BUILD Planning a system for further expansion

[Urs]

Hi there,

having getting some experience with freenas with the backup-system i build (amd ecc error checking thread ;-) ), i now feel confident about using freenas for the replacement of my main system here.

It is serving 20 clients with data at the moment and is fucking slow.... Also there will be the domain server with roaming profiles running on it.

First thing i have planned is using a raid-z3 on 9 small disks, having 1 or 2 tb each, so later i can bigger the pool if necessary by switching the drives to 4 or 6 tb ones. (or stripe a second raid-z3 of 9 disks to it.)

About performance, i hope i am right with my assumption there, my first concern should be RAM, i think of going with 64GB in the beginning and a single cpu (opteron/xeon) with a nice double cpu supermicro board.
Thats because if my needs grow i can first populate the second rows of ram and after that a second cpu with the 3./4. rows of ram if needed.

How can you determine, or does somebody know, if sync writes are a concern? If i am using the freenas machine as a domain server with roaming profiles ist there a ZIL useful? (if so, i would mirror 3 small, fast enterprise ssds for that)

Before taking L2ARC into concern i would raise my memory...

Network will be intel 10GBit, so that shouldn´t be a bottleneck either.

thanks for any thoughts!

 

[L]

What kind of clients? ZIL is only viable for nfs. CIFS doesn't touch it. L2 is for read performance.

Having more vdev's is better than one big vdev. It also makes it easier to add. So 3 - raidz1 should perform better than 1 raidz3.

 

[Urs]

20 win 7 clients and
one server hosting virtual servers, but nearly no traffic of them, sharing done for them via cifs, running with virtualbox
ok, that cifs isn´t using sync writes at all is fine, so no ZIL devices!

 

[L]

So how horrible is the performance? What does your typical workload look like?

 

[Urs]

im working in an power-electronics lab, so r&d, but not that "heavy" ones like simulation large systems.
My vms are just running our internal wiki and svn and such things.
The problem at the moment is, that we are using an really old nas solution, soc-chip, not a x86 based one.