Add a benchmark for SKData

benchmarks/SkiaSharp.Benchmarks/Benchmarks/SKData/CreateFromStream.cs

@@ -0,0 +1,106 @@
+using System;
+using System.Buffers;
+using System.IO;
+using BenchmarkDotNet.Attributes;
+using BenchmarkDotNet.Diagnostics.Windows.Configs;
+using BenchmarkDotNet.Jobs;
+
+namespace SkiaSharp.Benchmarks;
+
+[EtwProfiler]
+// [NativeMemoryProfiler]
+[MemoryDiagnoser]
+// [SimpleJob(RuntimeMoniker.Mono)]
+// [SimpleJob(RuntimeMoniker.Net472)]
+// [SimpleJob(RuntimeMoniker.NetCoreApp31)]
+[SimpleJob(RuntimeMoniker.Net60)]
+public class SKDataCreateFromStream
+{
+	private int iterations;
+
+	private byte[] data;
+
+	private Stream seekable;
+	private Stream nonseekable;
+	private byte[] buffer;
+
+	[Params(1, 100, 1_000, 10_000)]
+	public int SizeKB;
+
+	[GlobalSetup]
+	public void GlobalSetup()
+	{
+		data = new byte[SizeKB * 1024];
+		var rnd = new Random();
+		rnd.NextBytes(data);
+
+		seekable = new MemoryStream(data);
+		nonseekable = new NonSeekableReadOnlyStream(seekable);
+
+		buffer = ArrayPool<byte>.Shared.Rent(SKData.CopyBufferSize);
+
+		iterations = 100_000 / SizeKB;
+
+		// init skiasharp static things
+		SKObject.GetInstance<SKObject>(IntPtr.Zero, out _);
+	}
+
+	[GlobalCleanup]
+	public void GlobalCleanup()
+	{
+		nonseekable.Dispose();
+		seekable.Dispose();
+
+		data = null;
+
+		ArrayPool<byte>.Shared.Return(buffer);
+	}
+
+	[Benchmark]
+	public void Seekable()
+	{
+		for (var i = 0; i < iterations; i++)
+		{
+			seekable.Position = 0;
+			var skdata = SKData.Create(seekable);
+			skdata.Dispose();
+		}
+	}
+
+	[Benchmark]
+	public void NonSeekable()
+	{
+		for (var i = 0; i < iterations; i++)
+		{
+			seekable.Position = 0;
+			var skdata = SKData.Create(nonseekable);
+			skdata.Dispose();
+		}
+	}
+
+	[Benchmark]
+	public unsafe void PInvoke()
+	{
+		for (var i = 0; i < iterations; i++)
+		{
+			seekable.Position = 0;
+			fixed (byte* ptr = buffer)
+			{
+				var memory = SkiaApi.sk_dynamicmemorywstream_new();
+
+				int len;
+				while ((len = nonseekable.Read(buffer, 0, buffer.Length)) > 0)
+				{
+					SkiaApi.sk_wstream_write(memory, ptr, (IntPtr)len);
+				}
+				SkiaApi.sk_wstream_flush(memory);
+
+				var skdata = SkiaApi.sk_dynamicmemorywstream_detach_as_data(memory);
+
+				SkiaApi.sk_dynamicmemorywstream_destroy(memory);
+
+				SkiaApi.sk_data_unref(skdata);
+			}
+		}
+	}
+}

benchmarks/SkiaSharp.Benchmarks/Program.cs

@@ -6,6 +6,6 @@ public class Program
 {
 	public static void Main(string[] args)
 	{
-		var summary = BenchmarkRunner.Run<Benchmark>();
+		var summary = BenchmarkRunner.Run<SKDataCreateFromStream>();
 	}
 }