I'm seeing "resource busy" errors from a system working with TrueNAS

I have had some minor issues lately which I do believe are probably my own fault and not a bug.

A docker container, running on a linux host, talking to TrueNAS over SMB is coming back with the error.

Unable to move file /TRUENAS/DOWNLOAD/BLAH-ABC123/FILENAME to TRUENAS/MEDIA/BLAH-ABC12/NEW-FILENAME : OSError(16, 'Resource busy')

I am unsure how to isolate if this fault is a busy pool, busy SMB service, if it’s a pool which one? Etc.
Is there some kind of log within TrueNAS which will help me identify a resource so busy it would report back with “resource busy” to another system?

Thanks anyone who can assist.

Please post your hardware details, pool details, TrueNAS version and wether or not you are using dedupe on your pool

64GB Denverton 8 core.
It’s either a 6x 2TB SATA SSD Patriot Burst Pool or a 6x16TB SATA Segate 3.5" 7200RPM pool.
No dedupe
No compression for the 2 pools in discussion
Core, latest