Re: emacs rendering comparisson between emacs23 and emacs26.3

[Dmitry Gutov <dgutov@yandex.ru>]

On 06.04.2020 05:25, Eli Zaretskii wrote:
>>>> Certainly a lower bar than having mouse-scrolling never lock up.
>>> I'm not sure it is lower, because as I said an optimized Emacs doesn't
>>> lock up when I scroll, either with C-v or the mouse.  But the problems
>>> I described do happen in such builds.
>> It's lower because when you're typing you're usually typing something
>> meaningful (meaning limited input rate), and the beginning of the window
>> usually stays in place (which speeds up re-fontification).
>>
>> Whereas when you're scrolling, you can scroll as fast as your keyboard
>> allows you, and you're triggering fontification of a whole new
>> screen-ful every keystroke.
> And yet Emacs does cope with that "higher bar", whereas while I type I
> sometimes see unbearably slow responses.  Which in my book doesn't fit
> its being "lower bar".

At least it's lower in theory. But certain implementation approaches can 
make it more difficult.

Would I be correct to assume that you see only see this in CC Mode based 
major mode, and only when editing big enough files? Such as xdisp.c 
mentioned many times recently.