// 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();
/// The reason for a BufferAllocated event.
internal enum BufferAllocatedReason : int
{
/// The pool is allocating a buffer to be pooled in a bucket.
Pooled,
/// The requested buffer size was too large to be pooled.
OverMaximumSize,
/// The pool has already allocated for pooling as many buffers of a particular size as it's allowed.
PoolExhausted
}
///
/// 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).
///
[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);
}
///
/// 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.
///
[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);
}
///
/// 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.
///
[Event(3, Level = EventLevel.Verbose)]
internal void BufferReturned(int bufferId, int bufferSize, int poolId) => WriteEvent(3, bufferId, bufferSize, poolId);
}
}