Hello!

I'm currently creating an ocean simulation for a personal project I am doing and am having real trouble rendering it out. I am currently on day 4 of the render when it should have only taken 3 and I am barely half way through my frame range. In my test renders a frame took about 17 minutes to render, this was reflected in the first 68 frames that were rendered out which all took about the same time. Since then however my render speed has slowed and slowed, every time I restart the render the first few frames take about 17 minutes again, and then it slows right down to over an hour per frame. On the first day on frame 69 the program crashed but I don't know why and I don't know how to find out. Please help me. Happy to post any files required just tell me where to find them.

I would suggest rendering with verbosity level 2 or higher, which will give you detailed information regarding raycounts, memory usage, etc. then compare the stats between the two renders with large render time discrepancies and see if there are any obvious culprits. It might be also helpful to have some sort of system monitor running to see if cpu isn't being thermal throttled.

how is it being rendered?
locally from the hipfile, farmed mantra via ifds or farmed with hbatch?

cpb
how is it being rendered?
locally from the hipfile, farmed mantra via ifds or farmed with hbatch?

I'm rendering it locally on the same machine that's running Houdini so I think from the hipnc file??

dlee
I would suggest rendering with verbosity level 2 or higher, which will give you detailed information regarding raycounts, memory usage, etc. then compare the stats between the two renders with large render time discrepancies and see if there are any obvious culprits. It might be also helpful to have some sort of system monitor running to see if cpu isn't being thermal throttled.

I've turned on verbosity now, how do I view the statistics that it creates? I left it overnight again, this time it managed two frames and then just stopped for some reason.

Is there any way I can find why it keeps crashing in like error logs or something?

Update:

I've sat with the computer today while it renders and watched it. Today I'm using the Rend To Disk In Background option and looking at task manager it seems to be when Mantra starts actually rendering the frame after hbatch has actually generated it that Windows is freezing and taking around 20 minutes to recover from. At this point it looks like my memory is completely full. This doesn't really help me as I don't know how to fix that but does that mean anything to anyone else? Should I reduce the proportion of physical memory my mantra nodes are set to use, currently they are at 0.75.

You can write render logs to file by adding -o option to mantra command in your mantra ROP. (e.g. under driver->command tab, you can enter “mantra -o Ctemp/log$F.txt”) It sounds like it's threshing due to not having enough ram to handle both hbatch/houdini session and mantra at the same time though - in which case you may have better luck adopting different workflows, such writing out to ifds (you won't be able to do this as indie or apprentice user), or caching out geo to disk and import them in a new scene as packed disk primitive and keep hbatch/houdini session lightweight.

it smells like a memory leak.

try farming it to hbatch: it should open the hipfile, render it, then terminate - freeing your memory between frames.

cpb
it smells like a memory leak.

try farming it to hbatch: it should open the hipfile, render it, then terminate - freeing your memory between frames.

Unfortunately it doesn't look like it is terminating the memory even when I'm using hbatch after a couple frames the my physical memory is at 100% even though, according to TM there's nothing using more than a few hundred Mb of RAM, trying some 3rd party software now to combat memory leaks.

sorry forgot to mention farming it as 1-frame per task…

cpb
sorry forgot to mention farming it as 1-frame per task…

Thanks, I'm trying that now! How do I get it to render each frame consecutively? Currently when I queue multiple frames in hbatch it's trying to do them all at the same time.

SeanRalphs19
How do I get it to render each frame consecutively?

depends on what task scheduler you're using… if its Deadline try adding -chunksize 1 to the command.

cpb

SeanRalphs19
How do I get it to render each frame consecutively?

depends on what task scheduler you're using… if its Deadline try adding -chunksize 1 to the command.

At the moment I'm just using the built in Houdini one (when you click Render To Disk In Background and the popup asks whether to open the scheduler?)

ah yep that'll send it as one job…
If you have time try using Deadline, you can run it locally.
Otherwise I can set you up with a shell-script workaround if you're on Linux.