- DNS response time and reachability are also very important factors when dealing with AD domain resolution. Any DNS or AD related issues will amplify any performance problem.
- Native Microsoft SMB servers may outperform SoftNAS in some cases if the attached Microsoft clients are taking advantage of the direct memory access and multi-channel capabilities not available in the open-sourced SAMBA service on our appliance. Also the SAMBA daemon runs in 'user space' on our appliance which is inherent of performance and resource restrictions.
- Just like NFS, some tuning can be done on both the SMB client as well as server side to attempt to increase performance. Tweaks to sockets, opportunistic locking, TCP options, and the send and recv buffers. None of this is recommended by the SAMBA organization but these are all options in smb.conf
- Refer to this external blog post for a good read regarding the context of changing specific parameters:
- Refer to this blog post from Samba telling us not to mess with these thingsthose same parameters:
"The Samba team highly-recommends not setting the parameters described in this section without understanding the technical background and knowing the consequences.
In most environments, setting these parameters or changing the defaults decreases the Samba network performance."
- Keep pool free space above 10% to avoid many metaslabs from reaching the 5% free space threshold to switch from first-fit to best-fit allocation strategies.
- The command 'zdb -mmm $YourPoolName' will show this information (see below)