[CentOS] 40TB File System Recommendations

Wed Apr 13 13:50:46 UTC 2011
Lamar Owen <lowen at pari.edu>

On Tuesday, April 12, 2011 07:00:26 PM compdoc wrote:
> I've had good luck with green, 5400 rpm Samsung drives. They don't spin down
> automatically and work fine in my raid 5 arrays. The cost is about $80 for
> 2TB drives.

And that's a good price point for a commodity drive; not something I would count on for long-term use, but still a good price point.

> I also have a few 5900 rpm Seagate ST32000542AS drives, but not currently in
> raids. They don't spin down, so I'm sure they would be fine in a raid.

The biggest issue isn't the spindown.  Google 'WDTLER' and see the other, bigger, issue.  In a nutshell, TLER (Time-Limited Error Recovery; see https://secure.wikimedia.org/wikipedia/en/wiki/TLER ) allows the drive to not try to recover soft errors quite as long.  The error recovery time can cause the drive to drop out of RAID sets and be marked as faulted.

> Just because they are so tiny on the outside, 2.5 inch drives like the
> Seagate Constellation and WD Raptors are great. Unfortunately, the don't
> come any larger than 1TB, so I use them in special situations.

FWIW, EMC's new VNX storage systems are at the 2.5 inch formfactor, with SSD and mechanical platter drives as options, using 6G SAS interfaces.