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Google Proposes New Hard Drive Format For Data Centers (thestack.com)
An anonymous reader writes: In a new research paper the VP of Infrastructure at Google argues for hard drive manufacturers and data center provisioners to consider revisions to the current 3.5" form-factor in favour of taller, multi-platter form factors — with the possibility of combining the new format with HDDs of smaller circumference which hold less data but have better seek times. Eric Brewer, also a professor at UC Berkeley, writes "The current 3.5" HDD geometry was adopted for historic reasons – its size inherited from the PC floppy disk. An alternative form factor should yield a better TCO overall. Changing the form factor is a long term process that requires a broad discussion, but we believe it should be considered."
The world will probably keep using spinning rust until purchase price (not TCO) on SSDs is lower. I wouldn't be surprised if makers went back to 5.25 x half height, and low spindle speeds. It would still permit large throughput with high density, but seeks would be slower. Not a big deal with enough caching in front of them, and/or with enough disks in an array. As SSDs approach HDD price, they will take up more of the workloads that actually have to be fast anyway.
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
I just wonder if, by the time they agree on this (if they do) the price of SSDs will have dropped enough so that they can be used instead? Storage-wise they are already there, and then some.
The point is to keep spinning platters cost-competitive with SSDs - a taller, smaller form factor would increase performance and reduce TCO... I'm thinking they're looking at something like lots of 1.8" platters stacked 4" high, they can spin faster, have faster seek times, and package multiple TB per unit, and I think the longer single bearing should be a more favorable geometry than the ultra-thin notebook compatible drives that have been developed for the last 10 years. It will be slower than SSD, but the power performance (which is the key to TCO) should remain competitive with SSDs for a long time to come. Also, presumably, if this takes off it would be datacenter focused, so longevity (again, TCO focus) should also be "baked into" the design in favor of lower retail price.
Multiple heads on each side of the platter might be a better solution, one for the inner part and one for the outer.
Wait, what? Last time I opened up a dead 3.5" hard drive (which was only a few years ago) it had either three or four platters. Are you saying they typically only have one now?
But yes, I agree that if they want taller drives, 5 1/4" full height would be a good form factor. Maybe even not with 5" platters! If they want quicker speeds, they could maybe put four separate spindles of the platters from 2.5" drives inside the same box.
"[Regarding the 'cloud,'] ownership was what made America different than Russia." -- Woz
It sounds like you think that manufacturers have stopped making multi-platter drives. That's not true. Seagate and WD both use seven platters in their highest-capacity (10TB, standard-height) drives. The linked article further states that they use seven platters "instead of the usual six".
I don't know how prevalent single-platter drives are today, but multi-platter drives certainly haven't disappeared.
The power performance will NEVER COME CLOSE to being as low as an SSD.
Even my first-gen SSDs use far less power than a regular laptop drive. Taller drive geometry = more power to spin the spindle. You do know what an ?INDUCTIVE LOAD is, right? If not, protip for you: The amount of power you use to spin up those platters alone is all the power I need to find and transfer data from my SSD. And that's done before your drive heads even begin moving!
Still waiting on Serviscope_minor to wake up to fucking reality and realize that Jessica Price isn't going to fuck him.
I'm surprised that they haven't just done away with the 'hard drive' as is. SSDs are just a bunch of chips. I'm thinking of a 1U server that is just a board populated with chips, a fiber interface and a powersupply. Treat the 1U server as a single unit.
When you start to add up hard drive casing, interface connectors, etc you end up wasting a lot of space for no reason. For the home user that only has 1-2 drives they make sense but for someone like Google that may have thousands of drives just jump up to the next standard unit and make that the 'storage device'.
Old SSDs died quickly under DB loads - not enough write count in their lifetime. New ones are better, but still won't last as long as HDD.
Let's take a decent 15k, even ignoring seek times the rotational latency limits us to about 500 IOPS.
Saturating that with 4k writes 24/7 for a year... about 63.12 TB written.
What's the write rating on a 200GB intel DC P3700? 3737.6TB.
Do you honestly expect that HD to survive for nearly 60 years?
You could very well be right. Speaking of oddball heights, the first 500 *MB* drive I bought (back when the main network drive was 120MB) cost $1000, and it was actually a 3 1/2" double-height size, meaning the bay next to it had to be clear before I could install it. It wasn't a problem since I was simply installing it in a workstation. This obviously wouldn't work for Google, since I'm certain they use computers with front-mounted hot-swappable 3 1/2" drive bays all neatly packed together - I've seen how nicely these work with my Synology 5-bay NAS. Unless a new form factor becomes standardized, you can't really hack in a solution... at least not on the scale Google is dealing with.
I don't think Google is going to get its way here with a new standardized size, at least at mass adoption scales. Inertia is pretty damn hard to overcome, even if potentially superior solutions exist. I mean, the US is still using imperial measurements, for heaven's sake. The fact that we measure them as 3 1/2" inch drives should tell you something about how hard it is to change standards.
Irony: Agile development has too much intertia to be abandoned now.