Sure, deal with Leia first, we can look at this once you got some time to spare. I leave the unit untouched and temporarily switch to NFS for the time being until there is time to revisit this issue and find some kind of root cause why SMB performance is so abyssal here.
As why the current settings are not exposed, a quick look at vero3-linux/fs/cifs/cifsfs.c at master · osmc/vero3-linux · GitHub shows:
module_param(CIFSMaxBufSize, uint, 0);
whereas since a couple of years it is:
`
module_param(CIFSMaxBufSize, uint, 0444);
Well given that it seems to be version 2.02, there are of course quite a few things missing.
Though still does not explain why I had way better performance before the update. In theory it could be possible that I tweaked something on the CIFS side on the Vero and simply forgot about it. I cannot rule this one out. Getting old…
Anyway, we can revisit this once you done with Leia. Maybe backporting a newer version of cifs.ko might be an option in general, as there were quite a few fixes?