benchmarking NAS RAID rebuild times

[Tarrant1701]

Tim,

I enjoy reading your NAS reviews, but was hoping you could comment on RAID rebuild times. QNAP seems to be moving away from Intel Core processors and instead outfitting their SMB/SOHO/home lines with Atom processors. Since I doubt QNAP uses a dedicated RAID controller, that means all parity calculations are done on processor, and usually Atom processors have less compute power than their Core counterparts.

Do you think the choice of an Atom processor affects NAS performance at all? Certainly their RAID5 file read/write performances are solid, but what about RAID rebuild times?

Thanks!

 

[thiggins]

I have been noting rebuild times, but have been forgetting to include them in reviews.

I've noticed a trend where rebuild times are actually getting shorter. I believe this is because vendors are changing the rebuild defaults to skip the bad block check. Here are a few examples:

Thecus N4200PRO: "Quick RAID" rebuild time for 4 X 160 GB RAID 5 and 10 arrays, under 2 minutes!

QNAP TS-1079 Pro: 4 x 1 TB RAID 5. 2 hr, 30 mins

Before these lower numbers, RAID 5/10 rebuild of a 4 x 1 TB RAID with no other activity would take 8-10 hours.