Upgrade from 9.x to 10.1.0.2 slows down CIFS/SMB

[DatatoSecure]

Hello,

We recently upgraded from 9.x to 10.1.0.2, performance is very slow (performance was fine before upgrade).
We send traffic from Windows Servers 2008 & 2012.
CIFS/SMB:
Max Protocol SMB3
Send Buffer Size 128480 (default value)
Receive Buffer Size 128480 (default value)
Large read/write enabled
Asynchronous I/O (AIO) does not seem to help either way.

System:
NAS4Free 10.1.0.2 (revision 1731) x64-embedded;
INTEL S2600CP Xeon CPU E5-2609 v2 @ 2.50GHz 32 GB RAM
ZFS Pool raidz2, NO deduplication, encryption or compression.


How can we fix this?
Regards.

[raulfg3]

please try:

Max Protocol SMB2

and

Send Buffer Size 64240
Receive Buffer Size 64240

this changes works fine for me.

[daoyama]

Try to disable Tuning @ System|Advanced.
Then, enable Tuning again.
Also check net.inet.tcp.delayed_ack @ System|Advanced|sysctl.conf. (try 0 or 1)