in reply to Getting more of the processor time

  1. In general it would be better to drop the priority of the background task rather than increasing the priority of the foreground task.

    Perhaps the simplest way to do that would be to have the task immediately restart itself with a lower priority at startup.

  2. If the first process starts with below-normal priority, then when it starts the interactive with normal priority, it will take priority over the background process.
  3. If the Tk app is busy, it won't be responsive to its buttons.

    The best way to improve that is to run the GUI in a separate thread from the heavy processing. Best, but not simple.

  4. That's rather too open a question without knowing a lot more about your application.
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