Re: bug-reference-prog-mode slows down CC Mode's scrolling by ~7%

[Stefan Monnier]

>> and it will probably say nil.
> That's sheer luck: it happens only when the invisible text between
> headings is longer than jit-lock-chunk-size.

That was exactly the case I was talking about.
That's why I wrote a few messages ago:

    Maybe a good way to see the waste is to measure the time for the
    initial font-lock in an outline-mode buffer where the screen is
    filled with single-line headers and everything else is hidden:
    a whole chunk will be fontified for each line, so with a single
    40-line screen you can expect to fontify 40 chunks (unless the
    hidden text between lines is smaller than the chunk size, of
    course).


-- Stefan