bug#51886: 29.0.50; pixel-scroll-mode garbage collects like crazy

bug#51886: 29.0.50; pixel-scroll-mode garbage collects like crazy

[Po Lu via Bug reports for GNU Emacs, the Swiss army knife of text editors]

Starting from `emacs -Q', do M-x pixel-scroll-mode RET, then configure
it as follows:

    (setq pixel-dead-time 0)
    (setq pixel-resolution-fine-flag 1)
    (setq garbage-collection-messages t)

Then scroll the display with the mouse wheel.  It will garbage collect
like crazy, leading to a great deal of stuttering (in emacs-28 as well).

I want to reuse most of the code in pixel-scroll.el for XInput2 pixel
scrolling, but this is holding me back, as the excessive garbage
collection makes it completely unusable.

Thanks.

In GNU Emacs 29.0.50 (build 74, x86_64-pc-linux-gnu, GTK+ Version 3.24.30, cairo version 1.17.4)
 of 2021-11-16 built on trinity
Repository revision: 9bad69e3fa83c0671322011ed4f563c0ff6d4892
Repository branch: feature/xinput2
Windowing system distributor 'The X.Org Foundation', version 11.0.12101002
System Description: Fedora 34 (Workstation Edition)

Configured using:
 'configure --with-xwidgets'

Configured features:
ACL CAIRO DBUS FREETYPE GIF GLIB GMP GNUTLS GSETTINGS HARFBUZZ JPEG JSON
LCMS2 LIBSELINUX LIBSYSTEMD LIBXML2 MODULES NOTIFY INOTIFY PDUMPER PNG
RSVG SECCOMP SOUND THREADS TIFF TOOLKIT_SCROLL_BARS WEBP X11 XDBE XIM
XPM XWIDGETS GTK3 ZLIB

Important settings:
  value of $LANG: en_GB.UTF-8
  value of $XMODIFIERS: @im=ibus
  locale-coding-system: utf-8-unix

Major mode: Lisp Interaction

Minor modes in effect:
  pixel-scroll-mode: t
  tooltip-mode: t
  global-eldoc-mode: t
  eldoc-mode: t
  show-paren-mode: t
  electric-indent-mode: t
  mouse-wheel-mode: t
  tool-bar-mode: t
  menu-bar-mode: t
  file-name-shadow-mode: t
  global-font-lock-mode: t
  font-lock-mode: t
  blink-cursor-mode: t
  auto-composition-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t
  line-number-mode: t
  indent-tabs-mode: t
  transient-mark-mode: t

Load-path shadows:
None found.

Features:
(shadow sort mail-extr emacsbug message mailcap yank-media rmc puny
dired dired-loaddefs rfc822 mml mml-sec epa derived epg rfc6068
epg-config gnus-util rmail rmail-loaddefs auth-source cl-seq eieio
eieio-core cl-macs eieio-loaddefs password-cache json map
text-property-search seq gv byte-opt bytecomp byte-compile cconv
mm-decode mm-bodies mm-encode mail-parse rfc2231 mailabbrev gmm-utils
mailheader sendmail rfc2047 rfc2045 ietf-drums mm-util mail-prsvr
mail-utils time-date subr-x info cus-start cus-load pixel-scroll
help-mode cl-loaddefs cl-lib iso-transl tooltip eldoc paren electric
uniquify ediff-hook vc-hooks lisp-float-type elisp-mode mwheel
term/x-win x-win term/common-win x-dnd tool-bar dnd fontset image
regexp-opt fringe tabulated-list replace newcomment text-mode lisp-mode
prog-mode register page tab-bar menu-bar rfn-eshadow isearch easymenu
timer select scroll-bar mouse jit-lock font-lock syntax font-core
term/tty-colors frame minibuffer cl-generic cham georgian utf-8-lang
misc-lang vietnamese tibetan thai tai-viet lao korean japanese eucjp-ms
cp51932 hebrew greek romanian slovak czech european ethiopic indian
cyrillic chinese composite emoji-zwj charscript charprop case-table
epa-hook jka-cmpr-hook help simple abbrev obarray cl-preloaded nadvice
button loaddefs faces cus-face macroexp files window text-properties
overlay sha1 md5 base64 format env code-pages mule custom widget
hashtable-print-readable backquote threads xwidget-internal dbusbind
inotify lcms2 dynamic-setting system-font-setting font-render-setting
cairo move-toolbar gtk x-toolkit x multi-tty make-network-process emacs)

Memory information:
((conses 16 136507 9602)
 (symbols 48 8087 1)
 (strings 32 29616 2128)
 (string-bytes 1 988001)
 (vectors 16 14616)
 (vector-slots 8 197714 10580)
 (floats 8 32 44)
 (intervals 56 20288 5)
 (buffers 992 13))

bug#51886: 29.0.50; pixel-scroll-mode garbage collects like crazy

[Eli Zaretskii]

> Date: Tue, 16 Nov 2021 15:21:31 +0800
> From:  Po Lu via "Bug reports for GNU Emacs,
>  the Swiss army knife of text editors" <bug-gnu-emacs@gnu.org>
> 
> Starting from `emacs -Q', do M-x pixel-scroll-mode RET, then configure
> it as follows:
> 
>     (setq pixel-dead-time 0)
>     (setq pixel-resolution-fine-flag 1)
>     (setq garbage-collection-messages t)
> 
> Then scroll the display with the mouse wheel.  It will garbage collect
> like crazy, leading to a great deal of stuttering (in emacs-28 as well).
> 
> I want to reuse most of the code in pixel-scroll.el for XInput2 pixel
> scrolling, but this is holding me back, as the excessive garbage
> collection makes it completely unusable.

Did you try to figure out which part of the code produces most of the
garbage?

bug#51886: 29.0.50; pixel-scroll-mode garbage collects like crazy

[Po Lu via Bug reports for GNU Emacs, the Swiss army knife of text editors]

[-- Attachment #1: Type: text/plain, Size: 4143 bytes --]

Eli Zaretskii <eliz@gnu.org> writes:

>> Date: Tue, 16 Nov 2021 15:21:31 +0800
>> From:  Po Lu via "Bug reports for GNU Emacs,
>>  the Swiss army knife of text editors" <bug-gnu-emacs@gnu.org>
>> 
>> Starting from `emacs -Q', do M-x pixel-scroll-mode RET, then configure
>> it as follows:
>> 
>>     (setq pixel-dead-time 0)
>>     (setq pixel-resolution-fine-flag 1)
>>     (setq garbage-collection-messages t)
>> 
>> Then scroll the display with the mouse wheel.  It will garbage collect
>> like crazy, leading to a great deal of stuttering (in emacs-28 as well).
>> 
>> I want to reuse most of the code in pixel-scroll.el for XInput2 pixel
>> scrolling, but this is holding me back, as the excessive garbage
>> collection makes it completely unusable.
>
> Did you try to figure out which part of the code produces most of the
> garbage?

Here's the report from the memory profiler scrolling down (emacs)Top
with those settings applied in Info:

    347,738,992  30% + beginning-of-visual-line
    203,047,297  17% + end-of-visual-line
    170,995,572  14% + pixel-posn-y-at-point
    143,277,076  12% + pixel-visual-line-height
    113,156,817   9% + pixel-visible-pos-in-window
     99,928,040   8% + if
     11,567,121   1% + pixel-line-height
      9,885,201   0% + pixel--whistlestop-pixel-up
      9,471,180   0% + pixel--whistlestop-line-up
      7,420,310   0% + redisplay
      5,325,728   0% + window-current-scroll-bars
      4,814,936   0% + pixel-scroll-up
      4,092,960   0% + pixel-eob-at-top-p
      3,597,328   0% + profiler-stop
      2,783,202   0% + unless
      2,146,848   0% + window-edges
      1,586,384   0% + sit-for
      1,448,085   0% + window-inside-pixel-edges
      1,297,072   0% + pixel-point-at-top-p
      1,196,572   0% + pixel-scroll-pixel-up
        978,872   0% + mouse-wheel--get-scroll-window
        268,778   0% + apply
        220,291   0% + eval
        166,360   0% + c-type-finder-timer-func
        155,896   0% + timer--time-less-p
        144,822   0% + read-from-minibuffer
        117,312   0% + execute-extended-command
        105,840   0% + timer--time-setter
        102,392   0% + timer-relative-time
         95,312   0% + timer-create
         94,648   0% + pixel-scroll-in-rush-p
         83,304   0% + Info-check-pointer
         66,944   0% + mwheel-scroll
         65,968   0% + Info-extract-pointer
         38,435   0% + completing-read-default
         38,008   0% + frame-focus-state
         32,736   0% + funcall-interactively
         29,768   0% + posn-at-point
         22,176   0% + timer-activate
         17,952   0% + window-pixel-edges
         17,136   0% + call-interactively
         15,840   0% + redisplay_internal (C function)
         12,664   0% + command-execute
         12,432   0% + jit-lock--run-functions
         11,248   0% + menu-bar-update-buffers-1
          8,288   0% + #<compiled 0x19a292a7afa00b7d>
          8,184   0% + x-gtk-map-stock
          7,494   0% + window-frame
          7,432   0% + pos-visible-in-window-p
          7,312   0% + jit-lock-fontify-now
          6,336   0% + #<compiled 0xa2ad9af8e9ade27>
          6,336   0% + user-error
          6,336   0% + undo-auto--boundaries
          3,810   0% + line-number-at-pos
          2,120   0% + scroll-up
          1,959   0%   timer-event-handler
          1,921   0% + fboundp
          1,905   0% + window-scroll-bars
          1,905   0% + constrain-to-field
          1,905   0%   clear-minibuffer-message
          1,905   0% + frame-live-p
          1,863   0% + window-margins
          1,863   0% + line-pixel-height
          1,863   0% + mwheel-event-button
          1,863   0% + profiler-memory-running-p
          1,056   0% + handle-focus-in
          1,056   0% + minibuffer-mode
          1,056   0% + #<compiled 0x1d710e244bc5248e>
          1,056   0% + menu-bar-update-buffers
          1,056   0% + keymap-canonicalize
          1,056   0% + run-hooks
          1,024   0%   mouse-fixup-help-message
            912   0% + count-lines
            631   0% + profiler-start
             21   0% + generate-new-buffer

And here's the entire profile:


[-- Attachment #2: profile --]
[-- Type: application/octet-stream, Size: 34945 bytes --]


[profiler-profile "28.1" memory #s(hash-table size 217 test equal rehash-size 1.5 rehash-threshold 0.8125 data ([fboundp profiler-stop funcall-interactively call-interactively command-execute execute-extended-command funcall-interactively call-interactively command-execute nil nil nil nil nil nil nil] 1921 [profiler-start funcall-interactively call-interactively command-execute execute-extended-command funcall-interactively call-interactively command-execute nil nil nil nil nil nil nil nil] 631 [timer-relative-time run-at-time execute-extended-command funcall-interactively call-interactively command-execute nil nil nil nil nil nil nil nil nil nil] 8 [timer--time-setter timer-set-time run-at-time execute-extended-command funcall-interactively call-interactively command-execute nil nil nil nil nil nil nil nil nil] 24 [timer--time-less-p timer--activate timer-activate run-at-time execute-extended-command funcall-interactively call-interactively command-execute nil nil nil nil nil nil nil nil] 72 [nil nil nil nil nil nil nil nil nil nil nil nil nil nil nil nil] 13066475 [timer-relative-time run-at-time c-type-finder-timer-func apply timer-event-handler nil nil nil nil nil nil nil nil nil nil nil] 37752 [timer--time-setter timer-set-time run-at-time c-type-finder-timer-func apply timer-event-handler nil nil nil nil nil nil nil nil nil nil] 40272 [timer--time-less-p timer--activate timer-activate run-at-time c-type-finder-timer-func apply timer-event-handler nil nil nil nil nil nil nil nil nil] 3312 [menu-bar-update-buffers-1 menu-bar-update-buffers redisplay_internal\ \(C\ function\) nil nil nil nil nil nil nil nil nil nil nil nil nil] 1008 [apply user-error Info-extract-pointer Info-check-pointer redisplay_internal\ \(C\ function\) nil nil nil nil nil nil nil nil nil nil nil] 2646 [x-gtk-map-stock redisplay_internal\ \(C\ function\) nil nil nil nil nil nil nil nil nil nil nil nil nil nil] 8184 [c-type-finder-timer-func apply timer-event-handler nil nil nil nil nil nil nil nil nil nil nil nil nil] 101752 [timer-relative-time run-at-time apply run-with-timer blink-cursor--start-timer blink-cursor-start apply timer-event-handler nil nil nil nil nil nil nil nil] 240 [timer--time-setter timer-set-time run-at-time apply run-with-timer blink-cursor--start-timer blink-cursor-start apply timer-event-handler nil nil nil nil nil nil nil] 120 [timer--time-less-p timer--activate timer-activate run-at-time apply run-with-timer blink-cursor--start-timer blink-cursor-start apply timer-event-handler nil nil nil nil nil nil] 4312 [pixel-scroll-in-rush-p pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil nil nil nil nil nil nil] 94512 [beginning-of-visual-line pixel-posn-y-at-point pixel-point-at-top-p pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil nil nil nil nil] 169204520 [pixel-posn-y-at-point pixel-point-at-top-p pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil nil nil nil nil nil] 170986292 [beginning-of-visual-line pixel-visible-pos-in-window pixel-visual-line-height pixel-line-height pixel-scroll-pixel-up pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil nil nil] 169120144 [end-of-visual-line pixel-visible-pos-in-window pixel-visual-line-height pixel-line-height pixel-scroll-pixel-up pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil nil nil] 192374473 [pixel-visible-pos-in-window pixel-visual-line-height pixel-line-height pixel-scroll-pixel-up pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil nil nil nil] 107381829 [pixel-visual-line-height pixel-line-height pixel-scroll-pixel-up pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil nil nil nil nil] 135743128 [pixel--whistlestop-pixel-up pixel-scroll-pixel-up pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil nil nil nil nil nil] 9885201 [sit-for pixel--whistlestop-pixel-up pixel-scroll-pixel-up pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil nil nil nil nil] 1484096 [redisplay sit-for pixel--whistlestop-pixel-up pixel-scroll-pixel-up pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil nil nil nil] 6995680 [apply user-error Info-extract-pointer Info-check-pointer redisplay_internal\ \(C\ function\) redisplay sit-for pixel--whistlestop-pixel-up pixel-scroll-pixel-up pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute nil nil] 238992 [timer-relative-time run-at-time apply run-with-timer mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil nil nil nil nil] 41264 [timer--time-setter timer-set-time run-at-time apply run-with-timer mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil nil nil nil] 39024 [timer--time-less-p timer--activate timer-activate run-at-time apply run-with-timer mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil nil nil] 82880 [pixel-line-height pixel-scroll-pixel-up pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil nil nil nil nil nil] 10886218 [timer-relative-time run-at-time c-type-finder-timer-func apply timer-event-handler input-pending-p sit-for pixel--whistlestop-pixel-up pixel-scroll-pixel-up pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute nil nil] 20248 [timer--time-setter timer-set-time run-at-time c-type-finder-timer-func apply timer-event-handler input-pending-p sit-for pixel--whistlestop-pixel-up pixel-scroll-pixel-up pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute nil] 19488 [timer--time-less-p timer--activate timer-activate run-at-time c-type-finder-timer-func apply timer-event-handler input-pending-p sit-for pixel--whistlestop-pixel-up pixel-scroll-pixel-up pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute] 47832 [pixel-eob-at-top-p pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil nil nil nil nil nil nil] 4092960 [if eval pos-visible-in-window-p pixel-visible-pos-in-window pixel-visual-line-height pixel-line-height pixel-scroll-pixel-up pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil] 47141624 [beginning-of-visual-line pixel-visible-pos-in-window pixel-visual-line-height pixel-line-height pixel--whistlestop-line-up pixel-scroll-pixel-up pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil nil] 9394168 [end-of-visual-line pixel-visible-pos-in-window pixel-visual-line-height pixel-line-height pixel--whistlestop-line-up pixel-scroll-pixel-up pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil nil] 10661304 [pixel-visible-pos-in-window pixel-visual-line-height pixel-line-height pixel--whistlestop-line-up pixel-scroll-pixel-up pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil nil nil] 5765980 [pixel-visual-line-height pixel-line-height pixel--whistlestop-line-up pixel-scroll-pixel-up pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil nil nil nil] 7525788 [pixel-line-height pixel--whistlestop-line-up pixel-scroll-pixel-up pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil nil nil nil nil] 680903 [pixel--whistlestop-line-up pixel-scroll-pixel-up pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil nil nil nil nil nil] 9471180 [sit-for pixel--whistlestop-line-up pixel-scroll-pixel-up pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil nil nil nil nil] 102192 [pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil nil nil nil nil nil nil nil] 4814936 [pixel-point-at-top-p pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil nil nil nil nil nil nil] 1297072 [if eval posn-at-point pixel-posn-y-at-point pixel-point-at-top-p pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil nil nil] 47176168 [window-current-scroll-bars window-edges window-inside-pixel-edges pixel-visible-pos-in-window pixel-visual-line-height pixel-line-height pixel-scroll-pixel-up pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil] 5039552 [window-edges window-inside-pixel-edges pixel-visible-pos-in-window pixel-visual-line-height pixel-line-height pixel-scroll-pixel-up pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil nil] 2041248 [if eval pos-visible-in-window-p pixel-visible-pos-in-window pixel-visual-line-height pixel-line-height pixel--whistlestop-line-up pixel-scroll-pixel-up pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil] 2643960 [if eval scroll-up pixel--whistlestop-line-up pixel-scroll-pixel-up pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil nil nil] 2619136 [unless eval scroll-up pixel--whistlestop-line-up pixel-scroll-pixel-up pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil nil nil] 73920 [unless eval posn-at-point pixel-posn-y-at-point pixel-point-at-top-p pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil nil nil] 1337745 [mouse-wheel--get-scroll-window mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil nil nil nil nil nil nil nil] 978872 [window-inside-pixel-edges pixel-visible-pos-in-window pixel-visual-line-height pixel-line-height pixel-scroll-pixel-up pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil nil nil] 1366773 [unless eval pos-visible-in-window-p pixel-visible-pos-in-window pixel-visual-line-height pixel-line-height pixel-scroll-pixel-up pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil] 1274385 [window-current-scroll-bars window-edges window-inside-pixel-edges pixel-visible-pos-in-window pixel-visual-line-height pixel-line-height pixel--whistlestop-line-up pixel-scroll-pixel-up pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil] 285120 [unless eval pos-visible-in-window-p pixel-visible-pos-in-window pixel-visual-line-height pixel-line-height pixel--whistlestop-line-up pixel-scroll-pixel-up pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil] 81312 [window-edges window-inside-pixel-edges pixel-visible-pos-in-window pixel-visual-line-height pixel-line-height pixel--whistlestop-line-up pixel-scroll-pixel-up pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil] 105600 [pixel-scroll-pixel-up pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil nil nil nil nil nil nil] 1196572 [call-interactively command-execute nil nil nil nil nil nil nil nil nil nil nil nil nil nil] 16896 [window-inside-pixel-edges pixel-visible-pos-in-window pixel-visual-line-height pixel-line-height pixel--whistlestop-line-up pixel-scroll-pixel-up pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil nil] 80256 ["#<compiled 0x19a292a7afa00b7d>" run-hook-wrapped jit-lock--run-functions jit-lock-fontify-now jit-lock-function nil nil nil nil nil nil nil nil nil nil nil] 8288 [timer-activate run-at-time c-type-finder-timer-func apply timer-event-handler input-pending-p sit-for pixel--whistlestop-pixel-up pixel-scroll-pixel-up pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute nil nil] 6336 [c-type-finder-timer-func apply timer-event-handler input-pending-p sit-for pixel--whistlestop-pixel-up pixel-scroll-pixel-up pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil] 60080 [eval posn-at-point pixel-posn-y-at-point pixel-point-at-top-p pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil nil nil nil] 101926 [jit-lock-fontify-now jit-lock-function nil nil nil nil nil nil nil nil nil nil nil nil nil nil] 7312 [funcall-interactively call-interactively command-execute nil nil nil nil nil nil nil nil nil nil nil nil nil] 32736 [eval pos-visible-in-window-p pixel-visible-pos-in-window pixel-visual-line-height pixel-line-height pixel-scroll-pixel-up pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil nil] 101346 [timer-create run-at-time c-type-finder-timer-func apply timer-event-handler input-pending-p sit-for pixel--whistlestop-line-up pixel-scroll-pixel-up pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute nil nil] 4144 [timer-relative-time run-at-time c-type-finder-timer-func apply timer-event-handler input-pending-p sit-for pixel--whistlestop-line-up pixel-scroll-pixel-up pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute nil nil] 1176 [timer--time-setter timer-set-time run-at-time c-type-finder-timer-func apply timer-event-handler input-pending-p sit-for pixel--whistlestop-line-up pixel-scroll-pixel-up pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute nil] 4320 [timer--time-less-p timer--activate timer-activate run-at-time c-type-finder-timer-func apply timer-event-handler input-pending-p sit-for pixel--whistlestop-line-up pixel-scroll-pixel-up pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute] 3264 [window-scroll-bars window-current-scroll-bars window-edges window-inside-pixel-edges pixel-visible-pos-in-window pixel-visual-line-height pixel-line-height pixel-scroll-pixel-up pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil] 1905 [command-execute nil nil nil nil nil nil nil nil nil nil nil nil nil nil nil] 9504 [eval scroll-up pixel--whistlestop-line-up pixel-scroll-pixel-up pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil nil nil nil] 9399 [scroll-up pixel--whistlestop-line-up pixel-scroll-pixel-up pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil nil nil nil nil] 2120 [posn-at-point pixel-posn-y-at-point pixel-point-at-top-p pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil nil nil nil nil] 29768 [timer-create run-at-time c-type-finder-timer-func apply timer-event-handler input-pending-p sit-for pixel--whistlestop-pixel-up pixel-scroll-pixel-up pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute nil nil] 8288 [constrain-to-field beginning-of-visual-line pixel-visible-pos-in-window pixel-visual-line-height pixel-line-height pixel-scroll-pixel-up pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil nil] 1905 [c-type-finder-timer-func apply timer-event-handler input-pending-p sit-for pixel--whistlestop-line-up pixel-scroll-pixel-up pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil] 3248 [pos-visible-in-window-p pixel-visible-pos-in-window pixel-visual-line-height pixel-line-height pixel-scroll-pixel-up pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil nil nil] 7096 [mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil nil nil nil nil nil nil nil nil] 66944 ["#<compiled 0xa2ad9af8e9ade27>" mapcar tool-bar-make-keymap-1 tool-bar-make-keymap redisplay_internal\ \(C\ function\) redisplay sit-for pixel--whistlestop-pixel-up pixel-scroll-pixel-up pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute nil nil] 4224 [if eval redisplay_internal\ \(C\ function\) redisplay sit-for pixel--whistlestop-pixel-up pixel-scroll-pixel-up pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil] 310192 [redisplay sit-for pixel--whistlestop-line-up pixel-scroll-pixel-up pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil nil nil nil] 399158 [apply user-error Info-extract-pointer Info-check-pointer redisplay_internal\ \(C\ function\) redisplay sit-for pixel--whistlestop-line-up pixel-scroll-pixel-up pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute nil nil] 13396 [if eval redisplay_internal\ \(C\ function\) redisplay sit-for pixel--whistlestop-line-up pixel-scroll-pixel-up pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil] 19008 [Info-check-pointer redisplay_internal\ \(C\ function\) redisplay sit-for pixel--whistlestop-pixel-up pixel-scroll-pixel-up pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil nil] 83304 [Info-extract-pointer Info-check-pointer redisplay_internal\ \(C\ function\) redisplay sit-for pixel--whistlestop-pixel-up pixel-scroll-pixel-up pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil] 57784 [apply "#<compiled 0xd68d6cb8cde21e3>" redisplay_internal\ \(C\ function\) redisplay sit-for pixel--whistlestop-pixel-up pixel-scroll-pixel-up pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil] 3168 [window-pixel-edges window-at-side-p mode-line-default-help-echo redisplay_internal\ \(C\ function\) redisplay sit-for pixel--whistlestop-pixel-up pixel-scroll-pixel-up pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil] 15840 [unless eval redisplay_internal\ \(C\ function\) redisplay sit-for pixel--whistlestop-pixel-up pixel-scroll-pixel-up pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil] 15840 [user-error Info-extract-pointer Info-check-pointer redisplay_internal\ \(C\ function\) redisplay sit-for pixel--whistlestop-pixel-up pixel-scroll-pixel-up pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil] 4224 [redisplay_internal\ \(C\ function\) redisplay sit-for pixel--whistlestop-line-up pixel-scroll-pixel-up pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil nil nil] 2112 [window-pixel-edges window-at-side-p mode-line-default-help-echo redisplay_internal\ \(C\ function\) redisplay sit-for pixel--whistlestop-line-up pixel-scroll-pixel-up pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil] 1056 [timer--time-less-p timer--activate timer-activate-when-idle timer-event-handler nil nil nil nil nil nil nil nil nil nil nil nil] 4224 [undo-auto--boundaries undo-auto--add-boundary nil nil nil nil nil nil nil nil nil nil nil nil nil nil] 5280 [clear-minibuffer-message nil nil nil nil nil nil nil nil nil nil nil nil nil nil nil] 1905 [timer-create run-at-time apply run-with-timer mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil nil nil nil nil] 29008 [jit-lock--run-functions jit-lock-fontify-now jit-lock-function nil nil nil nil nil nil nil nil nil nil nil nil nil] 12432 [eval pos-visible-in-window-p pixel-visible-pos-in-window pixel-visual-line-height pixel-line-height pixel--whistlestop-line-up pixel-scroll-pixel-up pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil] 7620 [timer-activate run-at-time apply run-with-timer mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil nil nil nil nil] 5280 [line-number-at-pos count-lines pixel-eob-at-top-p pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil nil nil nil nil] 3810 [count-lines pixel-eob-at-top-p pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil nil nil nil nil nil] 912 [window-frame window-current-scroll-bars window-edges window-inside-pixel-edges pixel-visible-pos-in-window pixel-visual-line-height pixel-line-height pixel-scroll-pixel-up pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil] 7494 [pos-visible-in-window-p pixel-visible-pos-in-window pixel-visual-line-height pixel-line-height pixel--whistlestop-line-up pixel-scroll-pixel-up pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil nil] 336 [frame-live-p mouse-wheel--get-scroll-window mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil nil nil nil nil nil nil] 1905 [frame-focus-state blink-cursor--should-blink blink-cursor-check blink-cursor--rescan-frames apply "#<compiled 0x19e0d582460a6678>" handle-focus-out funcall-interactively call-interactively command-execute nil nil nil nil nil nil] 17952 [frame-focus-state blink-cursor--should-blink blink-cursor-check blink-cursor--rescan-frames apply "#<compiled 0x19e0d582460a6678>" handle-focus-in funcall-interactively call-interactively command-execute nil nil nil nil nil nil] 20056 [pixel-scroll-in-rush-p pixel-scroll-down mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil nil nil nil nil nil nil] 136 [window-current-scroll-bars window-edges window-inside-pixel-edges pixel-point-at-bottom-p pixel-scroll-down mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil nil nil nil] 1056 [beginning-of-visual-line pixel-posn-y-at-point pixel-point-at-bottom-p pixel-scroll-down mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil nil nil nil nil] 10080 [pixel-posn-y-at-point pixel-point-at-bottom-p pixel-scroll-down mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil nil nil nil nil nil] 9280 [if eval posn-at-point pixel-posn-y-at-point pixel-point-at-bottom-p pixel-scroll-down mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil nil nil] 2112 [beginning-of-visual-line pixel-visible-pos-in-window pixel-visual-line-height pixel-point-at-bottom-p pixel-scroll-down mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil nil nil nil] 10080 [end-of-visual-line pixel-visible-pos-in-window pixel-visual-line-height pixel-point-at-bottom-p pixel-scroll-down mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil nil nil nil] 11520 [window-inside-pixel-edges pixel-visible-pos-in-window pixel-visual-line-height pixel-point-at-bottom-p pixel-scroll-down mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil nil nil nil] 1056 [pixel-visible-pos-in-window pixel-visual-line-height pixel-point-at-bottom-p pixel-scroll-down mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil nil nil nil nil] 9008 [if eval pos-visible-in-window-p pixel-visible-pos-in-window pixel-visual-line-height pixel-point-at-bottom-p pixel-scroll-down mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil nil] 2112 [pixel-visual-line-height pixel-point-at-bottom-p pixel-scroll-down mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil nil nil nil nil nil] 8160 [sit-for pixel-scroll-pixel-down pixel-scroll-down mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil nil nil nil nil nil] 96 [redisplay_internal\ \(C\ function\) nil nil nil nil nil nil nil nil nil nil nil nil nil nil nil] 9504 [timer-create run-at-time c-type-finder-timer-func apply timer-event-handler nil nil nil nil nil nil nil nil nil nil nil] 49728 [timer-activate run-at-time c-type-finder-timer-func apply timer-event-handler nil nil nil nil nil nil nil nil nil nil nil] 8448 [apply "#<compiled 0xd68d6cb8cde21e3>" redisplay_internal\ \(C\ function\) nil nil nil nil nil nil nil nil nil nil nil nil nil] 8448 [apply timer-event-handler nil nil nil nil nil nil nil nil nil nil nil nil nil nil] 2128 [mouse-fixup-help-message nil nil nil nil nil nil nil nil nil nil nil nil nil nil nil] 1024 [generate-new-buffer substitute-command-keys nil nil nil nil nil nil nil nil nil nil nil nil nil nil] 21 [timer-relative-time run-at-time apply run-with-timer add-timeout tooltip-start-delayed-tip tooltip-show-help nil nil nil nil nil nil nil nil nil] 48 [timer--time-setter timer-set-time run-at-time apply run-with-timer add-timeout tooltip-start-delayed-tip tooltip-show-help nil nil nil nil nil nil nil nil] 24 [timer--time-less-p timer--activate timer-activate run-at-time apply run-with-timer add-timeout tooltip-start-delayed-tip tooltip-show-help nil nil nil nil nil nil nil] 72 [timer-event-handler nil nil nil nil nil nil nil nil nil nil nil nil nil nil nil] 1959 [timer-relative-time timer-inc-time timer-event-handler nil nil nil nil nil nil nil nil nil nil nil nil nil] 256 [timer--time-setter timer-inc-time timer-event-handler nil nil nil nil nil nil nil nil nil nil nil nil nil] 96 [timer--time-less-p timer--activate timer-activate timer-event-handler nil nil nil nil nil nil nil nil nil nil nil nil] 2256 [redisplay sit-for pixel-scroll-pixel-down pixel-scroll-down mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil nil nil nil nil] 25472 [if eval scroll-up pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil nil nil nil nil] 11616 [window-margins window-edges window-inside-pixel-edges pixel-visible-pos-in-window pixel-visual-line-height pixel-line-height pixel-scroll-pixel-up pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil] 1863 [line-pixel-height pixel-visual-line-height pixel-line-height pixel-scroll-pixel-up pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil nil nil nil] 1863 [mwheel-event-button mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil nil nil nil nil nil nil nil] 1863 [timer-activate run-at-time c-type-finder-timer-func apply timer-event-handler input-pending-p sit-for pixel--whistlestop-line-up pixel-scroll-pixel-up pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute nil nil] 1056 [redisplay_internal\ \(C\ function\) redisplay sit-for pixel--whistlestop-pixel-up pixel-scroll-pixel-up pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil nil nil] 4224 [user-error Info-extract-pointer Info-check-pointer redisplay_internal\ \(C\ function\) redisplay sit-for pixel--whistlestop-line-up pixel-scroll-pixel-up pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil] 2112 [Info-extract-pointer Info-check-pointer redisplay_internal\ \(C\ function\) redisplay sit-for pixel--whistlestop-line-up pixel-scroll-pixel-up pixel-scroll-up mwheel-scroll funcall-interactively call-interactively command-execute nil nil nil nil] 8184 [timer--time-setter timer-set-idle-time run-with-idle-timer blink-cursor--start-idle-timer blink-cursor-check blink-cursor--rescan-frames apply "#<compiled 0x19e0d582460a6678>" handle-focus-in funcall-interactively call-interactively command-execute nil nil nil nil] 1056 [handle-focus-in funcall-interactively call-interactively command-execute nil nil nil nil nil nil nil nil nil nil nil nil] 1056 [timer--time-less-p timer--activate timer-activate-when-idle run-with-idle-timer blink-cursor--start-idle-timer blink-cursor-check blink-cursor--rescan-frames apply "#<compiled 0x19e0d582460a6678>" handle-focus-in funcall-interactively call-interactively command-execute nil nil nil] 1056 [completing-read-default completing-read read-extended-command byte-code call-interactively command-execute nil nil nil nil nil nil nil nil nil nil] 38435 [minibuffer-mode read-from-minibuffer completing-read-default completing-read read-extended-command byte-code call-interactively command-execute nil nil nil nil nil nil nil nil] 1056 [timer-relative-time run-at-time undo-auto--boundary-ensure-timer undo-auto--undoable-change read-from-minibuffer completing-read-default completing-read read-extended-command byte-code call-interactively command-execute nil nil nil nil nil] 1064 [timer--time-setter timer-set-time run-at-time undo-auto--boundary-ensure-timer undo-auto--undoable-change read-from-minibuffer completing-read-default completing-read read-extended-command byte-code call-interactively command-execute nil nil nil nil] 24 [timer--time-less-p timer--activate timer-activate run-at-time undo-auto--boundary-ensure-timer undo-auto--undoable-change read-from-minibuffer completing-read-default completing-read read-extended-command byte-code call-interactively command-execute nil nil nil] 24 ["#<compiled 0x1d710e244bc5248e>" minibuffer-setup read-from-minibuffer completing-read-default completing-read read-extended-command byte-code call-interactively command-execute nil nil nil nil nil nil nil] 1056 [menu-bar-update-buffers-1 menu-bar-update-buffers redisplay_internal\ \(C\ function\) read-from-minibuffer completing-read-default completing-read read-extended-command byte-code call-interactively command-execute nil nil nil nil nil nil] 10240 [menu-bar-update-buffers redisplay_internal\ \(C\ function\) read-from-minibuffer completing-read-default completing-read read-extended-command byte-code call-interactively command-execute nil nil nil nil nil nil nil] 1056 [keymap-canonicalize redisplay_internal\ \(C\ function\) read-from-minibuffer completing-read-default completing-read read-extended-command byte-code call-interactively command-execute nil nil nil nil nil nil nil] 1056 [read-from-minibuffer completing-read-default completing-read read-extended-command byte-code call-interactively command-execute nil nil nil nil nil nil nil nil nil] 144822 ["#<compiled 0xa2ad9af8e9ade27>" mapcar tool-bar-make-keymap-1 tool-bar-make-keymap redisplay_internal\ \(C\ function\) read-from-minibuffer completing-read-default completing-read read-extended-command byte-code call-interactively command-execute nil nil nil nil] 2112 [window-pixel-edges window-at-side-p mode-line-default-help-echo redisplay_internal\ \(C\ function\) read-from-minibuffer completing-read-default completing-read read-extended-command byte-code call-interactively command-execute nil nil nil nil nil] 1056 [if eval redisplay_internal\ \(C\ function\) read-from-minibuffer completing-read-default completing-read read-extended-command byte-code call-interactively command-execute nil nil nil nil nil nil] 2112 [c-type-finder-timer-func apply timer-event-handler read-from-minibuffer completing-read-default completing-read read-extended-command byte-code call-interactively command-execute nil nil nil nil nil nil] 1280 [timer-create run-at-time c-type-finder-timer-func apply timer-event-handler read-from-minibuffer completing-read-default completing-read read-extended-command byte-code call-interactively command-execute nil nil nil nil] 4144 [timer-relative-time run-at-time c-type-finder-timer-func apply timer-event-handler read-from-minibuffer completing-read-default completing-read read-extended-command byte-code call-interactively command-execute nil nil nil nil] 336 [timer--time-setter timer-set-time run-at-time c-type-finder-timer-func apply timer-event-handler read-from-minibuffer completing-read-default completing-read read-extended-command byte-code call-interactively command-execute nil nil nil] 1392 [timer--time-less-p timer--activate timer-activate run-at-time c-type-finder-timer-func apply timer-event-handler read-from-minibuffer completing-read-default completing-read read-extended-command byte-code call-interactively command-execute nil nil] 5536 [call-interactively command-execute read-from-minibuffer completing-read-default completing-read read-extended-command byte-code call-interactively command-execute nil nil nil nil nil nil nil] 224 [undo-auto--boundaries undo-auto--add-boundary read-from-minibuffer completing-read-default completing-read read-extended-command byte-code call-interactively command-execute nil nil nil nil nil nil nil] 1056 [command-execute read-from-minibuffer completing-read-default completing-read read-extended-command byte-code call-interactively command-execute nil nil nil nil nil nil nil nil] 3160 [timer--time-less-p timer--activate timer-activate-when-idle timer-event-handler read-from-minibuffer completing-read-default completing-read read-extended-command byte-code call-interactively command-execute nil nil nil nil nil] 1056 [timer-activate run-at-time c-type-finder-timer-func apply timer-event-handler read-from-minibuffer completing-read-default completing-read read-extended-command byte-code call-interactively command-execute nil nil nil nil] 1056 [run-hooks run-mode-hooks minibuffer-inactive-mode read-from-minibuffer completing-read-default completing-read read-extended-command byte-code call-interactively command-execute nil nil nil nil nil nil] 1056 [execute-extended-command funcall-interactively call-interactively command-execute nil nil nil nil nil nil nil nil nil nil nil nil] 117312 [call-interactively command-execute execute-extended-command funcall-interactively call-interactively command-execute nil nil nil nil nil nil nil nil nil nil] 16 [profiler-stop funcall-interactively call-interactively command-execute execute-extended-command funcall-interactively call-interactively command-execute nil nil nil nil nil nil nil nil] 3597328 [profiler-memory-running-p profiler-stop funcall-interactively call-interactively command-execute execute-extended-command funcall-interactively call-interactively command-execute nil nil nil nil nil nil nil] 1863)) (24979 44717 219275 913000) nil]

[-- Attachment #3: Type: text/plain, Size: 28 bytes --]


I hope this helps, thanks.

bug#51886: 29.0.50; pixel-scroll-mode garbage collects like crazy

[Robert Pluim]

>>>>> On Tue, 16 Nov 2021 15:05:32 +0200, Eli Zaretskii <eliz@gnu.org> said:

    >> Date: Tue, 16 Nov 2021 15:21:31 +0800
    >> From:  Po Lu via "Bug reports for GNU Emacs,
    >> the Swiss army knife of text editors" <bug-gnu-emacs@gnu.org>
    >> 
    >> Starting from `emacs -Q', do M-x pixel-scroll-mode RET, then configure
    >> it as follows:
    >> 
    >> (setq pixel-dead-time 0)
    >> (setq pixel-resolution-fine-flag 1)
    >> (setq garbage-collection-messages t)
    >> 
    >> Then scroll the display with the mouse wheel.  It will garbage collect
    >> like crazy, leading to a great deal of stuttering (in emacs-28 as well).
    >> 
    >> I want to reuse most of the code in pixel-scroll.el for XInput2 pixel
    >> scrolling, but this is holding me back, as the excessive garbage
    >> collection makes it completely unusable.

    Eli> Did you try to figure out which part of the code produces most of the
    Eli> garbage?

I suspect itʼs the bit that counts from k to n by generating a list of
the integers from k to n and then running dolist over that.

As an aside, that code also does a lot of (sit-for 0), which I seem to
remember can trigger redisplay? Perhaps it should only do that when it
really wants to pause.

Robert
-- 

bug#51886: 29.0.50; pixel-scroll-mode garbage collects like crazy

[Eli Zaretskii]

> From: Po Lu <luangruo@yahoo.com>
> Cc: 51886@debbugs.gnu.org
> Date: Tue, 16 Nov 2021 21:17:55 +0800
> 
> > Did you try to figure out which part of the code produces most of the
> > garbage?
> 
> Here's the report from the memory profiler scrolling down (emacs)Top
> with those settings applied in Info:

The so-called "memory profiler" doesn't actually collect memory usage
statistics, so it's useless for this job.

I don't think we have tools ready for the job.  I suggest to
instrument the code involved in this and see what kind of objects get
consed the most, and by which code.

bug#51886: 29.0.50; pixel-scroll-mode garbage collects like crazy

[Eli Zaretskii]

> From: Robert Pluim <rpluim@gmail.com>
> Cc: Po Lu <luangruo@yahoo.com>,  51886@debbugs.gnu.org
> Date: Tue, 16 Nov 2021 14:28:23 +0100
> 
> I suspect itʼs the bit that counts from k to n by generating a list of
> the integers from k to n and then running dolist over that.

Maybe, but I think we want a more direct evidence.

> As an aside, that code also does a lot of (sit-for 0), which I seem to
> remember can trigger redisplay? Perhaps it should only do that when it
> really wants to pause.

It doesn't want to pause, it wants to trigger redisplay.  Without that
the stuff will not work.

bug#51886: 29.0.50; pixel-scroll-mode garbage collects like crazy

[Po Lu via Bug reports for GNU Emacs, the Swiss army knife of text editors]

Eli Zaretskii <eliz@gnu.org> writes:

>> I suspect itʼs the bit that counts from k to n by generating a list of
>> the integers from k to n and then running dolist over that.
>
> Maybe, but I think we want a more direct evidence.

Sadly, it's not the case here.  Rewriting `pixel--whistlestop-pixel-up'
to not cons (such as with number-sequence) yields no visible
improvement.

bug#51886: 29.0.50; pixel-scroll-mode garbage collects like crazy, Re: bug#51886: 29.0.50; pixel-scroll-mode garbage collects like crazy

[Robert Pluim]

>>>>> On Tue, 16 Nov 2021 15:38:36 +0200, Eli Zaretskii <eliz@gnu.org> said:

    Eli> It doesn't want to pause, it wants to trigger redisplay.  Without that
    Eli> the stuff will not work.

Replacing them all with
          (when (not (zerop pixel-wait))
             (sit-for pixel-wait)

doesnʼt seem to have broken anything....

>>>>> On Tue, 16 Nov 2021 21:41:29 +0800, Po Lu <luangruo@yahoo.com> said:

    Po> Eli Zaretskii <eliz@gnu.org> writes:

    >>> I suspect itʼs the bit that counts from k to n by generating a list of
    >>> the integers from k to n and then running dolist over that.
    >> 
    >> Maybe, but I think we want a more direct evidence.

    Po> Sadly, it's not the case here.  Rewriting `pixel--whistlestop-pixel-up'
    Po> to not cons (such as with number-sequence) yields no visible
    Po> improvement.

Hmm. Changing the catch/throw in `pixel-scroll-up' to

          (while (and (pixel-point-at-top-p amt)
                      (>= (vertical-motion 1) 1)))

seems to help. As does removing mode-line-remote from mode-line-format
(the profiler said we were calling `file-remote-p' a lot).

Robert
-- 

bug#51886: 29.0.50; pixel-scroll-mode garbage collects like crazy

[Lars Ingebrigtsen]

Po Lu <luangruo@yahoo.com> writes:

> Starting from `emacs -Q', do M-x pixel-scroll-mode RET, then configure
> it as follows:
>
>     (setq pixel-dead-time 0)
>     (setq pixel-resolution-fine-flag 1)
>     (setq garbage-collection-messages t)
>
> Then scroll the display with the mouse wheel.  It will garbage collect
> like crazy, leading to a great deal of stuttering (in emacs-28 as well).
>
> I want to reuse most of the code in pixel-scroll.el for XInput2 pixel
> scrolling, but this is holding me back, as the excessive garbage
> collection makes it completely unusable.

This was almost a year ago, and I think you've fixed a bunch of things
in this area meanwhile, if I remember correctly?  Is this bug report
still relevant?  (I haven't tried to reproduce the problem myself.)

bug#51886: 29.0.50; pixel-scroll-mode garbage collects like crazy

[Po Lu via Bug reports for GNU Emacs, the Swiss army knife of text editors]

Lars Ingebrigtsen <larsi@gnus.org> writes:

> This was almost a year ago, and I think you've fixed a bunch of things
> in this area meanwhile, if I remember correctly?  Is this bug report
> still relevant?  (I haven't tried to reproduce the problem myself.)

pixel-scroll-mode is still buggy and generates an incredible amount of
garbage.  However, pixel-scroll-precision-mode was eventually written to
use its own code, without touching the rest of the code in
pixel-scroll.el, so this bug report is not as relevant as it used to be.

I'm curious as to whether or not there are people still using the old
pixel-scroll-mode, especially since pixel-scroll-precision-mode should
now work "out of the box" with wheel mice on X.

bug#51886: 29.0.50; pixel-scroll-mode garbage collects like crazy

[Stefan Kangas]

Po Lu via "Bug reports for GNU Emacs, the Swiss army knife of text
editors" <bug-gnu-emacs@gnu.org> writes:

> pixel-scroll-mode is still buggy and generates an incredible amount of
> garbage.  However, pixel-scroll-precision-mode was eventually written to
> use its own code, without touching the rest of the code in
> pixel-scroll.el, so this bug report is not as relevant as it used to be.

Is `pixel-scroll-precision-mode' supposed to be a drop-in replacement
for `pixel-scroll-mode'?  If yes, how close is it?

> I'm curious as to whether or not there are people still using the old
> pixel-scroll-mode, especially since pixel-scroll-precision-mode should
> now work "out of the box" with wheel mice on X.

With `pixel-scroll-mode', I can see that when I scroll slowly, scrolling
behaves more like it would in Firefox (i.e., smooth rather than not
choppy).

With `pixel-scroll-precision-mode', I'm not sure I can spot any
difference with or without it enabled, when scrolling with the mouse
wheel.

I just found `pixel-scroll-precision-interpolate-page', which makes it
more attractive for me to use.  Is there a way to make it scroll faster
though?  If not, could we add such an option?

BTW, why isn't there a pixel-scroll defgroup under the scroll group
instead?  I tried `M-x customize-group RET pixel TAB' but couldn't find
anything relevant.

bug#51886: 29.0.50; pixel-scroll-mode garbage collects like crazy

[Po Lu via Bug reports for GNU Emacs, the Swiss army knife of text editors]

Stefan Kangas <stefankangas@gmail.com> writes:

> Is `pixel-scroll-precision-mode' supposed to be a drop-in replacement
> for `pixel-scroll-mode'?  If yes, how close is it?

It should be a complete drop-in replacement, except for people who
really, really, like the old line-based "pixel" scrolling.  And I think
it's already there, sans bugs like what you are experiencing.

> With `pixel-scroll-mode', I can see that when I scroll slowly, scrolling
> behaves more like it would in Firefox (i.e., smooth rather than not
> choppy).
>
> With `pixel-scroll-precision-mode', I'm not sure I can spot any
> difference with or without it enabled, when scrolling with the mouse
> wheel.

Hmm, that sounds like a bug.  Could you please run the following code:

  (progn (read-event) (message "Device: %s" last-event-device))

and show what is printed once you turn your mouse wheel?

> I just found `pixel-scroll-precision-interpolate-page', which makes it
> more attractive for me to use.  Is there a way to make it scroll faster
> though?  If not, could we add such an option?

Try playing with pixel-scroll-precision-interpolation-total-time, and
pixel-scroll-precision-interpolation-between-scroll.  I agree those
options should be easier to use, and I will work on them at some point.

> BTW, why isn't there a pixel-scroll defgroup under the scroll group
> instead?  I tried `M-x customize-group RET pixel TAB' but couldn't find
> anything relevant.

Those options are under the "mouse" group, but I won't object to moving
them into their own group.

Thanks.

bug#51886: 29.0.50; pixel-scroll-mode garbage collects like crazy

[Stefan Kangas]

Po Lu <luangruo@yahoo.com> writes:

> It should be a complete drop-in replacement, except for people who
> really, really, like the old line-based "pixel" scrolling.  And I think
> it's already there, sans bugs like what you are experiencing.

It still isn't clear to me why it doesn't just replace the old mode (if
we need to keep it, why not name it `pixel-scroll-old-mode'?).  Maybe
I'm missing something.

> Hmm, that sounds like a bug.  Could you please run the following code:
>
>   (progn (read-event) (message "Device: %s" last-event-device))
>
> and show what is printed once you turn your mouse wheel?

"Device: A..... G3"

BTW, is it expected that it ignores the first scroll on the mouse wheel,
and prints the above only on the second?  (Tested in both directions.)

> Try playing with pixel-scroll-precision-interpolation-total-time, and
> pixel-scroll-precision-interpolation-between-scroll.  I agree those
> options should be easier to use, and I will work on them at some point.

Thanks, that will be appreciated.

>> BTW, why isn't there a pixel-scroll defgroup under the scroll group
>> instead?  I tried `M-x customize-group RET pixel TAB' but couldn't find
>> anything relevant.
>
> Those options are under the "mouse" group, but I won't object to moving
> them into their own group.

I created a new bug report for that.

bug#51886: 29.0.50; pixel-scroll-mode garbage collects like crazy

[Po Lu via Bug reports for GNU Emacs, the Swiss army knife of text editors]

Stefan Kangas <stefankangas@gmail.com> writes:

> It still isn't clear to me why it doesn't just replace the old mode (if
> we need to keep it, why not name it `pixel-scroll-old-mode'?).  Maybe
> I'm missing something.

I think Eli preferred to keep the old mode.

> "Device: A..... G3"

Did you censor some information with the periods, or is that literally
what was printed?

> BTW, is it expected that it ignores the first scroll on the mouse wheel,
> and prints the above only on the second?  (Tested in both directions.)

Yes, that's a limitation of the X API.  Emacs needs to swallow an
initial event in order to obtain the "initial" value of the scroll
wheel, before it can obtain scroll deltas by comparing it with the
absolute values of subsequent events.

Thanks.

bug#51886: 29.0.50; pixel-scroll-mode garbage collects like crazy

[Stefan Kangas]

Po Lu <luangruo@yahoo.com> writes:

>> "Device: A..... G3"
>
> Did you censor some information with the periods, or is that literally
> what was printed?

(Sorry for the very late reply here.)

No censoring, this is what was literally printed.

bug#51886: 29.0.50; pixel-scroll-mode garbage collects like crazy

[Po Lu via Bug reports for GNU Emacs, the Swiss army knife of text editors]

Stefan Kangas <stefankangas@gmail.com> writes:

> (Sorry for the very late reply here.)
>
> No censoring, this is what was literally printed.

Hmm, in that case there's nothing from which Emacs can identify it as a
mouse.  I suggest configuring pixel-scroll-precision-large-scroll-height
to a suitable value, as we recommend users do in similar situations.

As for the reason this is not set by default, there is no
one-size-fits-all value for the variable that is guaranteed not to
classify events produced by touchpads as mouse events and lead to
Emacs's interpolating them erroneously, which would upset most users,
who enable pixel-scroll-precision-mode for touchpads only.