On Tue, 2004-09-28 at 10:47, Gino LV. Ledesma wrote: > Indeed the local session is faster (it is a Dual Xeon setup after all, > hehehe). The catch is this: > - Using local-applications (on a Celeron 233) performance is "almost as good" > - Using VNC (on a Pentium Classic): performance is also as good as the preivous > - Using server-side LTSP / Remote X (on a Celeron 233): performance > is really bad
When you say performance is horrible - you mentioned slow TIFF rendering for one thing. Is general workstation performance also bad - mouse movement, focus changes, bringing windows to the front, etc? Or is it mostly/entirely TIFF rendering? It's worth understanding that X11 sends image rendering instructions over the wire uncompressed, something that irritates me a lot even though I understand how it came about. Tunnelling X via SSH will help, but at the cost of considerable client and server CPU time. This _might_ be what's behind the improvements you see with TightVNC - it will intelligently compress the image as it sends it, without encrypting it, so it's quite "cheap" for the client to decode and display it. It may well be worth your while to check out NX (http://www.nomachine.com/), who attempt to address this problem. I haven't tried it myself (I'm doing OK with raw X11) but have heard good reports. No idea about LTSP integration though. When it comes to isolating the bottleneck, have you tried running good 'ol x11perf? While its benchmarks are in many ways severely outdated it can still be quite informative. I've also gained useful information from getting a tcpdump of a testing session (on an isolated LAN) then graphing that for throughput in ethereal - it's easy to spot if the network is pegged at any point, spot odd drop-outs, etc. You do need to keep careful track of what you did when in the testing session though. This thread has been broken several times and I didn't have time to dig back to find it all so I hope I haven't repeated anything. -- Craig Ringer ------------------------------------------------------- This SF.Net email is sponsored by: YOU BE THE JUDGE. Be one of 170 Project Admins to receive an Apple iPod Mini FREE for your judgement on who ports your project to Linux PPC the best. Sponsored by IBM. Deadline: Sept. 24. Go here: http://sf.net/ppc_contest.php _____________________________________________________________________ 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
