Re: Redisplay slower in Emacs 28 than Emacs 27

[Lars Ingebrigtsen]

Lars Ingebrigtsen <larsi@gnus.org> writes:

> Anyway, this has reminded me of something I've wondered about before:
> Why doesn't `create-image' stick a :hash element into the spec so that
> redisplay doesn't have to recompute it all the time?  Especially with
> large datap images, not having to recompute the hash when redisplaying
> must surely be a big win...

On the other hand, since we're doing the comparison with EQ, it makes
little sense to compute the hash with a function that takes string
contents into consideration.  So we would make a much simpler and faster
hash function for the image cache that just looks at object identity
(and number values) and not anything else.

-- 
(domestic pets only, the antidote for overdose, milk.)
   bloggy blog: http://lars.ingebrigtsen.no