hyperthreading followup

We have been rendering out a series of hq animations over the past week. Every so often, we experienced the same issues as what many people on the forum have obviously experienced, namely random hangs after the ‘static raycast’ thing.

It has been giving us major grief as when this happens to a pc overnight, we loose rendering power from that machine until it is reset in the morning.

We have 6 Dual Xeon 3GHz with 2GB ram - all Tyan boards, all custom built for rendering.

The hanging was becoming a pain, so I decided to disable HT in the bios.

Hey presto, I now haven’t had a crash since 1pm yesterday!

Could the Chaos team please bring everyone up-to-date with this. There is clearly an issue here. Its been difficult to pin down, but obviously HT in our case has, touch wood, solved the problem.

*Could* there be an issue with HT, Max6 and Vray (1.09…r)?
*Has* it been thoroughly tested by the Chaos team?

Tricky

maybe it has something to do with the board type or the xeon cpus.
i have two normal (not xeon) HT enabled cpus that never hang. (vray 1.09)

Have you tried with animation? Saved IRMAPS? Complex scenes?

It could just be a XEON thing.

Anyone else have non-xeons but *with* the hanging issue?

i have xeons but havent tried animation yet … and it has not hung ever while rendering

our Xeons had these problems…we disabled HT and its rendered 1000’s of frames since with 0 problems.

Unfortunately our other machines dont have HT on them so we cant test to see if its just normal P4 or Xeons that may cause the issue.

Also, we had this problem on stills once in a blue moon when using HT, but i guess animations may show the problem up better.

I would be interested to know if HT works better on the betas…we’re using 1.09 at the moment.

Chaos - any comments?

It appears that VRay is NOT stable with HT. I suggest people with deadlines switch HT off in their BIOS.

I’ve posted this before and i will do it again in this thread.
We also have had these problems and are currently running without HT.

We also would like to see this resolved.

Erik

I have had a few problems as well while trying to render a short animation.

(2)Zeon 2.8
PC_DL Asus motherboard - Hyperthreading enabled
2 gig Corsair Extreme memory
Nvidia Quadro 1100 card

No overclocking on anything in my system. I rendered the scenes with hyperthreading off and it went fine. Except that it took a fair amount longer than it should have because of the performance hit I get when it is turned off.

Hopefully this will be addressed in 1.5! It appeared to be a random problem for us at first but now it appears to be a bug.

Tony

Perhaps this thread should be moved to the ‘BUGS FORUM’.

Just wanted to chime in and say I haven’t experienced any problems between VRay and my Dual Xeon 3.2’s with hyperthreading enabled. It’s a BOXX system (not one I built myself). Been running it since April with no hiccups.

I think it uses a Supermicro MB and it has a QuadroFX1100 video card with 2 GB RAM.

Jeff

our xeons are dells…it failed on the first one…we’ve disabled it on the others because we’re too busy to lose frames overnight at the moment.

I have a dell Precision workstation as well w/ hypertreading enabled, and haven’t had a problem w/ it…

paul.

what i see is that there is a problem with :

animation rendering with backburner on render farm of 2xeon with ht on

on my wstation (2xeon) never had problem

but some time on the render farm some nodes are hanging

don’t know if this is ht problem or 2xeon problem

Ive been thinking the same as Tammo, where it could be an issue witha certain board/chipset. I have 2 dual 2.8ghz Xeons Ive built on Supermicro boards and they both have renderd 1000’s of frames each with 0 issues relating to HT. The issue mostly seems to be with Dell, Asus and Tyan boards, if someone with a Supermicro board is having HT realted problems please post your results. Also in order to figure what is going on the best thing to do is if your having what you think to be HT related issues please post the machine specs including chipsets, bios revs, brand and type of ram…

Im not saying that the issues are not caused by HT but with more info I think we mite be able to narrow it down to a specifc problem.

Also if someone has a scene that will NOT render for them with HT enabled I would like to try render them on my xeons in hopes of narrowing down the issue. Just PM me if you wish to try this.

-dave

I think Serge is on to something,

We have one supermicro and two dell poweredge servers and both give problems when rendering animations with HT enabled. So i think the hardware issue could be brought back to just the dual xeon processor on a renderfarm.

Erik

our system that caused problems

Dell Precision 450, dual 2.8 ghz 512k cache, 1 ghz ram, win xp (not service pack 1) rendering under backburner from max 5.1

You’ve got me worried, I’ve just bought a new dell dual xeon (Precision 470) with HT enabled. I’ve not had any hangs rendering stills and I’m yet to try rendering an animation, maybe I’ll set one going over the weekend. If I do I’ll report back any problems.

A quick search on google showed that VRay is not the only program experiencing problems with HT, it’s not even restricted to Windows as Linux users are also having similar issues.

Example:

http://softwareforums.intel.com/ids/board/message?board.id=42&message.id=476

Microsoft and Intel have admitted that there is a bug in Windows inplementation of HT but it appears to affect performance rather than cause software freezes. This has been fixed in XP SP2, apparently.

http://notebookforums.com/archive/index.php/t-4159.html
http://www.xbitlabs.com/news/cpu/display/20030616011726.html

Dan

HT Prob On 5 all 5 of my machines

I have x5 PC-DL Asus dual 3.06 and have to turn HT off for complex vray gi scenes, all is fine if you dont use GI. Its def a Vray prob not a hardware prob.

16 Dual 2.8’s w/HT enabled here, few problems (well no more than with Max scanline) with heavy animation rendering with GI and V-Ray. Most problems can be traced to network traffic issues not HT.

Generic systems based on SuperMicro x5dal-g