Subject: resizing emacs via remote X is horrible slow

From: Harald Dunkel <[email-masked]>
Date: Sun, 9 Apr 2023 09:33:55 +0200

Hi folks,

Using emacs 28.2 ("emacs-lucid", built on Debian Testing) via xlib
protocol on a remote site it is horrible slow on a window resize. If
it does a window refresh, shows some new text, scrolls text up or
down or whatever, then emacs is as fast as expected. Only resizing
the window sucks (sorry).

Would it be possible to optimze emacs in this respect?

If I run the same emacs in a remote xterm session, then it is 3 orders
of magnitude faster. Now the xterm is responsible for running xlib protocol, resizing the window and sending SIGWINCH to emacs. What has
xterm, that emacs doesn't have?

Even if you don't focus on remote XWindow connections, this problem
shows that there is something fishy in emacs. A local XWindow connction
via lan or AF_UNIX might benefit of an optimization as well.

Regards

Harri