void tst_QThreadPool::reserveThread()
{
QFETCH(int, limit);
QThreadPool *threadpool = QThreadPool::globalInstance();
int savedLimit = threadpool->maxThreadCount();
threadpool->setMaxThreadCount(limit);
// reserve up to the limit
for (int i = 0; i < limit; ++i)
threadpool->reserveThread();
// reserveThread() should always reserve a thread, regardless of
// how many have been previously reserved
threadpool->reserveThread();
QCOMPARE(threadpool->activeThreadCount(), (limit > 0 ? limit : 0) + 1);
threadpool->reserveThread();
QCOMPARE(threadpool->activeThreadCount(), (limit > 0 ? limit : 0) + 2);
// cleanup
threadpool->releaseThread();
threadpool->releaseThread();
for (int i = 0; i < limit; ++i)
threadpool->releaseThread();
// reserving threads in children should not effect the parent
{
QThreadPool threadpool2(threadpool);
threadpool2.setMaxThreadCount(limit);
// reserve up to the limit
for (int i = 0; i < limit; ++i)
threadpool2.reserveThread();
// reserveThread() should always reserve a thread, regardless
// of how many have been previously reserved
threadpool2.reserveThread();
QCOMPARE(threadpool2.activeThreadCount(), (limit > 0 ? limit : 0) + 1);
threadpool2.reserveThread();
QCOMPARE(threadpool2.activeThreadCount(), (limit > 0 ? limit : 0) + 2);
threadpool->reserveThread();
QCOMPARE(threadpool->activeThreadCount(), 1);
threadpool->reserveThread();
QCOMPARE(threadpool->activeThreadCount(), 2);
// cleanup
threadpool2.releaseThread();
threadpool2.releaseThread();
threadpool->releaseThread();
threadpool->releaseThread();
while (threadpool2.activeThreadCount() > 0)
threadpool2.releaseThread();
}
// reset limit on global QThreadPool
threadpool->setMaxThreadCount(savedLimit);
}
void tst_QThreadPool::releaseThread()
{
QFETCH(int, limit);
QThreadPool *threadpool = QThreadPool::globalInstance();
int savedLimit = threadpool->maxThreadCount();
threadpool->setMaxThreadCount(limit);
// reserve up to the limit
for (int i = 0; i < limit; ++i)
threadpool->reserveThread();
// release should decrease the number of reserved threads
int reserved = threadpool->activeThreadCount();
while (reserved-- > 0) {
threadpool->releaseThread();
QCOMPARE(threadpool->activeThreadCount(), reserved);
}
QCOMPARE(threadpool->activeThreadCount(), 0);
// releaseThread() can release more than have been reserved
threadpool->releaseThread();
QCOMPARE(threadpool->activeThreadCount(), -1);
threadpool->reserveThread();
QCOMPARE(threadpool->activeThreadCount(), 0);
// releasing threads in children should not effect the parent
{
QThreadPool threadpool2(threadpool);
threadpool2.setMaxThreadCount(limit);
// reserve up to the limit
for (int i = 0; i < limit; ++i)
threadpool2.reserveThread();
// release should decrease the number of reserved threads
int reserved = threadpool2.activeThreadCount();
while (reserved-- > 0) {
threadpool2.releaseThread();
QCOMPARE(threadpool2.activeThreadCount(), reserved);
QCOMPARE(threadpool->activeThreadCount(), 0);
}
QCOMPARE(threadpool2.activeThreadCount(), 0);
QCOMPARE(threadpool->activeThreadCount(), 0);
// releaseThread() can release more than have been reserved
threadpool2.releaseThread();
QCOMPARE(threadpool2.activeThreadCount(), -1);
QCOMPARE(threadpool->activeThreadCount(), 0);
threadpool2.reserveThread();
QCOMPARE(threadpool2.activeThreadCount(), 0);
QCOMPARE(threadpool->activeThreadCount(), 0);
}
// reset limit on global QThreadPool
threadpool->setMaxThreadCount(savedLimit);
}
void tst_QThreadPool::setMaxThreadCountStartsAndStopsThreads()
{
class WaitingTask : public QRunnable
{
public:
QSemaphore waitForStarted, waitToFinish;
WaitingTask() { setAutoDelete(false); }
void run()
{
waitForStarted.release();
waitToFinish.acquire();
}
};
QThreadPool threadPool;
threadPool.setMaxThreadCount(1);
WaitingTask *task = new WaitingTask;
threadPool.start(task);
QVERIFY(task->waitForStarted.tryAcquire(1, 1000));
// thread limit is 1, cannot start more tasks
threadPool.start(task);
QVERIFY(!task->waitForStarted.tryAcquire(1, 1000));
// increasing the limit by 1 should start the task immediately
threadPool.setMaxThreadCount(2);
QVERIFY(task->waitForStarted.tryAcquire(1, 1000));
// ... but we still cannot start more tasks
threadPool.start(task);
QVERIFY(!task->waitForStarted.tryAcquire(1, 1000));
// increasing the limit should be able to start more than one at a time
threadPool.start(task);
threadPool.setMaxThreadCount(4);
QVERIFY(task->waitForStarted.tryAcquire(2, 1000));
// ... but we still cannot start more tasks
threadPool.start(task);
threadPool.start(task);
QVERIFY(!task->waitForStarted.tryAcquire(2, 1000));
// decreasing the thread limit should cause the active thread count to go down
threadPool.setMaxThreadCount(2);
QCOMPARE(threadPool.activeThreadCount(), 4);
task->waitToFinish.release(2);
QTest::qWait(1000);
QCOMPARE(threadPool.activeThreadCount(), 2);
// ... and we still cannot start more tasks
threadPool.start(task);
threadPool.start(task);
QVERIFY(!task->waitForStarted.tryAcquire(2, 1000));
// start all remaining tasks
threadPool.start(task);
threadPool.start(task);
threadPool.start(task);
threadPool.start(task);
threadPool.setMaxThreadCount(8);
QVERIFY(task->waitForStarted.tryAcquire(6, 1000));
task->waitToFinish.release(10);
// delete task;
}