Do you know how to stop unnecessary reckooking of all Cache LOPs after using(pressing save/render/etc button) Rop nodes in Lop context?

Can I just check whether this is in Houdini 19.5 or an earlier version?

robp_sidefx
Can I just check whether this is in Houdini 19.5 or an earlier version?

Houdini 19.5
usd_rop1 → press Save to Disk = saved file but after saving, cache1 node begin reckook data

tachbek
Houdini 19.5

Thanks for confirming, and for the sample .hip file.

The issue you're seeing is a default setting combined with behaviour invoked by our USD ROPs. On the Cache LOP, the "Start/End/Inc" are being driven by @ropstart/@ropend/@ropinc and, when activated, the ROP sets these context options.

Let's take the example of saving the current frame to disk. When you click "Save to Disk", @ropstart and @ropend will get set to that frame number. Because these are driving the Cache LOP, the Cache LOP recooks just for the current frame, and then that data is saved to disk. After the ROP completes, @ropstart and @ropend get effectively reset to the timeline range, and the Cache LOP recooks again (for the full range).

If you change the Cache LOP's range to be driven by $RFSTART/$RFEND/1 (as was the case in Houdini 19.0), you should be able to avoid the recooking you've been seeing. For better or worse, you'll also get behaviour more similar to Houdini 19.0 in terms of the data generated. By this I mean that if the Cache LOP is driven by @ropbegin/@ropend and you tell the ROP to write data for frames 5-8, you'll only cache and write-to-disk time samples for frames 5-8 (when using "Always Cache All Frames" - as you are). If you use $RFSTART/$RFEND, you'll cache and write-to-disk time samples for the full 1-240 frame range.

I appreciate this is potentially confusing default behaviour, and is a change from Houdini 19.0. We're actively discussing this and how best to ensure the right balance for users getting performant and predictable workflows. It's helpful for us to hear these situations where we haven't gotten it quite right.

It worked, thank you!