QApplication init very slow

huajin

my software startup is very slow, and i found QApplication init is very slow.
how can i upgrade the startup speed??

sierdzio

Make sure you are using newest Qt version available. QApplication init was slow in Qt 5.0 and Qt 5.1, it has been fixed in Qt 5.2.

huajin

yes, i am ture it is qt5.2 + mingw32, but my software run in CD. when the cd put into computer, statup my software first, it is very slow, about 1-2 m. next times it is very quickly about 1-2 sec. i donot know how to do??can you help me

huajin

i am waiting online. it is very important for me.
[quote author="sierdzio" date="1390742972"]Make sure you are using newest Qt version available. QApplication init was slow in Qt 5.0 and Qt 5.1, it has been fixed in Qt 5.2.[/quote]

sierdzio

Your OS needs do load the DLLs before it can start the application, I suspect that is the problem. There is little you can do about it, apart from maybe using a faster CD drive.

I might be wrong, though, there may be some nice solution waiting for you. I just don't know it :)

JKSH

Hi,

Here is a way to check if your CD player is the problem: Copy everything from your CD into a folder on your desktop. Run your program from this folder.

Is it much faster than running from the CD?

huajin

i have tried.

Run my program on desktop, it is very fast....

i write a test program, just only display a button, copy it to CD and run it, it also very slow.

so i think QApplication init is result.

Test program like this:

QApplication a(argv, argc);
QPushButton btn("test");
btn.show();
a.exec();

[quote author="JKSH" date="1390835206"]Hi,

Here is a way to check if your CD player is the problem: Copy everything from your CD into a folder on your desktop. Run your program from this folder.

Is it much faster than running from the CD?[/quote]

JKSH

[quote author="huajin" date="1390835541"]Run my program on desktop, it is very fast....

i write a test program, just only display a button, copy it to CD and run it, it also very slow.[/quote]Then QApplication init is fast, but your CD drive is slow.

huajin

my CD drive is fast.

i copy some VB and MFC program to CD and run it, it very fast...

[quote author="JKSH" date="1390835838"][quote author="huajin" date="1390835541"]Run my program on desktop, it is very fast....

i write a test program, just only display a button, copy it to CD and run it, it also very slow.[/quote]Then QApplication init is fast, but your CD drive is slow.[/quote]