[TriLUG] SSD-based NFS servers for production - ready for primetime?

[Jeff Schornick]

Have you considered rethinking your RAID layout?

I'm no storage expert, but red flags start to pop up when I read this
combination of statements:

> has pushed the NFS servers to the point of I/O starvation.
> As for the configuration, I will put them in a 6-drive RAID-5 array using Linux software RAID.
> we need about 1.5T of usable NFS space to store VMDKs and other high-sensitive items.

What does your I/O profile look like?

Given the sensitivity of the data, I/O starvation, and relatively
small storage requirement, I would strongly consider a RAID10 profile.
 It's more straightforward, more resilient, performs better in a
write-heavy environment, and should be tunable to perform just a s
well as RAID5 on reads.

There are fancier things out there, but when limiting the choices to
software raid, you have to work pretty hard to steer me away from
RAID10.

Coming from another direction, given the low price of memory these
days, would your NFS servers benefit from spending the money on more
memory?  Once again, depending on your I/O profile, more caching could
be a cheap and effective upgrade.

Yet another area to consider... how many NFS servers are we talking,
and how is the data distributed?

  - Jeff