On Mon, 2 Sep 2024, at 13:05, Eli Zaretskii wrote: >> Date: Mon, 02 Sep 2024 10:18:03 +0100 >> From: "Stephane Travostino" <s...@combo.cc> >> >> Heavy operations, such as scrolling back and forth in a buffer, are >> noticeably laggier, for lack of better word, in the PGTK/Wayland version >> than the X11, both tested on KDE in Wayland mode. >> >> Affects both 29.2 and the latest HEAD compiled a few days ago. >> >> I am unsure whether it is a KDE or Emacs problem. >> >> Running on an AMD RX 6800 XT graphics card on a HiDPI 4k screen at 2x >> scaling. > > AFAIU, this is a problem with GTK input methods. From PROBLEMS: > > *** Emacs built with GTK lags in its response to keyboard input. > This can happen when input methods are used. It happens because Emacs > behaves in an unconventional way with respect to GTK input methods: it > registers to receive keyboard input as unprocessed key events with > metadata (as opposed to receiving them as text strings). Most GTK > programs use the latter approach, so some modern input methods have > bugs and misbehave when faced with the way Emacs does it. > > A workaround is to set GTK_IM_MODULE=none in the environment, or maybe > find a different input method without these problems.
Thank you, though without more scientific methods of measuring latency I can't tell if that helps or not. I noticed I had pixel precision scrolling mode on and that contributed a large part to that feeling of lag compared to other programs. If Firefox is able to smooth scroll at 60 Hz, I would say empirically Emacs PGTK would scroll at 15 Hz, making navigation in the buffer a choppy affair.
