“Each approach has its own attractions and dis-benefits, with those relating to the connection type being no different from those of conventional storage. The key attractions of SSDs from a datacentre perspective are of course performance, power and space.
Performance is probably the key issue though. For a virtualised environment, which majors in random rather than sequential access requests, getting enough IOPS from spinning disks is a struggle.”
Dubash then counters with this argument for high-speed hard disks:
“So why would still buy fast spinning storage? It’s still a lot cheaper per GB of course and SSDs do still, I feel, need to fully prove themselves in real world usage. And if you buy into SSDs, you still need a good answer when the CFO comes round and asks why so much is being spent on so little storage capacity, especially given that technology’s well-known propensity to wear out in relatively short order.”
There’s the challenge for SSD, SSD controller, and Flash memory designers. Bring SSD reliability up to snuff and high-speed hard disks are out the door. People will surely pay for performance, but not generally at the expense of reliability.
How will we get there? More ECC? Better ECC in the SSD controller? ECC on each Flash chip as just announced by Toshiba? (See “Toshiba adds 4 and 8Gbit BENAND devices to its SmartNAND lineup”) A replacement for Flash memory? Perhaps MRAM? Perhaps something else?
The economic rewards are high enough to ensure that many of these approaches will be attempted.
As for performance, here’s an Intel video from this week’s Storage Visions conference in Las Vegas that demonstrates the kind of performance gains we’re talking about. It shows an Intel Cherryville SSD versus a 10K RPM hard drive. Guess which drive wins?
This video shows what happens when you combine an SSD with the 6Gbps SATA 3.0 interface. Watch out hard drives!