I'm using HDA-asset in Unreal Engine to create some set of unreal splines on its output. While it takes about 30 seconds in houdini to calculate all geometry, Unreal Engine freezes every time I try to calculate all geometry inside it.
Even if I open Houdini Session Sync I can see that my geometry is already calculated in houidini but at the same time Unreal Engine still calculates it.
Something defenitely going wrong with data transfer between houdini and Unreal. What could it be?

P.S. Houdini 19.0.498, Unreal Engine 5 Early Access 2, Houdini Engine 2.0.7 from github.
AMD Threadripper 3970x, RAM 96GB, GeForce 3980 TI.

i'm having the same issue, i wonder if there is any way around this?

Any more details you could give us ? an hda ?

Have you tried with a recent version of the plugin ?
I fixed an endless cook loop bug a while ago... so it's a possible that issue's already fixed.

Maybe related or not. I have a similar issue (but no curve) and I think it's related to the new refine static mesh. I've submitted a bug about refine not working with sublevel that is a huge problem and create bugs. Sometimes the refine is asked even if the mesh doesn't seems to need to be refine (bake button instead of Refine) and when doing a play from here a window "Refining Houdini proxy meshes to static meshes" appear and just do nothing at 0%. I have to manually do "Refine all Houdini Proxy Meshes to Static meshes" to find the one that needs it.

forgot to mention that I'm on 19.5.368

@PDGGoupil Yes, I'm currently taking a look at those refine issues, I assume you're on UE5 ?
Seems like the issue stems from changes made by Epic in UE5 (and unrelated to World partition)...
but basically, Houdini Asset components do not return their world anymore, which prevents the refinement from happening (since we do check their world matches the current).

Expect a fix for this soon.

dpernuit
Any more details you could give us ? an hda ?

Have you tried with a recent version of the plugin ?
I fixed an endless cook loop bug a while ago... so it's a possible that issue's already fixed.

Also maybe related or not and seems like I got a similar issue.

I have a highly integrated HDA with around 50+ sub-HDA files nested in it. Their path were written on .env file as HOUDINI_OTLSCAN_PATH. In Houdini it takes 1'50'' to calculate, yet its about 5-7 mins in Unreal.

Checking with Houdini Session Sync opened, what specifically happens is:

1. After I drag-and-drop to run the HDA in Unreal, Houdini immediately starts a kind of 'pre-calculation', BEFORE the HDA node's appearance on the Network View. The bottom log bar of Houdini shows 'cooking op...'; In Unreal nothing happens. This stage ran for about 2 mins
   
2. After the calculation is complete, the HDA node appears on the network. Then Houdini and Unreal both freeze, for 3-4 mins. CPU usage drops and stays <10%, GPU has no visible activity. RAM usage have a noticeable gradual rise during these few minutes. dont know whats happening in the backend
   
3. Unreal and Houdini recover from freeze, then Houdini starts the 'real' calculation with the bottom bar showing 'cooking op...'. If Session Sync was not opened at the beginning, after about 5 mins of Unreal being unresponsive, Houdini calculation logs are now finally started to display in the lower right corner of Unreal.
   

After all of the above, the geometry appears in Unreal, with twice repeated calculation and an unknown freeze in between.

Then I tried another test. In the same hda I only output a box with no dependencies but keep all the other nodes. In Unreal it still need to freeze for a few minutes to show that simple box.

I only have the experience of using some lightweight HDAs in Unreal before. so don't know if this is just normal or just a problem of myself.
I'm on Houdini 19.5.416 + Unreal 5.0.3; AMD 5950x, RAM 64GB, GeForce 3090 TI.