Cleversafe attempts to infiltrate the storage laws of power
Cunning object storage doesn't RAID the electricity budget
Cleversafe founder and vice chairman Chris Gladwin says his company's software is much more power-efficient than other scale-out disk drive array software or all-flash arrays. Object erasure coding can stop RAID crippling the power budget.
The object storage software Cleversafe sells uses erasure coding for data protection and not RAID. The company says it is much less wasteful of disk capacity than RAID and has paid for a Forester study that showed how a customer with a 15PB RAID array had 6PB of data with RAID copy data making up the other 9PB.
Once the customer had adopted Cleversafe's storage, it needed 7.2PB of storage capacity overall, with similar data protection capability, saving 7.8PB over the RAIDed system.
The metric Gladwin uses is watts per usable TB and these are the numbers he provides:
- Cleversafe with 4TB 5,400rpm disks – 3.3 W/usable TB
- Isilon – 13.3 W/usable TB
- Pure Storage all-flash array – 44 W/usable TB
Gladwin says that with 6TB and 8TB drives Cleversafe's watts/usable TB number will drop below 2. The more petabytes of data you have, the more important this measure is. Of course, it would be good to know the overall watts/TB figure as well.
It's fascinating and unexpected to see the high all-flash array number, as it is so much higher than Cleversafe's. Gladwin says that fetching large objects from disk is fast too, because the head/track latency delay is proportionately much lower than with small object IO.
You wouldn't use an all-flash array for scale-out object storage, of course, it being far, far too expensive for that. But who knows if in the SanDisk future lies cold all-flash archive stores, using 3D TLC flash?
Gladwin told us that spin-down drives don't improve the watt/TB number, because spinning the drives up requires a lot of power relative to the steady spinning state. Also, spin-down drives gave slower data access than spinning drives.
Power budgets for petabyte-class arrays become more and more important as power becomes more expensive. Cleversafe has several 100PB-plus customers and one who is heading towards 1,000PB – an exabyte. Calculate the watts/usable TB for that, the equivalent of 3,300,000 W (3.3 MW), and power costs become hugely important. ®