How can I manage quantity threads making by QThreadPool?

[AlekseyB]

I have i3-4130 processor and due to hyper- threading IdealThreadCount in my case is 4. I tried use:

setMaxThreadCount(2);
or
Tasks.reserveThread();
Tasks.reserveThread();

but it doesn't work: program use all 4 threads.
How can I set only 2 thread?

[aha_1980]

Hi @AlekseyB,

How can I set only 2 thread?

According to documentation it should work with setMaxThreadCount(2)

Which version of Qt are you using? And which platform?

[jsulm]

@AlekseyB said in How can I manage quantity threads making by QThreadPool?:

setMaxThreadCount(2);

Can you show how you call it?

[AlekseyB]

Which version of Qt are you using? And which platform?
x64-5.10.0

Can you show how you call it?

class TaskManager: public QThreadPool
    {
        QThreadPool* ThreadPool;

    public:
        TaskManager() {ThreadPool = QThreadPool::globalInstance();}

        void addTask(QRunnable* const Task_, cint Priority_ = 0) {ThreadPool->start(Task_, Priority_);}

        void WaitForFinish() {while(!ThreadPool->waitForDone(500)) QApplication::processEvents();}
    };
...
TaskManager Tasks;

Tasks->setMaxThreadCount(2);
//or
Tasks.reserveThread();
Tasks.reserveThread();

[SGaist]

Hi,

You are creating a new QThreadPool in which you get the global instance. Then you modify your custom thread pool but still use the unmodified global instance to start your work.

[AlekseyB]

@SGaist
Thenk you, now work!