LBX is a scheme for minimizing bandwidth consumption over X connections. It’s very nice if you want to run RemoteEmacs (which see) on a system which is not in your local network.
See http://www.paulandlesley.org/faqs/LBX-HOWTO.html for general information about LBX.
However, Emacs and LBX don’t seem to be able to cooperate properly, and the Emacs will fatally freeze. http://www.geocrawler.com/archives/3/337/1998/6/0/1846958/ describes the problem. An unverified rumour has it that turning on
x-synchronize will make this problem not appear.
Other ways for accelerating RemoteEmacs exist too, some based on similar, but different systems than LBX (xdpc, nx), some different (ssh compression).
Also, you can run Emacs in an Xterm on the remote system. You lose much of the motivation for running X but it’s still better than “blind” remote access, and LBX (or similar) can be a real lifesaver if your X connections keep getting disconnected because of timeouts or other network flakiness. (But then you could also look into screen(1).)
Hint for LBX with Emacs users: for better performance, turn off the menu-bar (use M-` instead), tool-bar and scrollbars (these often need updating whenever you switch buffers). Use ElScreen or Escreen instead of creating more than one frame (frame switching is slow as well).
Reports of this problem follow. Input from new Emacses, especially from the CVS would be valuable here… and if anyone has seen anything about this on any mailing-list, don’t hesitate to add it here. Also getting more input about other X11 servers than XFree86 would tell where the issue lies.
These setups are known to encounter the problem.
- Emacs 19.34+X11R6 Xsun and XFree86 3.3.2
- Various setups described in the original post, see above.
- Emacs 20.7+XFree86 3.3.6
- It seems still to be current as of Emacs 20.7 and XFree86 version 3.3.6. (Debian 2.2 “stable” distribution -- OK, so that’s not terribly state of the art either.)
- Emacs 22.214.171.124+XFree86 4.3
- I have been using “GNU Emacs 126.96.36.199 (i686-pc-linux-gnu) of 2003-06-26” from the Gentoo app-editors/emacs-cvs package with lbxproxy (XFree86 4.3) for a while now (I update to CVS frequently). My Emacs binary is built with the GTK+2 toolkit. I’ve never experienced anything like problem described above. It may well be that this bug is no longer relevant. -- MatthewKennedy
- Emacs 21.1
- I can confirm that this bug is around as of Emacs 21.1, though it’s infrequent that I encounter it. – JoelHolveck
- Emacs 21.2.1+XFree86 4.2.1+lbxproxy from XFree86 4.1.0
- I tried this yesterday on a setup with (“GNU Emacs 21.2.1 (alpha-debian-linux-gnu, X toolkit, Xaw3d scroll bars) of 2002-03-27 on escher, modified by Debian” running over ssh-tunnel to an i686-pc-linux-gnu with XFree86 4.2.1. The lbxproxy on the Alpha was from XFree86 4.1.0. Didn’t work… what a pity. – tekonivel
- Emacs 20.7.2+Xfree86 4.2.1+lbxproxy from XFree86 4.1.0
- My “GNU Emacs 20.7.2 (alpha-debian-linux-gnu, X toolkit) of Fri Apr 5 2002 on lully modified by Debian” also froze after some time, possibly because i triggered the but with XEmacs connected to the same lbxproxy -- tekonivel
These setups seem to work.
- Emacs 19.34+Exceed
- Also from the original post, see above for a link.
- XEmacs 21.4+Xfree86 4.2.1+lbxproxy from XFree86 4.1.0
- Though X11 select&paste from “XEmacs 21.4 (patch 6) \“Common Lisp\” [Lucid] (alpha-debian-linux, Mule) of Wed Apr 10 2002 on lully” seems to trigger errors
Xlib: unexpected async reply (sequence 0x6ffb)!
lbxproxy: reply seq #0x6ffc > internal seq 0x6ffb
Xlib: unexpected async reply (sequence 0x6ffd)!
invalid SendTagData request: tag 0x91 type 3
- followed by lbxproxy spewing out these
lbxproxy: reply seq #0x6ffe > internal seq 0x6ffd
- when i kill text on this, different Emacs which is not ran over the lbxproxy, the XEmacs hasn’t died yet. The shown sequence numbers increments, but the left is always greater by one.
- Triggering the bug with XEmacs possibly froze the GnuEmacs 20 connected via the same lbxproxy at the same time. If i select text with the mouse in the XEmacs, i get more of those “Xlib: unexpected async reply” errors. – tekonivel