Looking for hardware advice

[RxScram]

Hi All,

I've spent a fair amount of time reading the noob guide, the FreeNAS documentation, etc., so hopefully I won't ask anything too stupid.

The build I am considering is essentially the following:

Intel i7 Quad Core processor (Probably i7-3615)
16GB RAM
2x dual port 10Gb Ethernet (4 ports total, Intel X540 based cards)
6x 500 GB SSDs (4 RAID-Z + 1 Parity + 1 Hot Spare). I may decide to go up to 8 SSDs total.
CF Boot drive (2 GB?)

RAID or PCH -> Part of the requirements for this is that the system must detect a failing/failed drive and automatically start the transfer process to the hot spare. The documentation says to use a RAID card with good monitoring capability to allow this. I believe the LSI MegaRAID 9271-8i (as JBOD, or RAID 0 with array sizes of 1) would allow that, but does anybody have any other suggestions?

The way that this NAS will be used is that it will be connected to 4 computers, each through its own 10Gb Ethernet port.

Does anybody have a gut feel for how it would perform? Is the CPU and RAM enough, or do I need something more powerful? I realize it's only using 5 SSDs, but I'd like to get as much performance as I can out of it.

Thanks!

 

[ben]

I doubt this will saturate all four 10GBE links, but if you just want to avoid being capped by 1GbE links that makes sense. Be sure to check "force 4K block size" when making the pool. Your current config is ideal for RAID-Z in terms of drive count (power of 2 data drives plus parity level), so think twice before going up to 8 drives. Automatic use of hotspare is questionable - I'm not sure FreeNAS currently supports that regardless of how good the disk monitoring is. As for CF boot - check your board's support for that. Most people have better results with USB drives or SATA or USB DOMs. Go with a 4GB boot device, to be sure you avoid the drive manufacturer lies.

 

[RxScram]

Yeah, I'm not so much interested in saturating all of the links as just not being bottlenecked. I think a reasonable goal is 500 MB/sec combined... seem doable?

Thanks for pointing out the drive count. Hmm, I'll have to investigate the hotspare more...

 

[cyberjock]

Just for comparison.. if it helps you at all with a datapoint. I have an 18 drive RAIDZ3 with WD Green 2TB drives with 4k sector size drives and 4k sector size zpool and I can do about 800MB/sec with dd command.

 

[RxScram]

Just for comparison.. if it helps you at all with a datapoint. I have an 18 drive RAIDZ3 with WD Green 2TB drives with 4k sector size drives and 4k sector size zpool and I can do about 800MB/sec with dd command.

Thanks! That does help. Can I ask what CPU, how much memory, and what your cpu utilization is?

 

[cyberjock]

Typical CPU utilization is <5%, 20GB of RAM, and the CPU is a first gen 2.0Ghz i7-xeon. I don't remember the exact model :(