Sebastian Wålinder <s.walin...@gmail.com> writes: > I have massive org-mode file with thousands of SRC blocks. > > As the file grew, I started to get very poor performance, but setting > `org-fold-core--ignore-modifications` to `t` solved it. > > However, I still get very poor performance when a lot of folded headings are > in view. It gets slower as headings with more text hidden inside its fold > come into view. > > I have tried running the profiler to find out what the issue is, but no > matter how laggy Emacs gets, the profiler records practically no CPU samples > or memory usage. > > When the massive org buffer is in view and showing large folded headlines, > any command run is very slow, even if the action is performed in another > buffer entirely. It returns to normal when no window is showing the headings, > as well as when I bring the folded headings out of view or unfold them.
This is expected. The problem is with Emacs redisplay engine that cannot easily handle large number of text properties - on C level. You can try to set `org-fold-core--optimise-for-huge-buffers' to '(grab-invisible) locally in the problematic Org file - it should reduce the number of text properties used at the cost of not preserving folded drawers when folding the containing heading. -- Ihor Radchenko // yantar92, Org mode contributor, Learn more about Org mode at <https://orgmode.org/>. Support Org development at <https://liberapay.com/org-mode>, or support my work at <https://liberapay.com/yantar92>
