synchronization objects for interprocess synchronization and multi-threadiing

線程間、進程間的同步是通過稱為“訊號量”signal的一類對象來實現的。下面是一個來自msdn的natice code world的列表：

 

Name	Relative speed	Cross process	Resource counting	Supported platforms
Critical Section	Fast	No	No (exclusive access)	9x/NT/CE
Mutex	Slow	Yes	No (exclusive access)	9x/NT/CE
Semaphore	Slow	Yes	Automatic	9x/NT
Event	Slow	Yes	Yes	9x/NT/CE
Metered Section	Fast	Yes	Automatic	9x/NT/CE

 Comments:

 

1. 如果是進程內同步線程，用critical section，因為他fast。

2. 如果是需要對shared resources做最大值限制，用semaphore。（msdn：A semaphore object is a synchronization object that maintains a count between zero and a specified maximum value. The count is decremented each time a thread completes a wait for the semaphore object and incremented each time a thread releases the semaphore. ）

3. interprocess同步，用mutex,sepaphore之類。

4. Event，有兩類：manuaset和autoset。可以用來精準控制線程的執行次序。

參考文章：Introduction to Multi-threaded Code