating a buffer to be pooled in a bucket.</summary>
+            Pooled,
+            /// <summary>The requested buffer size was too large to be pooled.</summary>
+            OverMaximumSize,
+            /// <summary>The pool has already allocated for pooling as many buffers of a particular size as it's allowed.</summary>
+            PoolExhausted
+        }
+
+        /// <summary>
+        /// Event for when a buffer is rented.  This is invoked once for every successful call to Rent,
+        /// regardless of whether a buffer is allocated or a buffer is taken from the pool.  In a
+        /// perfect situation where all rented buffers are returned, we expect to see the number
+        /// of BufferRented events exactly match the number of BuferReturned events, with the number
+        /// of BufferAllocated events being less than or equal to those numbers (ideally significantly
+        /// less than).
+        /// </summary>
+        [Event(1, Level = EventLevel.Verbose)]
+        internal unsafe void BufferRented(int bufferId, int bufferSize, int poolId, int bucketId)
+        {
+            EventData* payload = stackalloc EventData[4];
+            payload[0].Size = sizeof(int);
+            payload[0].DataPointer = ((IntPtr)(&bufferId));
+            payload[1].Size = sizeof(int);
+            payload[1].DataPointer = ((IntPtr)(&bufferSize));
+            payload[2].Size = sizeof(int);
+            payload[2].DataPointer = ((IntPtr)(&poolId));
+            payload[3].Size = sizeof(int);
+            payload[3].DataPointer = ((IntPtr)(&bucketId));
+            WriteEventCore(1, 4, payload);
+        }
+
+        /// <summary>
+        /// Event for when a buffer is allocated by the pool.  In an ideal situation, the number
+        /// of BufferAllocated events is significantly smaller than the number of BufferRented and
+        /// BufferReturned events.
+        /// </summary>
+        [Event(2, Level = EventLevel.Informational)]
+        internal unsafe void BufferAllocated(int bufferId, int bufferSize, int poolId, int bucketId, BufferAllocatedReason reason)
+        {
+            EventData* payload = stackalloc EventData[5];
+            payload[0].Size = sizeof(int);
+            payload[0].DataPointer = ((IntPtr)(&bufferId));
+            payload[1].Size = sizeof(int);
+            payload[1].DataPointer = ((IntPtr)(&bufferSize));
+            payload[2].Size = sizeof(int);
+            payload[2].DataPointer = ((IntPtr)(&poolId));
+            payload[3].Size = sizeof(int);
+            payload[3].DataPointer = ((IntPtr)(&bucketId));
+            payload[4].Size = sizeof(BufferAllocatedReason);
+            payload[4].DataPointer = ((IntPtr)(&reason));
+            WriteEventCore(2, 5, payload);
+        }
+
+        /// <summary>
+        /// Event raised when a buffer is returned to the pool.  This event is raised regardless of whether
+        /// the returned buffer is stored or dropped.  In an ideal situation, the number of BufferReturned
+        /// events exactly matches the number of BufferRented events.
+        /// </summary>
+        [Event(3, Level = EventLevel.Verbose)]
+        internal void BufferReturned(int bufferId, int bufferSize, int poolId) => WriteEvent(3, bufferId, bufferSize, poolId);
+    }
+}