Slow performance over VPN/cable modem

Slow performance over VPN/cable modem

[Bruce A. Hamilton]

XP Pro SP1, Pentium 2.66 GHz, 1 GB memory.

I am running the latest cygwin including XFree86 4.3.0.

Performance connecting to my workplace via VPN over cable modem is 
painfully slow, similar to what I used to see running X over dialup years 
ago. I'm running a local window manager fvwm2 then "ssh -X" to hosts at 
work via my local xterms.

The app I'm most interested in is Veritas NetBackup 4.5 jnbSA, which is 
written in Java and not exactly speedy even at work, but at work we are 
talking a couple of seconds to refresh the screen, versus nearly a minute 
for the tiniest changes at home.

My Internet connection in general is very fast, on the order of 2 Mb/sec, 
and I get excellent response over my VPN to work using vanilla text apps 
and MS Outlook.

Thanks for any suggestions. I'm quite sure this in an X issue. Wasn't MIT 
supposed to be working on "low-bandwidth X" years ago?

Three years ago I had the good fortune to be able to use Graphon's 
Go-Global to channel X over dialup and was VERY impressed.

More recently I played a little bit with VNC and it seemed to have its own 
performance issues so I have no pursued it further at this time, but I'll 
consider it if you recommend it.

--Bruce (Bruce Hamilton, Redondo Beach, CA)
bhami@pobox.com
http://bhami.com/

Re: Slow performance over VPN/cable modem

[David Fraser]

Bruce A. Hamilton wrote:

> XP Pro SP1, Pentium 2.66 GHz, 1 GB memory.
>
> I am running the latest cygwin including XFree86 4.3.0.
>
> Performance connecting to my workplace via VPN over cable modem is 
> painfully slow, similar to what I used to see running X over dialup 
> years ago. I'm running a local window manager fvwm2 then "ssh -X" to 
> hosts at work via my local xterms.
>
> The app I'm most interested in is Veritas NetBackup 4.5 jnbSA, which 
> is written in Java and not exactly speedy even at work, but at work we 
> are talking a couple of seconds to refresh the screen, versus nearly a 
> minute for the tiniest changes at home.
>
> My Internet connection in general is very fast, on the order of 2 
> Mb/sec, and I get excellent response over my VPN to work using vanilla 
> text apps and MS Outlook.
>
> Thanks for any suggestions. I'm quite sure this in an X issue. Wasn't 
> MIT supposed to be working on "low-bandwidth X" years ago?
>
> Three years ago I had the good fortune to be able to use Graphon's 
> Go-Global to channel X over dialup and was VERY impressed.
>
> More recently I played a little bit with VNC and it seemed to have its 
> own performance issues so I have no pursued it further at this time, 
> but I'll consider it if you recommend it.
>
> --Bruce (Bruce Hamilton, Redondo Beach, CA)
> bhami@pobox.com
> http://bhami.com/
>
>
I would recommend trying the latest version of VNC (4.0b4) from 
realvnc.com if you are having bandwidth constraints, though there may be 
other suggestions about X...

David

Re: Slow performance over VPN/cable modem

[Ruth Ivimey-Cook]

Bruce A. Hamilton wrote:

> XP Pro SP1, Pentium 2.66 GHz, 1 GB memory.
> I am running the latest cygwin including XFree86 4.3.0.
>
> Thanks for any suggestions. I'm quite sure this in an X issue. Wasn't 
> MIT supposed to be working on "low-bandwidth X" years ago?

Yes, they did and it's been available for a while now. You run the app 
"lbxproxy" on the local end (home) set up to connect to your work 
server, and then do a normal X connect to the local server connection 
that is presented by lbxproxy.

This assumes the normal case, that the remote server includes the LBX 
server extension.

Hope this helps.

Ruth

Re: Slow performance over VPN/cable modem

[Alexander Gottwald]

On Fri, 21 Nov 2003, Bruce A. Hamilton wrote:

> XP Pro SP1, Pentium 2.66 GHz, 1 GB memory.
> 
> I am running the latest cygwin including XFree86 4.3.0.
> 
> Performance connecting to my workplace via VPN over cable modem is 
> painfully slow, similar to what I used to see running X over dialup years 
> ago. I'm running a local window manager fvwm2 then "ssh -X" to hosts at 
> work via my local xterms.

Afair cable modems have a high latency. 

> The app I'm most interested in is Veritas NetBackup 4.5 jnbSA, which is 
> written in Java and not exactly speedy even at work, but at work we are 
> talking a couple of seconds to refresh the screen, versus nearly a minute 
> for the tiniest changes at home.

Does this application use Swing? If so then the slow performance is not a 
problem of X11 but a design error of Java/Swing. All graphicsoperations in 
Swing are localy drawn into a bitmap and the bitmap is then transferred to 
the xserver. This is much more expensive than letting the xserver perform
the drawing operations.

> Thanks for any suggestions. I'm quite sure this in an X issue. Wasn't MIT 
> supposed to be working on "low-bandwidth X" years ago?

They never thought of Java.

bye
	ago
-- 
 Alexander.Gottwald@s1999.tu-chemnitz.de 
 http://www.gotti.org           ICQ: 126018723

Re: Slow performance over VPN/cable modem

[Takuma Murakami]

Have you tried "ssh -C -X" ?

Takuma Murakami (murakami@ipl.t.u-tokyo.ac.jp)

Re: Slow performance over VPN/cable modem

[Igor Pechtchanski]

On Sat, 22 Nov 2003, Bruce A. Hamilton wrote:

> At 06:25 AM 11/22/2003, you wrote:
> >Bruce A. Hamilton wrote:
> >
> >>XP Pro SP1, Pentium 2.66 GHz, 1 GB memory.
> >>I am running the latest cygwin including XFree86 4.3.0.
> >>
> >>Thanks for any suggestions. I'm quite sure this in an X issue. Wasn't MIT
> >>supposed to be working on "low-bandwidth X" years ago?
> >
> >Yes, they did and it's been available for a while now. You run the app
> >"lbxproxy" on the local end (home) set up to connect to your work server,
> >and then do a normal X connect to the local server connection that is
> >presented by lbxproxy.
> >
> >This assumes the normal case, that the remote server includes the LBX
> >server extension.
>
> Thanks, but I get the following error
>
>   % lbxproxy
>   _LBXPROXYTransmkdir: Owner of /tmp/.X11-unix should be set to root
>
> If I try to hack up a bogus root user by adding it to the cygwin
> /etc/passwd, then chown says
>
>   % chown root .X11-unix
>   chown: changing ownership of `.X11-unix': Invalid argument
>
> which is different than if I try to chown it to some non-existent user:
>
>   % chown foo .X11-unix
>   chown: `foo': invalid user
>
> ???

The bogus root user should nevertheless have a real SID (and a UID of 0).
I suggest copying the SYSTEM entry and changing the username to root and
UID to 0 and making sure it appears before the real SYSTEM entry in
/etc/passwd (note that this may present problems with some apps, notably
apache, that hardcode the SYSTEM UID as 18 on Cygwin).
	Igor
-- 
				http://cs.nyu.edu/~pechtcha/
      |\      _,,,---,,_		pechtcha@cs.nyu.edu
ZZZzz /,`.-'`'    -.  ;-;;,_		igor@watson.ibm.com
     |,4-  ) )-,_. ,\ (  `'-'		Igor Pechtchanski, Ph.D.
    '---''(_/--'  `-'\_) fL	a.k.a JaguaR-R-R-r-r-r-.-.-.  Meow!

"I have since come to realize that being between your mentor and his route
to the bathroom is a major career booster."  -- Patrick Naughton

Re: Slow performance over VPN/cable modem

[Bruce A. Hamilton]

At 06:25 AM 11/22/2003, you wrote:
>Bruce A. Hamilton wrote:
>
>>XP Pro SP1, Pentium 2.66 GHz, 1 GB memory.
>>I am running the latest cygwin including XFree86 4.3.0.
>>
>>Thanks for any suggestions. I'm quite sure this in an X issue. Wasn't MIT 
>>supposed to be working on "low-bandwidth X" years ago?
>
>Yes, they did and it's been available for a while now. You run the app 
>"lbxproxy" on the local end (home) set up to connect to your work server, 
>and then do a normal X connect to the local server connection that is 
>presented by lbxproxy.
>
>This assumes the normal case, that the remote server includes the LBX 
>server extension.

Thanks, but I get the following error

  % lbxproxy
  _LBXPROXYTransmkdir: Owner of /tmp/.X11-unix should be set to root

If I try to hack up a bogus root user by adding it to the cygwin 
/etc/passwd, then chown says

  % chown root .X11-unix
  chown: changing ownership of `.X11-unix': Invalid argument

which is different than if I try to chown it to some non-existent user:

  % chown foo .X11-unix
  chown: `foo': invalid user

???

--Bruce (Bruce Hamilton, Redondo Beach, CA)
bhami@pobox.com
http://bhami.com/