Jetson nano 4GB starts booting very slowly about 20 minutes

It is possible. Which software release are you using now? Is it possible to move to r32.6.1?

We do have some changes to make the gpu driver loaded faster. Not sure if that can help your case or not.

I reflashed today with latest release. And error still persisted. But I launch my program with small time delay and all fine now. Thank you very much that you paid my attention to problems with gpu.