问题描述
我需要在单独的线程中异步运行该函数,我使用 QtConcurrent :: run
测试 windows 时一切正常,但是一旦我在 linux 上运行相同的代码,它就开始同步工作。使用 qt4.8 和 c++98 :c
可测试代码:
void myRunFunction(QString name)
{
for(int i = 0; i <= 1000; i++)
qDebug() << name << " " << i << "from" << QThread::currentThread();
}
int main(int argc,char *argv[])
{
QCoreApplication a(argc,argv);
QFuture<void> t1 = QtConcurrent::run(myRunFunction,QString("A"));
QFuture<void> t2 = QtConcurrent::run(myRunFunction,QString("B"));
QFuture<void> t3 = QtConcurrent::run(myRunFunction,QString("C"));
t1.waitForFinished();
t2.waitForFinished();
t3.waitForFinished();
return a.exec();
}
我在控制台中得到的:
"A" 0 from QThread (0x11a78f8,name = "Thread (pooled)")
...
"A" 1000 from QThread (0x11a78f8,name = "Thread (pooled)")
after
"B" 0 from QThread (0x11a78f8,name = "Thread (pooled)")
...
"B" 1000 from QThread (0x11a78f8,name = "Thread (pooled)")
etc
告诉我如何解决这个问题,或者你还能尝试什么?我想尝试 QtConcurrent::run(QThreadPool *pool,Function function,...) 但 qt4.8 没有
解决方法
根据评论,由于对 VM 施加的限制,全局 QThreadPool
实例中的线程数似乎默认限制为单个线程。
要解决这个问题,您可以简单地使用...显式设置线程数
QThreadPool::globalInstance()->setMaxThreadCount(4);