The efficiency of QList append method in QT6 is much lower than that in QT5

#include <QCoreApplication>
#include "QList"

struct TradeData{
 QDateTime beginDate;
 QString exchangeID;
 double beginPrice=0;
 double endPrice=0;
 int num=0; 
};

int main(int argc, char *argv[])
{
 QCoreApplication a(argc, argv); 
 qint64 start=QDateTime::currentMSecsSinceEpoch();
 TradeData td;
 td.begindate=QDateTime::currentDateTime();
 QList<TradeData>temp;
 for(int i=0;i<1000000;++i){
 temp.push_back(td);
 }
 qint64 interval=QDateTime::currentMSecsSinceEpoch()-start;
 std::cout<<"time:"<<interval<<std::endl;

return a.exec();
}