Slow scrolling seemly caused by ido-completing-read
ccakes opened this issue · 2 comments
I'm on Emacs 28 master with native-comp so this might be a bit of a bleeding edge case but worth asking about.
Scrolling in some buffers feels extremely slow and pegs the CPU, but others is fine. org-mode is fine, go-mode with lsp-mode and gopls is very sluggish. Enabling the profiler and just scrolling ~50 lines down an open buffer gives me this:
Samples % Function
393 75% - command-execute
393 75% - call-interactively
393 75% - apply
393 75% - call-interactively@ido-cr+-record-current-command
393 75% - #<subr call-interactively>
393 75% - funcall-interactively
389 74% - amx
389 74% - amx-read-and-run
377 72% - amx-completing-read
377 72% - amx-completing-read-auto
377 72% - amx-completing-read
376 72% - amx-completing-read-ido
376 72% - ido-completing-read+
373 71% - ido-completing-read
373 71% - apply
373 71% - ido-completing-read@ido-cr+-replace
373 71% - #<subr ido-completing-read>
373 71% - ido-read-internal
373 71% - apply
373 71% - ad-Advice-ido-read-internal
373 71% - #<subr ido-read-internal>
318 61% - read-from-minibuffer
70 13% + timer-event-handler
51 9% + ido-exhibit
4 0% + redisplay_internal (C function)
1 0% ido-cr+-schedule-dynamic-collection-update
2 0% + #<compiled 0x189a5f324cedffe8>
7 1% + amx-augment-commands-with-keybinds
3 0% + execute-extended-command
1 0% + amx-make-keybind-hash
4 0% + evil-next-line
47 9% + redisplay_internal (C function)
45 8% + ...
35 6% + lsp-ui-doc--make-request
Any ideas on where I can start digging? It feels like a side effect since I can't think why completing-read would even be being triggered on a next-line but 🤷
Hmm, the presence of amx in the call stack implies that you might be capturing a lot of work that Emacs is doing while executing M-x. I'm guessing you did something like M-x profiler-stop at the end? Can you instead try executing something like this using M-x eval-expression? That way, there should be no usage of M-x during profiling.
(progn
(profiler-start 'cpu)
(dotimes (x 100)
(next-line)
(redisplay))
(profiler-stop)
(profiler-report))Alternatively, you could stick this code in a command and run it directly with M-x. Here's what I get when I run it:
- command-execute 593 96%
- call-interactively 593 96%
- apply 593 96%
- call-interactively@ido-cr+-record-current-command 593 96%
- apply 593 96%
- #<subr call-interactively> 593 96%
- funcall-interactively 593 96%
- eval-expression 593 96%
- apply 593 96%
- #<compiled 0x4429db95> 593 96%
- eval 593 96%
- progn 593 96%
- let 593 96%
- while 593 96%
- let 593 96%
- next-line 147 23%
- apply 147 23%
- ad-Advice-next-line 147 23%
- #<compiled 0x44271f9d> 147 23%
- line-move 147 23%
- line-move-visual 141 22%
+ posn-at-point 5 0%
+ redisplay 67 10%
- ... 21 3%
Automatic GC 21 3%
🤦
Thanks for the tip - looks like it's definitely unrelated to this package. Thanks for the super quick help and for pointing me in the right direction! 😊
1444 100% - command-execute
1444 100% - call-interactively
1444 100% - apply
1444 100% - call-interactively@ido-cr+-record-current-command
1444 100% - #<subr call-interactively>
1444 100% - funcall-interactively
1444 100% - eval-expression
1444 100% - apply
1444 100% - #<subr eval-expression>
1444 100% - progn
1441 99% - let
1441 99% - while
1441 99% - let
1057 73% - redisplay
16 1% - timer-event-handler
16 1% - apply
15 1% - auto-revert-buffers
15 1% - auto-revert-buffer
15 1% - auto-revert-handler
15 1% - vc-refresh-state
15 1% - apply
15 1% - #<compiled -0x29de2f0d28e0987>
15 1% - apply
15 1% - #<subr vc-refresh-state>
9 0% - vc-backend
9 0% + vc-registered
3 0% + vc-mode-line
2 0% + vc-call-backend
10 0% + redisplay_internal (C function)
296 20% + next-line
3 0% + profiler-start
0 0% + ...