Quote Originally Posted by THRESHE View Post
The use of CPU on my machine is about 50 percent !
Do you have any "busy wait" loops in your code? Or timers with short timeouts?

Quote Originally Posted by THRESHE View Post
And the use of memory is constantly growing
You might have a memory leak. You can use valgrind find it, but I'm not sure how usable it is under Mac OS. There might be some similar tools for windows, but unfortunately I don't know any of them.

You can also look for leaks yourself by checking whether you delete all objects created using new operator. Remember that Qt will delete QObjects only when you delete their parent.