On Sat, Sep 24, 2011 at 1:16 AM, Eli Zaretskii wrote: > > Date: Sat, 24 Sep 2011 00:18:00 +0800 > > From: Le Wang > > Cc: help-gnu-emacs@gnu.org > > > > > (setq-default bidi-display-reordering nil) > > > > > > > This helped me with my slow scroll issues. Holding down arrow on a fully > > maximized frame on a 1080p monitor was spiking my duo-core CPU to 20-25%. > > Scrolling text. 50% of one CPU. Just to scroll text. > > Scrolling how (by what commands)? next-line > What kind of text? What was the > major mode in that buffer? emacs-lisp large file I also use full font-lock salad colors with "Consolas" font on Windows. Also I use several minor-modes that add pre or post-command-hooks. > Some modes are more expensive in redisplay > than others. It is impossible to tell whether 50% of a core is > unreasonably high without knowing these details. > Additionally I have these scroll related settings. Some of which I added after realizing scrolling was slow, others I had previously to enable smooth scrolling. (setq hscroll-step 1 scroll-conservatively 10000 scroll-preserve-screen-position t auto-window-vscroll nil ; speedup down scroll scroll-margin 10 redisplay-dont-pause t ; this will be default in emacs24 ) > > And it would start jumping around almost right away. > > Does it behave better if you set redisplay-dont-pause to a non-nil > value? This will be the default in Emacs 24. > It's not making a noticeable difference. Although it sounds like a good idea. To be clear, I get perfectly smooth scrolling now with bidi-display-ordering set to nil. And my CPU usage doesn't exceed 12% while scrolling. So things are good now. -- Le