Re: Display slowness that is painful

[Richard M. Stallman]

    Well, it generates the desired_matrix for all windows/frames
    before it decides what parts of the display should be updated
    by comparing to the current_matrix.  

    If generating the desired_matrix takes a long time, emacs
    doesn't update the display for a long time...

It seems surprising that generating the desired_matrix would take
a whole second on a modern computer.  Is that often the case
in your usage?