Setting properties at load time

I’ve noticed that setting multiple properties (on an RVFormat node, for example) during a source-group-complete callback slows down our load time significantly. For example, loading 380 movies takes ~12 secs without setting the properties vs ~22 secs with setting them. I’m trying to figure out some alternative way of setting up viewport sizes that is faster at load time.

I noticed the OCIO plugin seems to be doing even more work during that source-group-complete callback, and still doesn’t seem to have any significant effect on load time. Is there something different about setting properties on an RVFormat node during load time that might start a big string of other events, that OCIO set up wouldn’t trigger?

Is there a better place to setup the viewport size/shape on sourcegroups, such as the first time source gets drawn? I don’t think there’s an event specifically for that, but I could probably hack something together for that purpose with the frame-changed event, and checking if the current source has the viewport properties we’re interested in.

This seems like something that would be common for studios to have to build – thanks for any ideas!
Alan