Welcome to the forum @BestITGuys
Blog post: Cut restore times by 3.8x - A deep dive into our new restore flow
might describe cache you’re seeing, but it should run with either UI AFAIK. It did when I tried.
Restore fills up /tmp directory #6577 starts my thoughts on the new need for more /tmp (sigh).
tempdir option can move the location for it, or legacy-restore can get the old restore way.
There’s also a restore-volume-cache-hint cooking in Canary, but all this seems a bit hard.
I could be wrong about some of this, and it would be better to have some developer comment.
Possibly this is all off-target. Your comment about the old UI not having issue is puzzling to me.
One way to distinguish is that a live log at verbose level looks much different between methods.