关于最优化读写，测试各个加锁：Lock、安全字典、信号量、ReaderWriterLock、ReaderWriterLockSlim

大家对于自身项目中都有本地缓存的逻辑，但这块的读写何种机制下哪个快，哪个慢，需要测试对比，以下测试报告，期望给大家一个借鉴，如果有更好的测试结果也欢迎大家一起讨论。

以下测试是开启10个并发任务对同一个字典进行10万次插入，就相当于100万次插入动作

TestLock //测试lock
        Time Elapsed:   1,342ms
        CPU Cycles:     56,099,316
        Gen 0:          67
        Gen 1:          1
        Gen 2:          0

TestSalfDictionary //测试线程安全字典
        Time Elapsed:   259ms
        CPU Cycles:     268,257
        Gen 0:          67
        Gen 1:          0
        Gen 2:          0

TestSemaphore //测试信号量
        Time Elapsed:   588ms
        CPU Cycles:     285,531
        Gen 0:          67
        Gen 1:          0
        Gen 2:          0

TestReaderWriterLock //测试ReaderWriterLock
        Time Elapsed:   4,576ms
        CPU Cycles:     241,155
        Gen 0:          67
        Gen 1:          0
        Gen 2:          0

TestReaderWriterLockSlim //测试ReaderWriterLockSlim
        Time Elapsed:   864ms
        CPU Cycles:     288,810
        Gen 0:          67
        Gen 1:          0
        Gen 2:          0

目前看下来安全字典的测试性能貌似最好的，ReaderWriteLock 效率最低，还不如lock，大家在今后项目中使用自己衡量一下！

关于信号量的测试代码，我贴一下，如觉得有更合理的运用它，欢迎来多多交流！

        static readonly Semaphore _semaphore = new Semaphore(10, 10);
        static readonly IDictionary<int, int> _dictionaryForSemaphore = new Dictionary<int, int>();
        static void TestSemaphore()
        {
            for (int i = 0; i < _number; i++)
            {
                _semaphore.WaitOne(100);
                Random random = new Random(int.MaxValue);
                var key = random.Next(int.MaxValue);
                if (!_dictionaryForSemaphore.ContainsKey(key))
                    _dictionaryForSemaphore.Add(key, i);
                _semaphore.Release();
            }
        }