Running Low on Memory while Rendering" error

[pashley]

In the hopes of getting faster render times we have been testing an IBM Intellistaion with dual Xeon processors and 2 gigs of RAM. It also has the Nvidia Quadro4 980XGL card.

We're testing a rendered walk-around of one of our models. We ran a 50 frame segment successfully and got great results compared to our standard P4 station. However, when we tried to run a 150 frame segment, we found that 16 hours later, when it should have been done, it was only half way through and a "running low on memory while rendering" Revit error had appeared. I also noted that the elapsed time in the Revit status bar said only about 6 hours.

We have tried rebooting prior to starting the rendering session to make sure everything is cleared. No other programs are running during this time. We are connected to a network and it is possible that background programs may make demands on the station.

One of our IT staff looked at the record of the system's memory usage and it looks OK. He wonders if Revit is not properly "releasing memory". We have noticed that when the error occurs and you drag the warning dialog around the screen it leaves a video trail, suggesting that the problem is with graphics memory.

I should note that we also have gotten this error on our P4 stations - that's one of the reasons we wanted to try a more powerful box. But if this is a Revit or Accurender bug that happens even on an Intellistation Z-Pro, I can't see spending a large amount of money just to continue getting errors. If we need a rendering or walk-around for a meeting, I don't want to come in the next morning only to see its not done due to this error.

Any help would be appreciated.

P Ashley

[fernando]

it happens to me a lot of times tonow i use to render 50 frames a time
and in the end glue them all

[PeterJ]

If you have multiple Revit installations can you set up short walkthroughs as Fernando's suggestion and run them in parallel from a workset based file and then save and stitch back together? It's still only a workaround though.

[pashley]

Pete and Fernando,

That's what we've had to do - set up multiple stations running around 50 frames each. Unfortunately we don't have the technology to stitch the resulting files together, relyng instead on a local service to do that. What software would you recommend to stitch the multiple AVIs?

Regardless of the above solution, I would like to know if the folks at Revit recognise this problem. From a similar post on the Autodesk site, I gather that they either haven't seen the problem before or don't know what is causing it. I don't want to spend $7000 on a "rendering" station only to find I still have to create a mini "render farm" with my regular stations.

Another question - when you've seen this problem is it only with walk-throughs or with still renderings, too?

[PeterJ]

I use Adobe Premiere for video editing at home, Chris Zoog favours Sony's Vegas (I think) which does look good. Both are inexpensive but overkill for just stitching short runs together. More for use in post processing the whole thing.

Someone here has also mentioned www.radgametools.com (or something similar) for their Bink product, a free video tool which can stitch short runs together I think.

[sjsl]

We experienced that problem in the last build of Revit. We could not get a rendered walk-around to work and settled for a shaded view.

We are running P4's w/dual zeons. My rendering times for large exterior shots are in the low minutes.

I just recently did an exterior rendered walk-around without trees, just the building. I ran 1200 frames in about 5 hrs at medium setting. I kept the overall image size around 900x 600 pixels. The final output was 95 megs.

The new build of Revit is definitely a must if you are trying to do this!

[pashley]

Do you mean another build of 6.1? We are running 6.1 Build 20040306_0300. Is there a later one?

1200 frames in 5 hours? that's phenomenal. We have dual Xeons and they did 50 in 5 hours, which is still faster than our regular P4s.

What codec are you using for compression?

[fernando]

i use the last build of revit

and i don't render to AVI. i prefer to render to still images than use adobe premiere to join all, it give me the ability to change the frame rate at my use, and to clean any bad frame, and render a new one, if needed. join sound track, and get transition efects betwen animation and still images


usually this error only get with walktrghout , because in a simple image there was not a cumulative use of memory, as it is in a film

[fernando]

by the way, in my last animation i get frames rendering in 640x480 in 5minuts and another ones 10 or 20, of the same walktr
and the interior ones with lights and so on......30...50 minutes

[sjsl]

I am using build 2004 0616 2100. Are you from another country by chance?