Re: slow X11 frame creation and refresh after occlusion

[Greg Klanderman <gak@klanderman.net>]

>>>>> On February 4, 2021 Robert Pluim <rpluim@gmail.com> wrote:

>>>>> On Wed, 03 Feb 2021 16:52:15 -0500, Greg Klanderman <gak@klanderman.net> said:
>>>>> On February 1, 2021 Robert Pluim <rpluim@gmail.com> wrote:
Greg> (frame-parameter nil 'font-backend)
Greg> (xfthb x)

Greg> any suggestions for settings I can try?

>>> Configure '--with-cairo'. I'm hoping that will be more efficient in
>>> terms of loading fonts.

Greg> OK I will have a look.  Is there any way to determine if font loading
Greg> is causing significant delay?  And would that be an issue on
Greg> subsequent to the first frame on a display?

> Emacs does a bunch of font-related stuff every time you create a new
> graphical frame. You could try running emacs under 'perf' to see if it
> gives any insight.

OK I built from git, --with-cairo (interestingly configure does not
fail if you specify --with-cairo but don't have the libraries
installed) and am able to reproduce the issues I was seeing.

It looks like xterm.c has most of the X event handling, so maybe I
will try to put in some debug prints to see what's going on, or try
one of the X event tracing programs, or 'perf' next..

thanks,
Greg