[nmglug] raid 10 vs 5

[Brendan]

On 09/09/2009 10:31 PM, Gary Sandine wrote:
> I never looked into this -- is it possible
> that hard drive manufacturers really have distinct manufacturing
> processes for their enterprise or server class disks and for their
> consumer class disks?  I'm not sure what the difference really is,
> but the failure rates reported by Google and what I have seen in
> practice (using consumer class disks in several 16 disk RAID arrays
> for a few years) are pretty low.

The enterprise drives typically have higher tolerances for things like 
cycle count, vibration, etc that they experience when they're packed in 
together in large arrays.  Since Google is doing 2 disks per server 
vibration may not be an issue for them.  Other suggestions:

1. Buy a drive with a 5 year warranty.  You will use it, even with 
enterprise grade drives.  Failure is inevitable.

2. Buy different models/mfr drives with the same specs.  It'll eliminate 
the chance of a bad batch of disks or bad model failing all at the same 
time.

-Brendan