Data density is great and all, but this line got me wondering if we wouldn't be supporting more than just the 2.5" and 3.5" form factors. I'm suspect there would be a market for storage devices with twice the volume and 50% or more storage. Or does the 3.5" form factor have something to do with the limitations of spinning rust tech?
There are issues. As the platters get bigger they get wobbly, more probe to vibrations. The difference in platter speed between the inner and outer 'rings' of data also increases. There is no hard reason for 3.5 over 4.5 or 4.8 inches, but the advantages of going bigger do not outweigh the practicalities of trying to push a new form factor for a commodity product.
>> spinning rust
This is a common refrain, but seagate and the others are proving that HDD tech is not 'rusting'. With lower per-TB costs, and phenomenal reliability numbers (<1% chance of failure per year) HDDs are going to be around for a while. Outside of the datacenter, most users are more limited by more by network speeds than storage speeds.
> This is a common refrain, but seagate and the others are proving that HDD tech is not 'rusting'.
It is a common refrain because disk platters were originally coated with iron oxide, and iron oxide is rust. It isn't a value judgement.
I think the original comparison to 'spinning rust' was tongue-in-cheek and not meant to be taken so-very-seriously, but it's kind of taken on a life of its own and, personally, I feel that it's gone a bit far and undeservedly undervalues hard drives.
"Logically, if you utilize a 'memory' disk you are ridding yourself of the physical limitations of disk drive technology — basically trading in the spinning rust. In a disk drive, you are battling physics to squeeze more performance out of your array; there are certain physical properties that just can’t be altered on a whim." - 2004
https://web.archive.org/web/20041018152106/http://www.dba-or...
As to the question of its present use as a method to hurt the feelings of hard drives and hard drive cognoscenti... I dunno.
I think you're reading too much into it.
- more power usage
- more heat
- more noise
Datacenters in particular are not interested in increasing heat or power usage. 5.25" hard drives used to be common, but were phased out sometime around Y2K.
There used to be larger form factors for HDs, for instance full-height 5.25 inch (think two DVD drives stacked on top of each other). This Wikipedia page has pictures: https://en.wikipedia.org/wiki/List_of_disk_drive_form_factor...
This was apparently a product that took the strategy you described in the 90s: https://en.wikipedia.org/wiki/Quantum_Bigfoot
There was a variant of the WD Raptor that took the opposite approach: it put a 2.5" 10k RPM drive in a 3.5" enclosure, but this drive played the role SSDs do today; they weren't for mass storage.
More the opposite, really - same capacity in lower volume. The people who buy most disks are a lot less concerned with capacity per disk than capacity per rack. Sometimes capacity per kW or capacity per BTU, but mostly capacity per m^3 in my direct experience. I also suspect that a lot of consumers would prefer the same capacity in a smaller package, since they mostly boot off flash and their disk is basically a cache for much larger amounts of data elsewhere.
With your extreme example, I doubt it. Already you can get two drives of 75% of the capacity for just a bit more money, and that would perform far better than one drive of twice the volume.
The current form factors are baked in, how would we know what the free variables are?