> > The exact same slowness problem happened just now. "M-x org-element-cache-reset" > > didn't have any effect. Nor did setting `org-element-use-cache' to nil. Again, > > killed the buffer and reopened didn't help. > It looks like the problem isn't related to the cache then. Anyway, you > could try to do some profiling (see `profiler-start'). > > > One thing I didn't do, unfortunately, was that I reset cache only for the buffer > > where the slowness manifested. I think I should try reseting cache for all the 8 > > buffers too right? > Cache is buffer dependent, so you don't need to reset cache for all of > them (though it's simply C-u M-x org-element-cache-reset). This problem happened again just now. Again, M-x org-element-cache-reset didn't help, nor did C-u M-x org-element-cache-reset. And it seemed that only typing characters were slow, took 1 or 2 seconds for a typed character to appear on the screen. Again, this happened in the big buffer that has 77,xxx lines, freshly opened. I restarted Emacs and finished `org-drill' session on 8 files before opening this big file. I then `M-x profile-start', typed a few letters and `M-x profile-report', here's the memory report: + # 11,320,032 43% + call-interactively 4,857,849 18% + # 2,170,499 8% + timer-event-handler 1,428,527 5% + # 1,299,957 5% + helm 1,058,503 4% + redisplay_internal (C function) 869,652 3% + ac-handle-post-command 695,448 2% + helm-M-x 517,012 2% + helm-check-new-input 215,112 0% + # 211,328 0% + helm-let-internal 182,580 0% + helm-read-pattern-maybe 109,907 0% + helm-process-filtered-candidate-transformer 97,992 0% + helm-get-cached-candidates 87,872 0% + cl-mapcar 82,880 0% + helm-update 81,536 0% + helm-funcall-with-source 72,380 0% + read-from-minibuffer 70,224 0% + funcall 69,721 0% + apply 34,618 0% + # 33,140 0% + helm--compute-sources 31,988 0% + yas--post-command-handler 29,288 0% + org-element--parse-to 29,184 0% + # 12,520 0% + helm-compute-matches 12,400 0% + let 12,288 0% + byte-code 9,320 0% + ac-handle-pre-command 9,298 0% + profiler-report-rerender-calltree 8,188 0% + command-execute 8,188 0% + helm-check-minibuffer-input 8,152 0% + zfill-org-paragraph-boundary 7,240 0% + helm-internal 7,000 0% + sp--self-insert-command 6,060 0% + helm-comp-read 5,200 0% + let* 5,028 0% + catch 4,204 0% + hl-paren-highlight 4,144 0% + zfill-pre-command-function 4,096 0% + save-restriction 4,096 0% + while 4,096 0% + save-excursion 4,096 0% + helm-M-x-current-mode-map-alist 3,144 0% + helm-display-buffer 2,080 0% + profiler-report-setup-buffer 1,066 0% + profiler-report 1,054 0% + org-element--cache-before-change 1,024 0% And CPU report: + ac-handle-post-command 2985 56% + timer-event-handler 1786 33% + redisplay_internal (C function) 131 2% + helm-M-x 121 2% Automatic GC 60 1% + call-interactively 42 0% + # 24 0% + # 24 0% + apply 23 0% + yas--table-all-keys 20 0% + helm-internal 12 0% + helm--compute-sources 12 0% + # 10 0% + # 8 0% + funcall 6 0% + # 4 0% + helm-update 4 0% + helm-check-new-input 4 0% + helm 4 0% + helm-process-filtered-candidate-transformer 4 0% + helm-get-candidates 3 0% + helm-let-internal 3 0% So I suspected the `auto-complete'. I tried M-x auto-complete to turn it off which worked, the typing was fast again. M-x auto-complete to turn it back on and typing became extremely slow again. Hope this will help a tiny bit. York