Hi,
For the past week I've been trying to troubleshoot a problem I have with Mantra. It seems like Mantra is having issues with some certain frame numbers, such as frame 61 and sometime even certain range of frames(i.e. 110 to 121). I tried to rerender many times, both locally and with the renderfarm, still came to the same crashing results. I have a very simple camera in the scene and I've tried to reanimate the camera just to see what difference could it make. The result is the crashing frame number either move forward or backward. Rerender the same hip file will generate the same result like before. Can anyone shed some light at this problem? Thanks.
Regards,
D'Lun
Full Version: Mantra constantly crashing at certain frame numbers
That's really hard to say. It could be several things, the first two which come to my mind:
- Memory. If you look at the memory size of the mantra executable when rendering those crashing frames, check to see if it's really big (like 1.5 GB on Windows or around 2 GB on Linux).
- Bug in mantra. You could try downloading and installing the latest build to see if the problem has since been fixed.
A frequent suggestion is to systematically determine what in your scene is causing the problem. Find the frame where you consistently get crashing. Start removing objects one by one and rendering until it doesn't crash anymore. This is a slow process though if it takes long time before the crashing occurs while rendering.
- Memory. If you look at the memory size of the mantra executable when rendering those crashing frames, check to see if it's really big (like 1.5 GB on Windows or around 2 GB on Linux).
- Bug in mantra. You could try downloading and installing the latest build to see if the problem has since been fixed.
A frequent suggestion is to systematically determine what in your scene is causing the problem. Find the frame where you consistently get crashing. Start removing objects one by one and rendering until it doesn't crash anymore. This is a slow process though if it takes long time before the crashing occurs while rendering.
Thanks for the tips! I will go ahead and give it a try. 
Regards,
D'Lun
Regards,
D'Lun
I had same problems from time to time.
In most cases it was solved by increasing Bucket Size value (“mantra -B 128” or even 256)
In most cases it was solved by increasing Bucket Size value (“mantra -B 128” or even 256)
Couple of other tips.
When removing objects to find the culprit do it by halves. That is remove half of your objects from the scene and render, if it works the problem is with the other half, if it doesn't the problem is with the first half. Just keep repeating this process and you will quickly find the one causing the trouble.
Second sometimes rendering straight to mplay rather than disk will fix the problem, if not you might be able to tell from the bucket it falls over on which object is not working.
Thirdly, render pics, when mantra crashes you can still open a pic and see how much of the frame it generated.
When removing objects to find the culprit do it by halves. That is remove half of your objects from the scene and render, if it works the problem is with the other half, if it doesn't the problem is with the first half. Just keep repeating this process and you will quickly find the one causing the trouble.
Second sometimes rendering straight to mplay rather than disk will fix the problem, if not you might be able to tell from the bucket it falls over on which object is not working.
Thirdly, render pics, when mantra crashes you can still open a pic and see how much of the frame it generated.
Good tips; all
One more thing that can also help: some nastier crashes even occur depending on which buckets get rendered first. This happens when if you render to “ip” and it works, but crashes when rendering to disk. So to render to mplay and still emulate the bucket order in which mantra renders when writing to disk, use “md” instead of “ip”.
Good huntin'
J
One more thing that can also help: some nastier crashes even occur depending on which buckets get rendered first. This happens when if you render to “ip” and it works, but crashes when rendering to disk. So to render to mplay and still emulate the bucket order in which mantra renders when writing to disk, use “md” instead of “ip”.
Good huntin'
J
Thanks, all! I finally found where the problem is. As always, it all caused by the displacement objects. I guess Mantra just gave up up to some certain frames when it's doing the displacement. After I separeated them for rendering passes, it works like a charm. Thanks again everybody for the great tips and quick replies!
Regards,
D'Lun
Regards,
D'Lun