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我们正在尝试使用 ServiceStack 包装器在 Redis 中存储一些大缓冲区（每个 8MB）。我们使用“RedisNativeClient.Set(string key, byte[] value)” API 来设置缓冲区。客户端和服务器都驻留在同一台机器上。坚持残疾人。我们目前正在使用 ServiceStack 的评估版。

问题是我们的性能很差——大约 60 MB/秒。使用一些不同的 c# 包装器（“Sider”），我们可以获得更好的性能（~400 MB/秒）。

我用于测量的代码：

 public void SimpleTest()
        {
            Stopwatch sw;
            long ms1, ms2, interval;
            int nBytesHandled = 0;
            int nBlockSizeBytes = 8000000;
            int nMaxIterations = 5;
            byte[] pBuffer = new byte[(int)(nBlockSizeBytes)];


            // Create Redis Wrapper
            ServiceStack.Redis.RedisNativeClient m_serviceStackRedisClient = new ServiceStack.Redis.RedisNativeClient();

            // Clear DB
            m_serviceStackRedisClient.FlushAll();


            sw = Stopwatch.StartNew();
            ms1 = sw.ElapsedMilliseconds;
            for (int i = 0; i < nMaxIterations; i++)
            {
                m_serviceStackRedisClient.Set("eitan" + i.ToString(), pBuffer);
                nBytesHandled += nBlockSizeBytes;
            }

            ms2 = sw.ElapsedMilliseconds;
            interval = ms2 - ms1;

            // Calculate rate
            double dMBPerSEc = nBytesHandled / 1024.0 / 1024.0 / ((double)interval / 1000.0);
            Console.WriteLine("Rate {0:N4}", dMBPerSEc);
        }

可能是什么问题？

谢谢，伊坦。

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1 回答 1

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ServiceStack.Redis uses a reusable Buffer Pool to reduce memory pressure by reusing a pool of byte buffers. The size of the default byte[] buffer is 1450 bytes to fit within the Ethernet MTU packet size. Whilst this default configuration is optimal for the normal use-case of smaller payloads (<100k) it looks like it ends up being slower for larger payloads (>1MB+).

Based on this the ServiceStack.Redis client has now been modified so that it no longer uses the buffer pool for payloads larger than 500k which is now configurable with RedisConfig.BufferPoolMaxSize, e.g:

RedisConfig.BufferPoolMaxSize = 500000;

The default 1450 byte size of the byte[] buffer is now also configurable with: 

RedisConfig.BufferLength = 1450;

This change now improves the throughput performance of ServiceStack.Redis for larger payloads as seen in RedisBenchmarkTests suite which uses your benchmark with different payload sizes, e.g:

public void Run(string name, int nBlockSizeBytes, Action<int,byte[]> fn)
{
    Stopwatch sw;
    long ms1, ms2, interval;
    int nBytesHandled = 0;
    int nMaxIterations = 5;
    byte[] pBuffer = new byte[nBlockSizeBytes];

    // Create Redis Wrapper
    var redis = new RedisNativeClient();

    // Clear DB
    redis.FlushAll();

    sw = Stopwatch.StartNew();
    ms1 = sw.ElapsedMilliseconds;
    for (int i = 0; i < nMaxIterations; i++)
    {
        fn(i, pBuffer);
        nBytesHandled += nBlockSizeBytes;
    }

    ms2 = sw.ElapsedMilliseconds;
    interval = ms2 - ms1;

    // Calculate rate
    double dMBPerSEc = nBytesHandled / 1024.0 / 1024.0 / (interval / 1000.0);
    Console.WriteLine(name + ": Rate {0:N4}, Total: {1}ms", dMBPerSEc, ms2);
}

Results running from my MacBook Pro and redis-server running in an Ubuntu VirtualBox VM:

1K Results:

ServiceStack.Redis 1K: Rate 4.7684, Total: 1ms
Sider 1K: Rate 0.4768, Total: 10ms

10K Results:

ServiceStack.Redis 10K: Rate 47.6837, Total: 1ms
Sider 10K: Rate 4.3349, Total: 11ms

100K Results:

ServiceStack.Redis 100K: Rate 26.4910, Total: 18ms
Sider 100K: Rate 20.7321, Total: 23ms

1MB Results:

ServiceStack.Redis 1MB: Rate 103.6603, Total: 46ms
Sider 1MB: Rate 70.1231, Total: 68ms

8MB Results:

ServiceStack.Redis 8MB: Rate 77.0646, Total: 495ms
Sider 8MB: Rate 84.3960, Total: 452ms

Where the performance for of ServiceStack.Redis is faster for smaller payloads and now closer for payloads larger than 8MB.

This change is available from v4.0.41+ that's now available on MyGet.

于 2015-05-27T16:47:02.907 回答