相关疑难解决方法(0)

我写了一些代码来测试try-catch的影响,但看到了一些令人惊讶的结果.

static void Main(string[] args)
{
    Thread.CurrentThread.Priority = ThreadPriority.Highest;
    Process.GetCurrentProcess().PriorityClass = ProcessPriorityClass.RealTime;

    long start = 0, stop = 0, elapsed = 0;
    double avg = 0.0;

    long temp = Fibo(1);

    for (int i = 1; i < 100000000; i++)
    {
        start = Stopwatch.GetTimestamp();
        temp = Fibo(100);
        stop = Stopwatch.GetTimestamp();

        elapsed = stop - start;
        avg = avg + ((double)elapsed - avg) / i;
    }

    Console.WriteLine("Elapsed: " + avg);
    Console.ReadKey();
}

static long Fibo(int n)
{
    long n1 = 0, n2 …

我看到,对于使用非线程安全的对象,我们用这样的锁包装代码:

private static readonly Object obj = new Object();

lock (obj)
{
    // thread unsafe code
}

那么当多个线程访问相同的代码时会发生什么(让我们假设它在ASP.NET Web应用程序中运行).他们排队了吗？如果是这样,他们会等多久？

使用锁会对性能产生什么影响？

结果

锁定:85.3微秒

Monitor.TryEnter:11.0微秒

锁是否扩展为相同的代码？

编辑:1000次迭代的结果:锁定:103.3微秒Monitor.TryEnter:20.2微秒

代码如下.谢谢

    [Test]
    public void Lock_Performance_Test()
    {
        const int lockIterations = 100;

        Stopwatch csLock = Stopwatch.StartNew();
        for (int i = 0; i < lockIterations; )
        {
            lock (object1)
            {
                i++;
            }
        }
        csLock.Stop();

        Stopwatch csMonitor = Stopwatch.StartNew();
        for (int i = 0; i < lockIterations; )
        {
            if (Monitor.TryEnter(object1, TimeSpan.FromSeconds(10)))
            {
                try
                {
                    i++;
                }
                finally
                {
                    Monitor.Exit(object1);
                }
            }
        }
        csMonitor.Stop();

        Console.WriteLine("Lock: {0:f1} microseconds", csLock.Elapsed.Ticks / 10M);
        Console.WriteLine("Monitor.TryEnter: {0:f1} microseconds", csMonitor.Elapsed.Ticks / 10M);;
    }