Help Debugging Slow File Transfer via Finder to Drobo 5N

Hi - I’ve been trying to debug very slow transfer speeds of my backup solution to my Drobo 5N and have found some dramatic differences in transfer speed using Finder vs scp. I have narrowed the performance issue to transferring folders with a large number of small files (my test folder for benchmarking speed is 2,600 files with a total size of 11MB).

The issue appears to be specific to the OS X connection to the Drobo 5N; transferring the 2,600 files via scp takes 17 seconds, while transferring via Finder takes about 3 minutes. I’ve read various articles online about Finder performance issues and connecting with afp vs smb, but there does not appear to be a performance difference when using Finder between afp and smb. I’ve also tried using several Finder alternatives like Commander One, etc, but they do not show better performance. In short, I can only get decent transfer speeds using scp but not through the OS X network connection.

How can I go about debugging this performance issue further? I recognize that the issue may not be specific to Drobo (or it may, I’m not sure how to test further to know for sure). Can anyone provide some pointers to known performance issues with OS X connections to Drobo 5N and/or steps for debugging further?

I’m using:

OS X 10.15.7 (Catalina)
Drobo Firmware 4.1.4-8.120.108863


No takers? Does anyone have a suggestion for somewhere else I can post to get some debugging help?

Apple would be who to ask, they have forums too, as a mostly Windows & sometimes Linux user, I wish I could help, all I can say is transferring many small files involves a lot of lookups to find the locations & extents thereof, how Finder & SCP handle that probably differs.

You should see the difference in Windows between using explorer & the command prompt & xcopy… the latter isn’t funny.

Thanks, I’ll try posting elsewhere and post back here if I learn anything that could be useful to others.