Add compression benchmarks that capture recent zlib regressions

[ericstj]

Highly compressible data

dotnet/runtime#118457 (comment) includes a comparison and sample benchmark that includes a large number of iterations of highly-compressible data. This regressed in 9.0 and was missed. We should add a benchmark to cover that.

 [Benchmark]
 public void CompressionTest()
 {
 var testData = _testData[TestFile];
 testData.CompressedStream.Position = 0;

 using (var z = new DeflateStream(testData.CompressedStream, CompressionMode.Compress, true))
 {
 for (int i = 0; i < testData.Iterations; i++)
 {
 z.Write(testData.Data);
 }
 }
 }

https://github.com/dotnet/performance/blob/main/src/benchmarks/micro/libraries/System.IO.Compression/TestData/alice29.txt should fit the bill, so simply adding some iterations to

performance/src/benchmarks/micro/libraries/System.IO.Compression/CompressionStreamPerfTestBase.cs

Lines 58 to 64 in b8a4259

	public void Compress()
	{
	CompressedFile.CompressedDataStream.Position = 0; // all benchmarks invocation reuse the same stream, we set Postion to 0 to start at the beginning
	var compressor = CreateStream(CompressedFile.CompressedDataStream, level);
	compressor.Write(CompressedFile.UncompressedData, 0, CompressedFile.UncompressedData.Length);
	}

might be enough to capture.

Heap fragmentation

dotnet/runtime#117949 addresses a case where removal of our custom allocator regressed performance on windows x64.

We were able to reproduce that with a benchmark that @stephentoub wrote:

using BenchmarkDotNet.Attributes;
using BenchmarkDotNet.Running;
using System.IO.Compression;

BenchmarkSwitcher.FromAssembly(typeof(Bench).Assembly).Run(args);

public class Bench
{
 private Barrier _barrier = new Barrier(Environment.ProcessorCount - 1);

 [Benchmark]
 public void Test()
 {
 Task.WaitAll(Enumerable
 .Range(0, _barrier.ParticipantCount)
 .Select(_ => Task.Run(() =>
 {
 _barrier.SignalAndWait();
 for (int length = 1; length < 1000; length++)
 {

 byte[] buffer = new byte[length];
 Random.Shared.NextBytes(buffer);
 using (var z = new ZLibStream(new MemoryStream(), CompressionMode.Compress))
 {
 for (int i = 0; i < 100; i++)
 {
 z.Write(buffer);
 }
 }
 }
 })).ToArray());
 }
}

Method	Runtime	Mean	Error	StdDev	Ratio	RatioSD
Test	.NET 8.0	153.2 ms	3.05 ms	8.44 ms	1.00	0.08
Test	.NET 9.0	289.5 ms	5.64 ms	8.61 ms	1.90	0.12