**VRay CRASHES and HyperThreading???**

[strawitz]

Hello,

First I am a new VRay user...and rencently I have been getting severe crashes/freezes when I try to render out an animation (which is basically a camera moving through an environment)...so I ran a series of tests with the hope that I would be able to better isolate the cause of the numerous crashes I have been having with VRay...Well, after numerous parameter changes and various render tests I feel I have perhaps discovered the underlying cause of my problem. It is my belief that the crashes that I've been experiencing are caused by some portion of the displacement calculation in VRay. In order to prove this out, I first disconnected both the MAX and VRay displacements and ran the render tests...and surprise-surprise the entire render completed without crashing...this was only the second time I was able to complete this task. So this meant I was getting closer to the actual cause...so I enabled the VRay displacements once again...removed the MAX displacement modifiers from the stack...added the VRay displacement modifiers...and began the renders again. This time after about 20 frames I got MAX and VRay to freeze at the following point...Building Displacement Raycast Accelerator...The memory usage was 1.58GB (current available memory 2GB) and the CPU usage was 38%...this didn't seem to be problematic. In all my tests over the last few weeks, I had never been able to lock MAX and VRay in this manner so I decided to kill the render and restart it from the crash point. After starting and restarting the render numerious times (every 20 or so frames), I continued to get the following error (UNHANDLED EXCEPTION) and decided to give-up my testing once again.

I expect that the quick answer will be that there has to be something wrong with my system, but I honestly to not believe this as I have been using this system to render using another third party render for almost a year without ever a render crash so it is my feeling that it must be something else between MAX and VRay at least in my working environment.

I hope that the description I have sent you will help in determining what my problem is and possibly how I can solve this aside from not being able to use VRay...I would appreciate any help or assistance anyone can give me concerning this issue.

S Y S T E M S P E C S:

Model: BOXX-S5
Dual Xenon 2.4GHz
Hyperthreading Enabled (NOTE: I have read in the user forum that this was causing some other crashes, but I am as of yet unwilling to disable this unless I know that this is a problem.)
RAM: 2GB
Windows XP Professional (Service Pack 1)
VIDEO: Quadro 4 750 XL BIOS: 4.25.00.29.03

S O F T W A R E S P E C S:

3DS MAX 5.1


Thanks in advance,

Kyle

[RErender]

I think it is as simple as running out of RAM, XP systems die at arround 1.6 to 1.8 GB depending on the processes, Have you tried the 3GB switch?

[strawitz]

I think it is as simple as running out of RAM, XP systems die at arround 1.6 to 1.8 GB depending on the processes, Have you tried the 3GB switch?

RErender...

Thanks for the reply...I've had this posted in the bug area for about a week now and no one has responded...Anyway are you talking about physically adding more RAM to my system or adjusting some parameters in XP to create more virtual memory...I appreciate the insight...

Just to let you know the system I've been using has "plowed" through more complex scenes using "another" render with no problems whatsoever so it seems a bit strange that a lighter scene would give me such errors...

I ran a test last night by disabling the hyperthreading in the Task Manager Set Affinity section and it rendered some frames no problem...So I set off the entire sequence overnight and when I woke-up VRAY and MAX were frozen so I killed the process. I'm starting to think that there is something about the hyperthreading and VRay. So this morning before I left for work, I went into the BIOS and disabled the hyperthreading as a last resort in trying to bring some stability to VRay...


I think I'm sort of out of gas on trying to make this work at least on my machine...

Thanks for your help...

Kyle

[nully]

try this http://www.chaoticdimension.com/foru...t=switch#37796

Hyperthreading shouldnt cause problems, this tweak affects the way windows xp deals with memory.

[vhunter]

We have same problem with VIZ 4.2 and VRAY running animations on Dual XEON Processor systems with Hyperthreading enabled. It does not work, believe me we have tried everything. You must disable hyperthreading before rendering an animation. (which I constantly forget to do)

However, rendering single images does not seem to be a problem.

Vince

[Da_elf]

in task manager it says im using 1.6gb memory on my dual xeon 2.8ghz with hyperthreading activated and 1gb physical ram. and ive never had a single crash when rendering. not a lock up. nor anything like that for that matter. For you to say there is a hyperthreading problem with vray you would need to see 100% crashes with every hyperthreading system. but since the results are not constant (tonnes of people in here have no problem with HT) then it means the problem isnt HT

[Syclone1]

Yup, Ive said it before and I'll say it again. Running dual Xeons here with HT enabled for close to a year. with no troubles relateing to HT at all.

-dave

[tom schuelke]

Hmm

i think this problem allways is caused because of the fantastic programmstructure of our all much loved mr gates.

mean, windows in its ini is set to about 1.5 gigabyte available ram. which is a good value for usual winword tasks.

so maybe two solutions

first, deinstall max and vray, and search a job as a typist.

otherwise better try the gigabyte switch as told above. this enables vray to use the whole memory of your system without chrashes.

after installing the gigabyte switch, we where able to use memory up to 3.2 Gig.

also try to bring down for example settings, if you use displacement.

At last dont take me too serious,

and at last at last, the new 1.5 will overcome with all memory problems, if you use the new dynamic raycast accellerator for the cost of a bit of speed.

good luck

Tom

www.lichtecht.de

[TRGraphics]

Same here. Never had a problem with hyperthreading on my dual 2.8 system.

Tony

[vhunter]

Ours only crashes with viz 4.2 and with hyperthreading enabled on dual xeons. We upgraded one of our dual xeons to max 6 and hyperthreading is working great. Its only crashing on the viz 4 station, but i'm not brave enough to try the 3gb memory tweak, yet, maybe next week if we get a break in deadlines.

Vince

[cocolas]

Same here. Never had a problem with hyperthreading on my dual 2.8 system.

Tony

same here....no probs whatsoever....

paul.

[strawitz]

Guys,

THANKS for the replies...Just to keep you posted on my findings and tests. I disabled HT on my home machine and for the first time I was able to get the entire sequnce to render...mind you that was only a 720x486 version on a scene with 202,041 polys (displacement and irradiance maps). In the meantime, I started another render here at the office (totally different system with 2GB of ram...MAX 5.1 etc.) with HT enabled and it locked-up just as it did at the house. Now this is on two different systems...So last night before I went to bed I doubled the resolution and re-started the render...When I woke up, it was still chugging along...at least it hadn't crashed or locked up as it did in the past...so I was feeling a little better about my test results.

Now to say VRay doesn't have a problem with HT seems a bit "curious" to me...Yes perhaps it's all a Windows XP thing, but I have "plowed" through other scenes 5x more complex using another 3rd party render on both machines with NEVER a crash or a lock-up...so it's my belief that there is some sort of issue in it's memory management with regards to hyperthreading on particular machines...to cursorily dismiss this as an isolated incident doesn't seem reasonable since it seems others have encountered the same problem with a similar solution.

I would hope that there would be a more substantial and permanent fix to issues such as these without having to "hotwire" Windows which could cause other problems when working with deadlines and other software.

I would appreciate any other insight or "official" information regarding a solution for these type of errors which could hopefully allow us to use VRay on a consistant and continued basis.

Thanks,

Kyle

[vlado]

There have been some reports about problems with hyperthreading; we have a dual HT machine here at Chaos Group, however it has not exhibited any problems when running VRay - so the issue remains unclear and we will have to look at it in more detail.

Best regards,
Vlado

[Smalerbi]

Kyle, I feel your pain. I’ve been experiencing the same set of issues for some time. The problem arises more with large exterior scenes and especially when attempting an animation. I have no idea if it is related to HT and I have never attempted to disable HT because I have no idea how do to it. I have seen some very large scenes rendered in Vray and I have no idea how they are doing it. They must be pulling a magical rabbit out of the hat. Until the Vray team can figure out the issues, I have an expensive plug-in I can not rely on or use. Perhaps some of these issues will be addressed in the new release………whenever that will be. I hate so sound cynical, but I can no longer afford to have my clients disappointed in my lack of performance because the rendering engine I have chosen continues to fall short. I spend more time testing and attempting to find a work around than I do working on the project. My only other option is to digress back to scanline or move forward with another third party rendering engine. Stability and reliability is everything!

Thanks for allowing me to be bend your ear.

Scott.

My work station is a Dual 2.8 Xeon with 2gig of ram. W2K server with service pack 3

[Da_elf]

you need to go into your BIOS on boot . im not sure exactly where you would find it since different BIOS's would have it in different places i guess. but the hyperthreading switch might be in there

i realise we have alot of HT supporters and alot of HT haters when it comes to vray. since there can only be so many types of HT chips and im sure there are prople with 2.8GHz HT chips who cant get it to work. and alot of people like myself who can get it to work. how about we dont focus on the chip as the problem. could it possibly be the motherboard that is messing things up. maybe different motherboards perform better or worst with HT technology. my mobo for instance is a supermicro X5DAE. if there is anyone else using this who is havig vray trouble let me know.