Home.... | log in.... | Pub my question! | Sign-up....
Java-index >> Desktop >> Sun Ray Software - General Discussion

Sun Ray 4 update 1 beta on RHEL4 Update 3 flaky display...

We've installed Sun Ray 4 Update1 on a RHEL4 update 3 host (dual-Xeon 3.8Ghz, 2GB mem), and we're noticing that displays paint a bit slower than what we saw on Solaris 8 (granted that was Sun Ray Server 3.1 we tried before). You can watch the desktop background paint when you minimize a window, and the Gnome terminal characters also "scroll" in the same poorly painted fashion. Funny, xterminals are very snappy and scroll very quickly.

The libc_ut.so preload issue is also a pain...the workaround specified in the readme is 'ok', but not acceptable for deployment use.

I never reviewed the output of utcapture to see packet loss, but we're seeing significant packet loss (%15+)

[705 byte] By [kevinlange] at [2007-11-26 9:43:30]
«« Problems with deleted domain
»» Timestamp with zeroed time from DataProvider
# 1

If your 15% packet loss is happening for a large number of packets (losing 1 packet out of a 6-packet window very occasionally isn't a problem, losing 1 packet out of *every* 6 consistently is a big problem) then that's more than enough to explain the slow painting. You need to figure out why that's happening.

One likely cause is a duplex mismatch between a switch port and the equipment plugged in to that port. Make sure that everything is set to auto-negotiate and that the actual result is correct. If for some reason you need to force a speed or duplex setting then make sure you do that at both ands of the link and make sure that the link is actually operating in that state.

Another possibility is that if you have a gigabit link from the server to the switch, the switch might not be buffering UDP traffic and could be discarding packets before they can be pushed out at 100Mbps to the Sun Rays. If your switch allows control over UDP buffering then turn it up high.

OttoM.

ottomeister at 2007-7-7 0:44:14 > top of Java-index,Desktop,Sun Ray Software - General Discussion...
# 2

We tested on Solaris 8, with Sun Ray server 3.1, and I don't remember seeing any screen artifacts or sluggishness when rendering. So, we're not sure what factor is causing our problems; Linux or the beta server software.

Our fairly well-seasoned network architect is not sure what feature in Cisco IOS that would manage udp packet buffering. He has noticed that there seems to be some issue with buffer overruns with regards to udp traffic between two endpoints; one on gigE and the other on 100MB ethernet.

Here is the output of utcapture.

00144f102d62 200608281304591483354305194114578884424.980

00144f102d52 20060828130514556704255871836519758811.681

00144f102d52 2006082813052955701085587893687322342.316

00144f102d62 200608281305291484403305470114667124626.311

00144f102d52 20060828130544557313055911537179902210.788

00144f102d62 200608281305441484896305551114711853816.430

00144f102d62 200608281305591485491305704114758080225.714

00144f102d52 2006082813061455744845592233730129747.976

00144f102d52 20060828130629557649255954437473297215.986

00144f102d62 200608281306291486584305926114859463220.311

00144f102d52 20060828130644557903755987837708982213.124

00144f102d62 200608281306441487196306035114915697817.810

00144f102d62 200608281306591487886306206114972708024.783

00144f102d52 2006082813071455806925600383785896169.668

00144f102d62 200608281307291489312306517115105800621.809

00144f102d52 20060828130744558462456030938264064613.389

00144f102d62 200608281307441490240306858115172391236.746

00144f102d62 200608281307591490949306951115242814413.117

00144f102d62 200608281308141492025307295115327762031.970

00144f102d52 20060828130829558778256061338546761814.159

00144f102d52 20060828130844558969556087738713664013.800

00144f102d62 200608281308441493540307570115476767218.152

00144f102d62 200608281308591494433307801115552043625.868

00144f102d52 2006082813091455908995609603881767666.894

00144f102d62 200608281309141495218307932115627096016.688

00144f102d52 20060828130929559610756202039277114220.353

00144f102d52 2006082813094455975245621173940782026.845

00144f102d62 200608281309441496838308391115766370628.333

00144f102d62 200608281309591497594308593115830475426.720

00144f102d52 20060828131014559993056240739625621412.053

00144f102d62 200608281310141498425308830115899649028.520

00144f102d52 2006082813102956014815625083976865706.512

00144f102d52 2006082813104456027165625663987938484.696

00144f102d62 200608281310441499814309230116019557628.798

00144f102d62 200608281310591500496309395116078681824.194

00144f102d62 200608281311141501184309548116140318022.238

00144f102d52 2006082813112956056095625674019250480.056

00144f102d52 2006082813114456065715625844028120061.767

00144f102d62 200608281311441502934310004116299297226.057

00144f102d52 2006082813115956084755626624048352344.097

00144f102d62 200608281311591503806310215116375247824.197

00144f102d62 200608281312141504681310431116451091624.686

00144f102d52 20060828131229561427356372141009068418.265

00144f102d52 2006082813124456161215637644121074822.327

00144f102d62 200608281312441506358310861116602517025.641

00144f102d52 2006082813125956215365639554187502663.527

00144f102d62 200608281312591507691311289116710757632.108

00144f102d62 200608281313141508814311642116801305231.434

00144f102d52 2006082813132956236255641144209065907.611

00144f102d52 2006082813134456246575641474218584403.198

00144f102d62 200608281313441510410311996116950840822.180

00144f102d62 200608281313591511176312115117026422615.535

00144f102d62 200608281314141512280312426117120039628.170

00144f102d52 20060828131429563284756511643076538221.330

00144f102d62 200608281314441513846312706117276382817.880

00144f102d52 20060828131529564257356577744176735613.327

00144f102d52 2006082813154456445825658914438558225.674

00144f102d52 2006082813164456482255660234474078326.477

00144f102d52 2006082813172956542625664764539308529.369

00144f102d52 2006082813174456562605665434561622703.353

00144f102d52 2006082813175956573795665894571627844.111

00144f102d52 2006082813191456611185665904605468400.081

00144f102d52 2006082813194456625135666984618368907.742

00144f102d52 2006082813195956645765668154640006385.671

00144f102d52 2006082813204456672535669444666008669.348

00144f102d52 2006082813231456780895670504781777744.459

00144f102d52 2006082813235956830405671664837336407.983

00144f102d52 2006082813241456850085673014856725446.860

00144f102d52 2006082813255956958085673864981903101.615

00144f102d52 2006082813261456980775674535006758042.953

00144f102d52 2006082813265957002415674915026337243.011

00144f102d52 20060828132714570218356773050435908612.307

00144f102d52 2006082813325957172805677385176697220.483

00144f102d52 2006082813331457182755677535185435161.508

00144f102d52 2006082813341557238825677775233755380.709

00144f102d52 20060828133445572815556811652727857411.507

00144f102d52 2006082813351557301435681725292991062.817

00144f102d52 2006082813353057316685682995306627028.328

00144f1026c8 2006082813354547609546607778657639709.091

00144f102d52 20060828133545573736956958153573963622.487

0003bad75bd0 200608281336151249929013948364207.642

00144f102d52 20060828133615573930056980653744444811.652

00144f102d52 2006082813363057414255699295395415485.788

00144f102d52 2006082813371557439955699475420068441.116

00144f102d52 2006082813374557464635699975442609083.943

00144f102d3d 2006082813381530551081084060209354616010.145

00144f102d52 20060828133815574830157019254590815410.609

00144f102d3d 200608281338303056566108406320949455100.206

00144f102d52 2006082813383057512105704685486532049.488

00144f102d52 2006082813384557532115704805503329620.600

00144f102d3d 200608281339003057882108408020962429441.292

00144f102d3d 200608281339153059069108409020973327260.842

00144f102d52 2006082813391557544685705065514339962.068

00144f1028a8 200608281339302323282668668189362643219.773

00144f102d3d 200608281339303060197108410220983674181.064

00144f102d52 2006082813393057556475705335524732722.290

00144f1028a8 200608281339452333938673079190102229441.395

00144f102d3d 2006082813394530627101084358210054308810.187

00144f102d52 2006082813394557568975705995535320205.280

00144f102d62 200608281339451551908327034120158588239.386

00144f102d62 200608281340001597694344333123813363437.782

00144f1028a8 200608281340152334755673195190174842014.198

00144f102d3d 200608281340153063580108436521012714100.805

00144f102d52 2006082813401557579845706385544601283.588

00144f102d62 200608281340151615153350821125217124437.161

kevinlange at 2007-7-7 0:44:14 > top of Java-index,Desktop,Sun Ray Software - General Discussion...
# 3

We've also tested on Sun Ray 3.1 on RHEL 3 update 6, and results are the same. We've been investigating and tweaking various Cisco switch settings regarding traffic congestion, but the results are the same.

We're going to try to eliminate the specific model of cisco gear (WS-3560 & IBM BladeCenter Cisco switch module) to see if that is the ultimate source.

fezmonger at 2007-7-7 0:44:14 > top of Java-index,Desktop,Sun Ray Software - General Discussion...
# 4

SOLVED: As it turns out, our problem was completely related to GigE path being funneled down to 100MB ethernet uplink on the workgroup switch that services the Sun Ray DTUs.

So our server's NIC is GigE, connected to a local cisco GigE switch, in turn connected to a core Cisco Catalyst 6500 switch. The Sun Ray DTUs are connected to a 3560g switch, which is connected to the core 6500 switch with a 100MB uplink. This is the problem. The 6500 was dropping packets on the 100MB uplink as the 100MB uplink could not keep up with the traffic. When we changed the 100MB uplink to GigE, packet loss as reported by utcapture was minimal, and visible behaviour showed few if any artifacts.

fezmonger at 2007-7-7 0:44:14 > top of Java-index,Desktop,Sun Ray Software - General Discussion...
Desktop
Sun Ray Software - General Discussion

Desktop New Topic

Desktop Hot Topic

Desktop

All Classified