bug#8248: 23.2; Emacs 23.2 very slow over ssh when vertical-scroll-bar is enabled

[obh]

When vertical-scroll-bar is enabled on emacs 23.2 and used over ssh -X
then switching buffers (^X ^B) takes several seconds. Likewise
scrolling, changing windows etc. is very sluggish. I have a 12/5 Mbps
cable line between work/home with usually 8-12ms ICMP rtt. Plenty of
available bandwidth and CPU.

Emacs feels a lot mot snappy and is usable when starting 'emacs -xrm
'*verticalScrollBars: off'.

I found the following (old) bug report in emacs bug database that
probably describes this bug:

  http://debbugs.gnu.org/cgi/bugreport.cgi?bug=6429

When googling 'emacs ssh latency' there seems to be more people
having this problem and the prevalent advise was to use use server
fonts and not client fonts. I tried to compile emacs with
'--without-xft' but with no visibly speedup.

  
http://groups.google.com/group/gnu.emacs.help/browse_thread/thread/8bf4914f3a7ae7e5
  
http://groups.google.com/group/gnu.emacs.help/browse_frm/thread/bd7e102326bec6b2/dd8706c921a0ef8c?tvc=1#dd8706c921a0ef8c


Kind regards,

Ole Bjorn Hessen


---




In GNU Emacs 23.2.1 (x86_64-unknown-linux-gnu, GTK+ Version 2.10.4)
 of 2011-03-03 on asol1.nm1.telenor.net
Windowing system distributor `The X.Org Foundation', version 11.0.10707000
configured using `configure  
'--prefix=/local/net/arch/linux_x86_64/encap/emacs-23.2''

Important settings:
  value of $LC_ALL: nil
  value of $LC_COLLATE: nil
  value of $LC_CTYPE: no_NO.UTF-8
  value of $LC_MESSAGES: nil
  value of $LC_MONETARY: nil
  value of $LC_NUMERIC: nil
  value of $LC_TIME: nil
  value of $LANG: en_US.UTF-8
  value of $XMODIFIERS: nil
  locale-coding-system: utf-8-unix
  default enable-multibyte-characters: t

Major mode: Lisp Interaction

Minor modes in effect:
  tooltip-mode: t
  mouse-wheel-mode: t
  file-name-shadow-mode: t
  global-font-lock-mode: t
  font-lock-mode: t
  blink-cursor-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t
  line-number-mode: t
  transient-mark-mode: t

Recent input:
<down-mouse-1> <mouse-1> C-x C-b e C-x m q <tab> <M-backspace> 
C-x k <return> y e s <return> C-x C-g M-x r e c <backspace> 
p o <tab> r t <tab> <return>

Recent messages:
For information about GNU Emacs and the GNU system, type C-h C-a.
Commands: d, s, x, u; f, o, 1, 2, m, v; ~, %; q to quit; ? for help.
Making completion list...

Load-path shadows:
/home/o/obh/emacs/cperl-mode hides 
/local/net/arch/linux_x86_64/encap/emacs-23.2/share/emacs/23.2/lisp/progmodes/cperl-mode

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mm-util mail-prsvr gmm-utils wid-edit mailheader canlock sha1 hex-util
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multi-tty emacs)