[lustre-discuss] OSTs per OSS with ZFS

[Brian Andrus]

All,

We have been having some discussion about the best practices when 
creating OSTs with ZFS.

The basic question is: What is the best ration of OSTs per OSS when 
using ZFS?
It is easy enough to do a single OST with all disks and have reliable 
data protection provided by ZFS. It may be an better scenario when 
snapshots of lfs become a feature as well.

However, multiple OSTs can mean more stripes and faster reads/writes. I 
have seen some tests that were done quite some time ago which may not be 
so valid anymore with the updates to Lustre.

We have a system for testing that has 5 NVMes each. We can do 1 zfs file 
system with all or we can separate them into 5 (which would forgo some 
of the features of zfs).

Any prior experience/knowledge/suggestions would be appreciated.

Brian Andrus