bug#61258: 29.0.60; pgtk build from git, WSLg, slow, heavy cpu use

[Eli Zaretskii]

> From: Fujii Hironori <fujii.hironori@gmail.com>
> Date: Wed, 2 Aug 2023 07:01:27 +0900
> 
> > Emacs built with pgtk. Editing in f90 mode, though I don't think this is
> > important. Display is WSLg. Severe input lag, to the point off becoming
> > unusable, gets worse with more frames (or just time?). Heavy CPU usage by
> > emacs while doing anything. Problem not seen when not built with pgtk.
> 
> I'm observing a similar high CPU usage problem with Emacs 29.1 on WSL1 and X 
> server, not with
> WSLg.
> As suggested by
> https://www.reddit.com/r/emacs/comments/urivlg/high_cpu_usage_in_wsl_with_emacs_29050/
> reverting
> https://github.com/emacs-mirror/emacs/commit/fa52782f5c4eaef7138534766dfc8a29465785b2
> solves the problem for me.

Thanks, but to do anything with this report we'd need at least to
understand what is causing the high CPU usage.  The linked Reddit post
has a profile, but only before removing those 4 lines.  Perhaps
comparing two profiles, before and after the change, while doing the
same stuff in the same build of Emacs, would give us some ideas.