This bug report will be sent to the Bug-GNU-Emacs mailing list and the GNU bug tracker at debbugs.gnu.org. Please check that the From: line contains a valid email address. After a delay of up to one day, you should receive an acknowledgment at that address. Please write in English if possible, as the Emacs maintainers usually do not have translators for other languages. Please describe exactly what actions triggered the bug, and the precise symptoms of the bug. If you can, give a recipe starting from `emacs -Q': Open large C++ file (17,000 line in this case). Hold down Page Down key. Emacs will scroll two or three times and then pause for 15 seconds or more. Once you have scrolled to the bottom of the file Page Down will work reasonably, however page up remains slow. emacs -Q is marginally faster than my configuration (just marginally). When doing any scrolling the CPU is maxed. (core 2 duo) Emacs GNU Emacs 22.3.1 (i386-mingw-nt6.1.7601) also has slower initial scroll through, it does not however lock up and after the initial scroll through both page up and page down display every single step. (Initial scroll through is only marginally slower than subsequent ones). If Emacs crashed, and you have the Emacs process in the gdb debugger, please include the output from the following gdb commands: `bt full' and `xbacktrace'. For information about debugging Emacs, please read the file c:/working_chad/emacs_new_current/emacs-24.3/etc/DEBUG. In GNU Emacs 24.3.1 (i386-mingw-nt6.1.7601) of 2013-03-17 on MARVIN Windowing system distributor `Microsoft Corp.', version 6.1.7601 Configured using: `configure --with-gcc (4.7) --cflags -ID:/devel/emacs/libs/libXpm-3.5.8/include -ID:/devel/emacs/libs/libXpm-3.5.8/src -ID:/devel/emacs/libs/libpng-dev_1.4.3-1/include -ID:/devel/emacs/libs/zlib-dev_1.2.5-2/include -ID:/devel/emacs/libs/giflib-4.1.4-1/include -ID:/devel/emacs/libs/jpeg-6b-4/include -ID:/devel/emacs/libs/tiff-3.8.2-1/include -ID:/devel/emacs/libs/gnutls-3.0.9/include -ID:/devel/emacs/libs/libiconv-1.13.1-1-dev/include -ID:/devel/emacs/libs/libxml2-2.7.8/include/libxml2' Important settings: value of $LANG: ENU locale-coding-system: cp1252 default enable-multibyte-characters: t Major mode: Org Minor modes in effect: which-function-mode: t global-auto-revert-mode: t show-paren-mode: t cua-mode: t mouse-wheel-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 column-number-mode: t line-number-mode: t transient-mark-mode: t Recent input: C-z C-s c r e a t e C-s c r e a t e SPC u s c r e a t SPC e SPC u s e r SPC f o r t i s SPC i d e n t i f i e d SPC b y SPC f o r t i s ; C-s g r a n t C-s C-s C-s C-s C-s g r a n t SPC d b a SPC t o SPC f o r t i s ; C-c C-c C-c C-c C-c C-c M-x r e p o r t - e m Recent messages: Clock starts at [2013-08-02 Fri 10:41] - showing entire task time. byte-code: Beginning of buffer [13 times] Mark saved where search started [2 times] Mark set Mark saved where search started Auto-saving...done Mark set org-ctrl-c-ctrl-c: C-c C-c can do nothing useful at this location Clock stopped at [2013-08-02 Fri 10:54] after HH:MM = 0:13 Clock starts at [2013-08-02 Fri 10:55] - showing entire task time. Load-path shadows: None found. Features: (shadow sort mail-extr emacsbug message rfc822 mml mml-sec mm-decode mm-bodies mm-encode mailabbrev gmm-utils mailheader sendmail mail-utils sql vc-cvs vc-rcs vc-dir ewoc vc misearch multi-isearch add-log vc-dispatcher vc-svn hideshow help-mode tabify org-table org-clock w32-fullscreen org-wl org-w3m org-vm org-rmail org-mhe org-mew org-irc org-jsinfo org-infojs org-html org-exp ob-exp org-agenda org-info org-gnus org-docview org-bibtex bibtex org-bbdb org ob-tangle ob-ref ob-lob ob-table org-footnote org-src ob-comint ob-keys org-pcomplete pcomplete org-list org-faces org-entities noutline outline easy-mmode org-version ob-emacs-lisp ob ob-eval org-loaddefs format-spec cal-menu calendar cal-loaddefs longlines confluence advice help-fns advice-preload confluence-edit image-file browse-url thingatpt ediff-merg ediff-diff ediff-wind ediff-help ediff-util ediff-mult ediff-init ediff url-http tls url-auth mail-parse rfc2231 rfc2047 rfc2045 ietf-drums url-gw xml-rpc xml doc-view jka-compr image-mode dired goto-last-change warnings server org-exp-blocks org-compat org-macs find-func iimage php-mode etags cc-langs cl cc-mode cc-fonts cc-guess cc-menus cc-cmds cc-styles cc-align cc-engine cc-vars cc-defs speedbar sb-image ezimage dframe easymenu ds-grep derived compile comint ansi-color ring cl-macs gv cl-lib tempo url url-proxy url-privacy url-expand url-methods url-history url-cookie url-domsuf url-util url-parse auth-source eieio byte-opt bytecomp byte-compile cconv gnus-util mm-util mail-prsvr password-cache url-vars mailcap xml-parse doxymacs which-func imenu autorevert paren cua-base cus-start cus-load time-date tooltip 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 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 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 w32 multi-tty emacs)