.NET 中最快的 GZIP 解压缩库 [关闭]

Question

哪个 .NET 库具有最快的解压缩性能（就吞吐量而言）？

那里有很多图书馆...

• GZipStream
• DotNetZip
• Xceed Zip for .NET
• SevenZipLib
• SharpZipLib | community sponsor of Xceed Zip for .NET

...我希望还有更多我没有列出。

有人看过这些 GZIP 库的吞吐量性能基准吗？我对解压缩吞吐量感兴趣，但我也想查看压缩结果。

Answer 1

我发现 Microsoft 的 GZipStream 实现无法读取某些 gzip 文件的问题，因此我一直在测试一些库。

这是我为您调整的基本测试，供您运行、调整和决定：

using System;
using System.Diagnostics;
using System.IO;
using System.IO.Compression;
using NUnit.Framework;
using Ionic.Zlib;
using ICSharpCode.SharpZipLib.GZip;

namespace ZipTests
{
    [TestFixture]
    public class ZipTests
    {
        MemoryStream input, compressed, decompressed;
        Stream compressor;
        int inputSize;
        Stopwatch timer;

        public ZipTests()
        {
            string testFile = "TestFile.pdf";
            using(var file = File.OpenRead(testFile))
            {
                inputSize = (int)file.Length;
                Console.WriteLine("Reading " + inputSize + " from " + testFile);
                var ms = new MemoryStream(inputSize);
                file.Read(ms.GetBuffer(), 0, inputSize);
                ms.Position = 0;
                input = ms;
            }
            compressed = new MemoryStream();
        }

        void StartCompression()
        {
            Console.WriteLine("Using " + compressor.GetType() + ":");
            GC.Collect(2, GCCollectionMode.Forced); // Start fresh
            timer = Stopwatch.StartNew();
        }

        public void EndCompression()
        {
            timer.Stop();
            Console.WriteLine("  took " + timer.Elapsed
                + " to compress " + inputSize.ToString("#,0") + " bytes into "
                + compressed.Length.ToString("#,0"));
            decompressed = new MemoryStream(inputSize);
            compressed.Position = 0; // Rewind!
            timer.Restart();
        }

        public void AfterDecompression()
        {
            timer.Stop();
            Console.WriteLine("  then " + timer.Elapsed + " to decompress.");
            Assert.AreEqual(inputSize, decompressed.Length);
            Assert.AreEqual(input.GetBuffer(), decompressed.GetBuffer());
            input.Dispose();
            compressed.Dispose();
            decompressed.Dispose();
        }

        [Test]
        public void TestGZipStream()
        {
            compressor = new System.IO.Compression.GZipStream(compressed, System.IO.Compression.CompressionMode.Compress, true);
            StartCompression();
            compressor.Write(input.GetBuffer(), 0, inputSize);
            compressor.Close();

            EndCompression();

            var decompressor = new System.IO.Compression.GZipStream(compressed, System.IO.Compression.CompressionMode.Decompress, true);
            decompressor.CopyTo(decompressed);

            AfterDecompression();
        }

        [Test]
        public void TestDotNetZip()
        {
            compressor = new Ionic.Zlib.GZipStream(compressed, Ionic.Zlib.CompressionMode.Compress, true);
            StartCompression();
            compressor.Write(input.GetBuffer(), 0, inputSize);
            compressor.Close();

            EndCompression();

            var decompressor = new Ionic.Zlib.GZipStream(compressed,
                                    Ionic.Zlib.CompressionMode.Decompress, true);
            decompressor.CopyTo(decompressed);

            AfterDecompression();
        }

        [Test]
        public void TestSharpZlib()
        {
            compressor = new ICSharpCode.SharpZipLib.GZip.GZipOutputStream(compressed)
            { IsStreamOwner = false };
            StartCompression();
            compressor.Write(input.GetBuffer(), 0, inputSize);
            compressor.Close();

            EndCompression();

            var decompressor = new ICSharpCode.SharpZipLib.GZip.GZipInputStream(compressed);
            decompressor.CopyTo(decompressed);

            AfterDecompression();
        }

        static void Main()
        {
            Console.WriteLine("Running CLR version " + Environment.Version +
                " on " + Environment.OSVersion);
            Assert.AreEqual(1,1); // Preload NUnit
            new ZipTests().TestGZipStream();
            new ZipTests().TestDotNetZip();
            new ZipTests().TestSharpZlib();
        }
    }
}

而结果在我目前正在运行的系统中（Linux上的Mono），如下：

Running Mono CLR version 4.0.30319.1 on Unix 3.2.0.29
Reading 37711561 from /home/agustin/Incoming/ZipTests/TestFile.pdf
Using System.IO.Compression.GZipStream:
  took 00:00:03.3058572 to compress 37,711,561 bytes into 33,438,894
  then 00:00:00.5331546 to decompress.
Reading 37711561 from /home/agustin/Incoming/ZipTests/TestFile.pdf
Using Ionic.Zlib.GZipStream:
  took 00:00:08.9531478 to compress 37,711,561 bytes into 33,437,891
  then 00:00:01.8047543 to decompress.
Reading 37711561 from /home/agustin/Incoming/ZipTests/TestFile.pdf
Using ICSharpCode.SharpZipLib.GZip.GZipOutputStream:
  took 00:00:07.4982231 to compress 37,711,561 bytes into 33,431,962
  then 00:00:02.4157496 to decompress.

请注意，这是 Mono 的 GZIP，Microsoft 的版本会给出自己的结果（正如我提到的，只是无法处理你给它的任何 gzip）

这是我在 Windows 系统上得到的：

Running CLR version 4.0.30319.1 on Microsoft Windows NT 5.1.2600 Service Pack 3
Reading 37711561 from TestFile.pdf
Using System.IO.Compression.GZipStream:
  took 00:00:03.3557061 to compress 37.711.561 bytes into 36.228.969
  then 00:00:00.7079438 to decompress.
Reading 37711561 from TestFile.pdf
Using Ionic.Zlib.GZipStream:
  took 00:00:23.4180958 to compress 37.711.561 bytes into 33.437.891
  then 00:00:03.5955664 to decompress.
Reading 37711561 from TestFile.pdf
Using ICSharpCode.SharpZipLib.GZip.GZipOutputStream:
  took 00:00:09.9157130 to compress 37.711.561 bytes into 33.431.962
  then 00:00:03.0983499 to decompress.

添加更多测试很容易......

Answer 2

压缩性能基准因被压缩流的大小和精确内容而异。如果这对您来说是一个特别重要的性能瓶颈，那么值得您花时间使用每个库编写示例应用程序并使用您的真实文件运行测试。

Answer 3

对于非常大的文件，SevenZipLib 的性能很好，但我使用的是原生 7zip 格式和高度可压缩的内容。如果您使用的内容压缩率不高，那么与您可以为这些库找到的一些基准相比，您的吞吐量会有很大差异。