On Sun, Feb 08, 2009 at 06:42:05PM +0100, Simon Schmidig wrote: > Le dimanche 08 février 2009 à 09:08 -0600, Scott Balneaves a écrit : > > > You still haven't tried the most important test. > > > > Take another full workstation, and log in. Then ssh -X <ltspserver> > > <javaapp> > > which starts the java app on the remote ltsp server, but displays it > > locally, > > just like an LTSP workstation. > > Test 1 : ssh -X <ltspserver> <javaapp> > *slow* like LTSP > Test 2 : nx <ltsperver> ; <javaapp> > *fast* like on local sur le <ltsperver>
This is an important result. Since NX sets up a virtual X server locally, then ships image delta's over the wire, whereas ssh -X is forwarding the X remotely, theres some resource that the remote X isn't getting access to, that the local virtual X server is. A further test would be: (on the local workstation, note that your X server must *not* be running -notcp) xhost + (then, ssh'ing into the LTSP server) export DISPLAY=<workstationip>:0 javaapp This runs the java app the same as specifying DIRECT_X = True in lts.conf. i.e. the display variable is simply set to point to the workstation. If *it* runs slowly, and I suspect it will, then the problem is some kind of interaction between a java program, and a *remote* X server. Now, there's been a big change in X in the last year or so, namely with the removal of the old, standard X libs, and the replacement with xcb: http://xcb.freedesktop.org/ This, certainly, is one place to start looking for a possible slowdown. Another place would be the XRENDER extention. LTSP installs a minimal amount of fonts in the chroot, and extra fonts are picked up via the XRENDER extention, which for the most part, seems to work flawlessly. I'm wondering if that might not be causing a problem. I know some people are working on a java "test program" that's a simple program to use for testing of this problem. I'm interested in seeing that. Scott -- Scott L. Balneaves | Today's weirdness is tomorrow's reason why. Systems Department | -- Hunter S. Thompson Legal Aid Manitoba | ------------------------------------------------------------------------------ Open Source Business Conference (OSBC), March 24-25, 2009, San Francisco, CA -OSBC tackles the biggest issue in open source: Open Sourcing the Enterprise -Strategies to boost innovation and cut costs with open source participation -Receive a $600 discount off the registration fee with the source code: SFAD http://p.sf.net/sfu/XcvMzF8H _____________________________________________________________________ Ltsp-discuss mailing list. To un-subscribe, or change prefs, goto: https://lists.sourceforge.net/lists/listinfo/ltsp-discuss For additional LTSP help, try #ltsp channel on irc.freenode.net
