>>>>> On Mon, 25 Jan 2021 12:51:04 -0500, Greg Klanderman <gak@klanderman.net> said:

    Greg> My biggest concern now with fully transitioning, other than a lot more
    Greg> time, is how slow it is over ssh forwarded X11.  As I said xemacs is
    Greg> perfectly snappy, but Emacs is taking sometimes 30-60+ sec just to
    Greg> create a new frame.

Does the attached patch improve frame creation?

    Greg> I turned off tooltips which seemed to be causing much of the latency
    Greg> issues, then it seemed that toolbars & menubars were the issue because
    Greg> after dragging another window over an Emacs frame, everything would
    Greg> redraw immediately but the menubars and toolbars, which could again
    Greg> take 30-60+ seconds with Emacs being essentially frozen to input.
    Greg> Switching gtk to lucid (Debian testing) did not make appreciable
    Greg> difference.

    Greg> I've now noticed that the problem only occurs when a frame of
    Greg> an Emacs is dragged over another frame of the same Emacs, so I suspect
    Greg> some problem with the event handling loop.  I will submit a bug
    Greg> report; this is perfectly reproducible with emacs -Q after ssh'ing
    Greg> from my work laptop (on home network) to my work desktop (in office
    Greg> 30mi away) and then back to my personal home desktop, even with
    Greg> tooltips/tool bars/menu bars/scroll bars off.

Which X server are you using? I donʼt see this at all (but admittedly
the two machines in question are a meter apart)