Poco::ThreadPool
Poco::ThreadPool提供线程池功能,减少线程的创建和销毁所带来的开销,适合在服务器上应用。创建线程池时指定最少运行线程数和线程池的最大容量,若不指定则采用默认值,取2和16 。线程池的实现机制:有一部分线程始终处于运行状态,但阻塞在Event的wait调用上,所以处于休眠状态,开销并不大。如果我们需要一个线程来运行一段代码(在Poco中,用Runnable的子类表示一个target),则从线程池中去除一个线程,并将这段代码赋给它,并触发Event。然后线程就继续运行了。
活动图
demo
[cpp]
void ThreadPoolTest::testThreadPool()
{
ThreadPool pool(2, 3, 3);
assert (pool.allocated() == 2);
assert (pool.used() == 0);
assert (pool.capacity() == 3);
assert (pool.available() == 3);
pool.addCapacity(1);
assert (pool.allocated() == 2);
assert (pool.used() == 0);
assert (pool.capacity() == 4);
assert (pool.available() == 4);
RunnableAdapter<ThreadPoolTest> ra(*this, &ThreadPoolTest::hello);
pool.start(ra);
assert (pool.allocated() == 2);
assert (pool.used() == 1);
assert (pool.capacity() == 4);
assert (pool.available() == 3);
pool.start(ra);
assert (pool.allocated() == 2);
assert (pool.used() == 2);
assert (pool.capacity() == 4);
assert (pool.available() == 2);
pool.start(ra);
assert (pool.allocated() == 3);
assert (pool.used() == 3);
assert (pool.capacity() == 4);
assert (pool.available() == 1);
pool.start(ra);
assert (pool.allocated() == 4);
assert (pool.used() == 4);
assert (pool.capacity() == 4);
assert (pool.available() == 0);
}
补充:软件开发 , C++ ,