Re: remote X11/GNU emacs/ssh: Incredible slowness loading libs

[frobware inc]

"David Abrahams" <david.abrahams@rcn.com> wrote in message 
news:<an804g$8d3$1@bob.news.rcn.net>...
> "Krishnakumar B" <kitty@cs.wustl.edu> wrote in message
> news:dmlu1k8cwsc.fsf@charanga.cs.wustl.edu...
> > On Sunday, 29 September 2002, "David Abrahams" wrote:
> > > I've been doing some work on remote machines on the other U.S. coast
> > > recently, and have noticed strange and horrible delays associated with
> > > running GNU emacs in an X window. At first I thought the problem was the
> > > speed of traffic associated with X11, but I don't think so any more. The
> > > reason I say these delays are strange is that they seem to be worst when
> > > emacs is loading libraries (especially during startup), or just when
>  it's
> > > trying to respond to "C-x C-f" the first time. On some machines, it
>  takes
> > > literally minutes to give me the "find file:" prompt. I don't see the
>  same
> > > problems when running "emacs -nw" in an xterm (that just blasts along
>  like
> > > crazy), so it can't be having trouble loading the libraries. I don't see
> > > anything this bad when running Xemacs, so I doubt there's a real problem
> > > with the X11 GUI stuff. Can't imagine what the problem is. Any ideas?
> >
> > Enable ssh compression. It helps a lot.
> 
> Makes absolutely no perceivable difference. However, there is an enormous
> amount of network traffic going by, as I can see by the flashing light on my
> NIC. This happens any time a new emacs mode (library) loads on the remote
> machine. What in the world could it be accessing on my local machine? All
> that handshaking, just as emacs starts up?!?
> 
> I heard some rumour that you can work around this with .Xauthority, but I'm
> tired of diddling around with things I don't really understand, and I still
> can't understand why there should be any difference between emacs -nw and
> emacs when it comes to loading libraries.
> 
> still-baffled-ly y'rs,
> dave


I happened to run into this thread in my quarterly scan of the group.


I had/have the same problem. I dial into a work machine, and can run
emacs (reasonably OK), displaying stuff on my laptop. However, at
times I also need to ssh into another machine  (over vpn, from my work
machine), and this runs into all the problems that David describes. It
takes CxCf about 1 minute to respond. Xemacs isn't so bad, and the
xterm itself works just fine. So it is something to do with gnu emacs.
I tried emacs verion 19/20/21, all exhibit the same problem. Since I
couldn't figure out what was going on, and since I thought this was a
problem unique to my environment (apparently not), I switched to
`emacs -nw', which works just fine. I prefer to use gnu emacs over
xemacs since I am used to the former.

My best guess is that the authentication handshake between emacs, and
ssh/remote-xserver is somehow causing incredible latencies. (I turned
compression on, and that did not help either.)

What blows my mind is that emacs should take so long to load lisp
libraries when run over an ssh/vpn/remote-xserver connection.