I wish I could report that one of the big guys stepped up . . .
Instead, Jon Bach of Puget Custom Computers in suburban Seattle offered his company’s data on his blog post titled Why RAID is (usually) a Terrible Idea. It is a good post and well worth reading in its entirety
I liked it so much that I blogged about it on my ZDnet blog yesterday. Here I’m focusing on the drive numbers.
What are these numbers?
PCC sells hundreds of desktop systems per month and they track all failures and trouble tickets. Jon’s numbers include ALL drive failures, including those caused by mishandling, like when a WD Raptor got dropped on the warehouse floor.
Here is the data I have for our hard drive sales in the last year, where we have sold at least 200 units:
|Hard Drive Model||# of Units||Failure %|
|Seagate Barracuda 7200.9 250GB SATAII||280||3.21%|
|Seagate SATA Barracuda 80GB||271||2.58%|
|Western Digital SATA Raptor 74GB||592||2.03%|
|Seagate Barracuda 7200.10 320GB SATAII||202||1.98%|
|Seagate Barracuda 7200.9 160GB SATAII||265||1.89%|
|Seagate Barracuda 7200.9 80GB SATAII||403||1.74%|
|Western Digital ATA100 80.0GB WD800JB||290||1.72%|
|Western Digital SATA Raptor 150GB||278||1.44%|
|Total # of drives||2581||2.05%|
These are all first year numbers. And I think they show how reliable disk drives as a group are. Make no mistake: disk drives are probably the greatest IT bargain out there. Drive companies have done a great job making massive storage affordable.
I added the total
Maybe one of my statistically smarter readers can do more with these numbers. As I look at the numbers though, I see a mix of desktop and server drives with no particular pattern – a result that agrees with Bianca Shroeder’s paper from FAST ’07. Any other conclusions readers can reach?
Let us all know in the comments.
The StorageMojo take
It isn’t clear to me why folks who have the data about drive model reliability don’t want to publish it. Maybe they don’t want the hassle of customers requesting specific drives. Maybe all the drive and array makers do back room deals where they take volumes of not-as-good drives for knock-down prices and shovel them off to less-favored customers. Who knows?
Perhaps StorageMojo readers who have businesses like Jon’s or who work in corporate IT with access to failure data could pass it on to me. I’ll total them up and publish them. If a vendor doesn’t like the numbers then they can send me their own.
From a statistical perspective that’s a little rough, but we have to start somewhere.
Comments, as always, welcome. Moderation turned on to keep spam at bay.