gui responsiveness

[Scott Christley]

Greetings,

I'm working on an application which has a background thread performing 
some extensive operations.  What I am noticing is that the gui is 
fairly unresponsive; this is presumably because my background thread is 
eating up a lot of cpu time.  I cannot slow down my background thread 
because I really do need to do as many computations as possible, but as 
soon as a user event comes in, I want the gui to respond immediately.

* I've tried setting the thread priority but this doesn't seem to 
affect anything on my system (redhat 9.0).

* Maybe my background thread can check to see if there are any gui 
events in the queue, if yes then it can pause momentarily until the 
queue is freed up?

* Or maybe there is some way for my background thread to listen on the 
incoming user events and perform the same sort of pause scenario?

One behaviour that I'm seeing is that I will click (mouse up and down) 
a menu item, then move the cursor over another menu item.  The action 
will be called for the later menu item and not for the original one 
where I did the mouse click.

I don't think that the X server itself is overloaded because I'm able 
to switch between windows and use those windows (like emacs) and have 
them be responsive.

Anybody have any ideas?

thanks
Scott