> >> Here's one improvement. If you can get rid of the places in the GTK peers
> >> where class and method lookups are performed at runtime you'll probably
> >> have a fix. This shouldn't be a massive amount of work, just rather
> >> boring.
> >>
> >> In gcj,
> >>
> >> * Compiled java code is quite fast.
> >> * Class lookup by name is slow.
> >> * Calling JNI code from compiled java code is quite fast.
> >> * Calling compiled java code from JNI code is slow.
> >> * Exceptions are slow.
>
> > I'm testing your patch on my embedded system and now I can see that GUI
> > performance are very much better (particularly during application startup).
> >
> > Thank you so much!
> >
> > However running my test case (please see my first post) I see that CPU
> > usage is always at 100% (after the application is running),
> > so the responsiveness is still not very good.
>
> What do you expect? You're setting up a Timer with a delay of
> 0 milliseconds between events, and it's running continuously.
>
> Andrew.
>
You're right.
However I'm experiencing slowness when testing some other GUI sample
application (e.g. the test case attached at the end).
In this particular test case, the application takes a lot of time to startup
(compared to the same device, running WinCE and CrEme JVM) and during start up
the CPU usage is always at 100%.
After startup, I'v also noticed that highlighting and/or clicking a certain
number of times on buttons cause the application to hang and after that the CPU
usage is always 100%.
I'm still trying to get oprofile working on my target device to see what's
going wrong.
Thank you,
Francesco
Test case:
import javax.swing.JComponent;
import javax.swing.JFrame;
import java.awt.BorderLayout;
import javax.swing.JButton;
import javax.swing.JPanel;
import javax.swing.JTabbedPane;
public class GUITest {
public static void main(String[] args) {
JFrame frame = new JFrame();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JComponent newContentPane = new TestUI();
frame.setTitle("TestUI");
newContentPane.setOpaque(true);
frame.setContentPane(newContentPane);
frame.setBounds(10, 10, 500, 400);
frame.setVisible(true);
}
static class TestUI extends JPanel {
long startTime;
JPanel createPanel(int start) {
JPanel p = new JPanel();
p.setLayout(null);
for (int i=0; i<100; i++) {
JButton ltit = new JButton("Variable "+(i+start)+": ");
long val = System.currentTimeMillis() - startTime;
JButton lval = new JButton(""+val);
ltit.setBounds(5, 10+20*i, 150, 15);
lval.setBounds(200, 10+20*i, 150, 15);
p.add(ltit);
p.add(lval);
}
return p;
}
TestUI() {
super(new BorderLayout());
startTime = System.currentTimeMillis();
JTabbedPane p = new JTabbedPane();
for (int i=0; i<10; i++) {
JPanel page1 = createPanel(i*100+1);
p.add("P"+i, page1);
}
add(p, BorderLayout.CENTER);
}
}
}
