3Par has introduced greater granularity into storage arrays by launching what it calls its adaptive optimisation software. The company is catching up with EMC which launched its own fully automated storage tiering last December 

Adaptive optimisation takes place at the sub-volume level, users with SSDs in their disk arrays will require fewer to meet their performance targets By using the technology they will be able to combining multiple storage tiers within a single volume for a lower overall cost per gigabyte than Fibre Channel-only configurations.

According to Craig Nunes, 3Par's VP of marketing, the technology will mean considerable cost saving for its customers, by being able to move from Fibre Channel to SATA. "We could be talking about 25 to 30 percent cost savings."

The nomenclature that 3Par uses to describe the layers in adaptive optimisation is regions. Nunes said that the technology works by establishing sub-volume data into areas called regions. "We watch those regions and monitor the performance. For example, when I/O increases we can move data up, when I/O goes down, we can move it down - there are something like 4000 regions, each of 500GB."

One of the key elements driven by this level of granularity will be the capacity to fine tune storage performance to meet SLAs. "We'll be introducing Quality of service gradient," said Nunes. "You can think of this as a sort of three-channel knob. This will have the capability to set the performance gradient, cost gradient, balance gradient, according to the wishes of the administrator. So if you have a particular SLA, you may want to err on the side of performance; if it's cost that's important, you don't want to move away from SATA and will adjust accordingly."