[Samba] Changing Windows permissions runs very slow

[Ken McDonald]

Is it normal for changing of Windows ACL permissions to run very slow? 
I've tried running perm changes across a lot of files (like 1TB) in user 
directories by interactive session from a domain-connected Windows 
desktop AND from the command line on the Samba server itself like this

find install -type f -exec samba-tool ntacl set 
"O:LAG:S-1-22-2-0D:AI(A;ID;0x001f01ff;;;S-1-5-21-1719490861-3494379899-4222726569-1105)(A;ID;0x001200a9;;;S-1-5-21-1719490861-3494379899-4222726569-1106)(A;ID;0x001200a9;;;DU)(A;ID;0x001f01ff;;;DA)" 
{} \;

While I feel like the command-line version is running faster, but 
methods seem to take a very long time, like days.

When I monitor the Samba server utilization while doing the interactive 
method, a sole smbd process runs at about 90-100%, which I suppose is 
expected because it's running across a share and I guess smbd is not 
going to run on multiple cores.

When I monitor the Samba server while doing the local command-line 
version, no process seems to be running at high utilization and the 
drives are barely lighting up. This is all on a Dell dual-cpu xeon 
server with 32gb ram and a bunch of raid drives. I realize the 
samba-tool command is being repeatedly executed as the find recurses, 
but I would have expected a much more lively server while this was running.

Seems like the perm changes take a really long time and I'm curious if 
something is wrong on my end. The Samba server is the sole server in the 
domain and also running DC role. I realize this is not the ideal 
configuration for the file server role.