Subject: bug#23457: closed (Re: bug#23457: 24.5; interactive use of next-line and previous-line (holding down C-n or C-p) lag in a buffer with all spaces and newlines)

From: [email-masked] (GNU bug Tracking System)
Date: Fri, 06 May 2016 09:25:02 +0000

Your bug report

#23457: 24.5; interactive use of next-line and previous-line (holding down C-n or C-p) lag in a buffer with all spaces and newlines

which was filed against the emacs package, has been closed.

The explanation is attached below, along with your original report.
If you require more details, please reply to [email-masked].

-- 
23457: http://debbugs.gnu.org/cgi/bugreport.cgi?bug=23457
GNU Bug Tracking System
Contact [email-masked] with problems

Subject: Re: bug#23457: 24.5; interactive use of next-line and previous-line (holding down C-n or C-p) lag in a buffer with all spaces and newlines
From: Eli Zaretskii <[email-masked]>
To: James McClain <[email-masked]>
Cc: [email-masked], [email-masked]
Date: Fri, 06 May 2016 12:24:10 +0300
List-Id: <debbugs-submit.debbugs.gnu.org>

> From: James McClain <[email-masked]>
> Date: Fri, 6 May 2016 02:19:24 -0700
> Cc: Nicolas Petton <[email-masked]>, [email-masked]
> 
> There is no real-life use case at all where I can see this problem
> happening, I was just curious as to why.
> Thank you for figuring that out,
> Glad to see I'm not crazy!

Thanks, closing.

Subject: 24.5; interactive use of next-line and previous-line (holding down C-n or C-p) lag in a buffer with all spaces and newlines
From: [email-masked]
To: [email-masked]
Date: Thu, 05 May 2016 02:01:54 -0700
List-Id: <debbugs-submit.debbugs.gnu.org>

This is pretty minor, but it surprised me. When a buffer is filled with
spaces going all the way to the last column without overwrapping. If one
tries to navigate by lines using C-n or C-p and holding them down, there
is noticable lag. My window-body-width is 115 and window-body-height is
60.
Recipe:
1. Open emacs         : Emacs -Q
2. Open a blank buffer: C-x b test-2
3. Fill the buffer up with spaces until it would force a linewrap, then
   use C-j to enter a newline. C-u 115 <space>
                               C-j
4. The buffer should appear blank unless you use whitespace mode, now try
   holding down C-n or C-p. Emacs will lag.

I also tested this in a tty emacs session on linux over ssh, and it
seemed the lag was also aparent over there.

The lag lasted at most around 5 seconds.

If the line has all spaces, one period, then a newline. (So if there is
one non-space character it seems) then this lag does not happen.

Frankly just curious,

James

In GNU Emacs 24.5.1 (x86_64-w64-mingw32)
 of 2015-05-16 on KAEL
Windowing system distributor `Microsoft Corp.', version 6.3.9600
Configured using:
 `configure --prefix=/z/emacs --host=x86_64-w64-mingw32
 --target=x86_64-w64-mingw32 --build=x86_64-w64-mingw32 --with-wide-int
 --with-jpeg --with-xpm --with-png --with-tiff --with-rsvg --with-xml2
 --with-gnutls --with-sound=yes --with-file-notification=yes
 --without-dbus --without-imagemagick 'CFLAGS=-O3 -fomit-frame-pointer
 -g0 -pipe' 'LDFLAGS=-static-libgcc -static-libstdc++ -static -s
 -Wl,-s''

Important settings:
  value of $LANG: ENU
  locale-coding-system: cp1252

Major mode: Fundamental

Minor modes in effect:
  erc-list-mode: t
  erc-menu-mode: t
  erc-autojoin-mode: t
  erc-ring-mode: t
  erc-networks-mode: t
  erc-pcomplete-mode: t
  erc-track-mode: t
  erc-track-minor-mode: t
  erc-match-mode: t
  erc-button-mode: t
  erc-fill-mode: t
  erc-stamp-mode: t
  erc-netsplit-mode: t
  erc-irccontrols-mode: t
  erc-noncommands-mode: t
  erc-move-to-prompt-mode: t
  erc-readonly-mode: t
  tooltip-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
  blink-cursor-mode: t
  auto-composition-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t
  line-number-mode: t
  transient-mark-mode: t

Recent messages:
Checking 57 files in c:/ProgramData/chocolatey/lib/emacs64/tools/emacs/share/emacs/24.5/lisp/eshell...
Checking 70 files in c:/ProgramData/chocolatey/lib/emacs64/tools/emacs/share/emacs/24.5/lisp/erc...
Checking 34 files in c:/ProgramData/chocolatey/lib/emacs64/tools/emacs/share/emacs/24.5/lisp/emulation...
Checking 151 files in c:/ProgramData/chocolatey/lib/emacs64/tools/emacs/share/emacs/24.5/lisp/emacs-lisp...
Checking 24 files in c:/ProgramData/chocolatey/lib/emacs64/tools/emacs/share/emacs/24.5/lisp/cedet...
Checking 57 files in c:/ProgramData/chocolatey/lib/emacs64/tools/emacs/share/emacs/24.5/lisp/calendar...
Checking 87 files in c:/ProgramData/chocolatey/lib/emacs64/tools/emacs/share/emacs/24.5/lisp/calc...
Checking 111 files in c:/ProgramData/chocolatey/lib/emacs64/tools/emacs/share/emacs/24.5/lisp/obsolete...
Checking for load-path shadows...done
Mark set [2 times]
Quit

Load-path shadows:
None found.

Features:
(shadow sort mail-extr misearch multi-isearch noutline outline
easy-mmode view emacsbug message rfc822 mml mml-sec mm-decode mm-bodies
mm-encode mail-parse rfc2231 mailabbrev gmm-utils mailheader sendmail
rfc2047 rfc2045 ietf-drums mail-utils eieio-opt speedbar sb-image
ezimage dframe find-func help-mode network-stream starttls tls erc-list
erc-menu easymenu erc-join erc-ring erc-networks erc-pcomplete pcomplete
comint ansi-color ring erc-track erc-match erc-button wid-edit erc-fill
erc-stamp erc-netsplit erc-goodies erc erc-backend erc-compat
format-spec auth-source eieio byte-opt bytecomp byte-compile cl-extra
cl-loaddefs cl-lib cconv eieio-core gnus-util mm-util help-fns
mail-prsvr password-cache thingatpt pp kmacro whitespace time-date
tooltip electric uniquify ediff-hook vc-hooks lisp-float-type mwheel
dos-w32 ls-lisp w32-common-fns disp-table w32-win w32-vars tool-bar dnd
fontset image regexp-opt fringe tabulated-list newcomment lisp-mode
prog-mode register page menu-bar rfn-eshadow timer select scroll-bar
mouse jit-lock font-lock syntax facemenu font-core frame cham georgian
utf-8-lang misc-lang vietnamese tibetan thai tai-viet lao korean
japanese hebrew greek romanian slovak czech european ethiopic indian
cyrillic chinese case-table epa-hook jka-cmpr-hook help simple abbrev
minibuffer nadvice loaddefs button faces cus-face macroexp files
text-properties overlay sha1 md5 base64 format env code-pages mule
custom widget hashtable-print-readable backquote make-network-process
w32notify w32 multi-tty emacs)

Memory information:
((conses 16 133688 22081)
 (symbols 56 23279 0)
 (miscs 48 130 422)
 (strings 32 29961 2899)
 (string-bytes 1 788055)
 (vectors 16 17076)
 (vector-slots 8 461686 8433)
 (floats 8 87 296)
 (intervals 56 1762 121)
 (buffers 960 22))