Hi

I have around 100 ships in the scene. Cached out cloth sims for them as separate USD files per ship, and referenced all of them in one master USD file.

Size of these individual USD cache files is around 140 gigs.
Size of master USD file is couple of kilobytes.

When loading that master USD file inside Light scene on 128 gig machine it loads and renders nicely.
On 64 gig machine it crashes. In both cases RAM doesn't go over 30gigs.

In the same light scene, if I load these cloth caches as bgeo sequences in SOP create node, it renders nicely both on 64 and 128gb machines.

It seems to me that Houdini tries to load not only current frame from these USD files, but all frames and it just fills out RAM on loading. It doesn't happen on 128gb machine since RAM + virtual memory on it is larger than size of all USD caches.

Also, I am testing on Windows 10, Houdini 19.0.531

In my experience, once cached on disk, Solaris loads around the current frame (plus-minus one frame) for motion blur purposes, but not all the animation. I might be wrong, but I see no reason for it to load "the whole thing".

Other notes, even though nobody asked
Make sure you're only writing the P (position) attribute to disk as an animation layer over the static cloth (no need for other attributes like topology, uvs, etc.) It saves a lot of space.
Not sure how your shots look, but for the distant ships I'd just reuse 3-4-5 caches with time offsets (if it's just the "default" sail in the wind).

Also, what render engine?

There was a USD bug where even though USD wouldn't load the whole 140GB from disk, it would insist that your machine have at least 140GB of virtual memory, and crash if you didn't. In 19.0.699, we incorporated a fix from Pixar for this issue, so my first suggestion would be to run your test with a newer version of Houdini.

mtucker
There was a USD bug where even though USD wouldn't load the whole 140GB from disk, it would insist that your machine have at least 140GB of virtual memory, and crash if you didn't. In 19.0.699, we incorporated a fix from Pixar for this issue, so my first suggestion would be to run your test with a newer version of Houdini.

Thanks a lot. Trying out newer build of 19.0 then