When Spectra Logic launched its DPE archive-class NAS in September it was a play at a space often targeted now by object storage products. So, I asked whether Spectra Logic had considered object storage. It’s an obvious choice for large amounts of unstructured data.
The answer to the question came in October when Spectra Logic married its Black Pearl object storage head with a back end that can comprise a mixture of 8TB Shingled Magnetic Recording (SMR) drives (the ones that overlap data tracks to pack more in) that can be powered down with tape.
The idea is that Arctic Blue performs the role of an archive layer, but with tiers that allow for varying read and write times.
On the one hand the different classes of media – disk and tape – are better suited to reads and writes respectively, so Spectra Logic claims the same throughput (around 1GBps) for reads and writes. Normally, with just disk, reads would be much fast than writes but tape’s fast write speeds evens the two out.
Also, policies can be set so that stored data is stored and migrated to different tiers: Spinning SMR disk, powered-down SMR disk, and tape. Claimed access times are less than 1 millisecond for powered-up disk drives and about 30 seconds for powered down SMR drives.
Arctic Blue puts up to 96 8TB SMR HDDs in a 4U box. Four of these can be clustered to provide a full rack of 6.4PB of disk. To this can be added tape capacity up to exabytes in scale.
Spectra Logic says the cost of storage on Arctic Blue is around 10c per GB, which it says compares to 7c for a tape library. Its ideal user, it says, is a customer that is probably at less than 3PB of capacity and is happy to pay the extra 3c per GB for the features – ie tiering – that a pure tape library can’t offer.