Re: UI display appears sluggish in multi-threaded app
On Jun 19, 3:48 am, Woody <ols6...@sbcglobal.net> wrote:
I have an MFC app which does very compute-intensive calculations. It
is multi-threaded, with the UI in the main thread, and several worker
threads which do the calculating. The UI thread does nothing except
report on the status of the workers. It gets this status by accessing
shared memory.
The UI thread is supposed to update some numbers on the display every
few seconds, so there is a timer to redraw the screen. With all the
threads at default priorities, what happens is that the screen update
only occurs after a long delay, 30 sec or more.
How should I arrange things so the UI thread displays when the timer
tells it to (every 3-5 sec), yet does not use any CPU cycles at other
times. Keyboard/mouse response is secondary, although if it doesn't
"cost" anything, it would be a plus.
The GUI thread does not normally use any CPU cycles except while it is
processing a message. You should not have to do anything special to
get this behavior. Your message handlers are supposed to return to MFC
quickly. Are you polling something? One suspects you are executing
some kind of long loop in the GUI thread. You would have to show how
you handle the timer and the painting for further diagnosis.