Add beatmap parsing as sample benchmark.

osu.Game.Benchmarks/BenchmarkBeatmapParsing.cs

@@ -0,0 +1,37 @@
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using System.IO;
+using BenchmarkDotNet.Attributes;
+using osu.Framework.IO.Stores;
+using osu.Game.Beatmaps;
+using osu.Game.Beatmaps.Formats;
+using osu.Game.IO;
+using osu.Game.IO.Archives;
+using osu.Game.Resources;
+
+namespace osu.Game.Benchmarks
+{
+    public class BenchmarkBeatmapParsing : BenchmarkTest
+    {
+        private readonly MemoryStream beatmapStream = new MemoryStream();
+
+        public override void SetUp()
+        {
+            using (var resources = new DllResourceStore(OsuResources.ResourceAssembly))
+            using (var archive = resources.GetStream("Beatmaps/241526 Soleily - Renatus.osz"))
+            using (var reader = new ZipArchiveReader(archive))
+                reader.GetStream("Soleily - Renatus (Gamu) [Insane].osu").CopyTo(beatmapStream);
+        }
+
+        [Benchmark]
+        public Beatmap BenchmarkBundledBeatmap()
+        {
+            beatmapStream.Seek(0, SeekOrigin.Begin);
+            var reader = new LineBufferedReader(beatmapStream); // no disposal
+
+            var decoder = Decoder.GetDecoder<Beatmap>(reader);
+            return decoder.Decode(reader);
+        }
+    }
+}