NetApp is adding solid state drives (SSD) and 2.5-inch disk drives to its FAS arrays to speed data access and increase power efficiency, but is not providing automated data movement - yet.
The company has a 4U DS4243 enclosure holding 24 3.5-inch 7,200rpm, 2TB SATA disk drives, or 15,000rpm SAS or 100GB SSD drives, with 300, 550 or 600GB capacity. Alternatively it can contain 100GB, single-level cell flash drives, source unknown, with a 6Gbit/s SAS interface. It could be STEC, which is used by EMC, IBM and HP/3PAR.
Flash and tiered data movement
Customers manually load volumes into the SSD storage, moving the volumes with Data Motion technology so that data access is not disrupted during the move. Unlike the similar drive shelf SSD offerings from Compellent, EMC, HDS, HP, IBM and others there is no automated data movement between storage tiers in FAS arrays.
NetApp's John Rollason, its EMEA solutions marketing manager, said: "In many ways, automated tiering is EMC and others' solution to a problem they created for themselves, and [the companies] are now telling the market everyone else needs it. We allow customers to store data on cheap and deep SATA drives and then accelerate the data that needs to be accessed quickly with Flash Cache across Unified Storage. We don't have the problem EMC needed to solve."
This is a view that should excite a lot of comment from NetApp's competitors.
Rollason also said that scripting can be used to semi-automate this process. He added: "I can say you can expect to hear more from us in the coming months as we continue to build on the core strengths of our portfolio to help customers meet their real objectives – to enable IT to be more flexible and efficient."
EMEA head Andreas Konig says NetApp hopes to automate up to 98 per cent of a FAS arrays operations eventually.
The hints are strong that Data Motion is going to get automated and, hopefully, there will be sub-volume level movement to provide more efficient control of hot data placement, as NetApp's competitors do.
Rollason said: "Flash Cache provides performance that is comparable to that of solid state disks (SSDs) without the complexity of another storage tier. With this approach, customers do not need to move data from tier to tier to optimise performance and cost. Active data automatically flows into Flash Cache because every volume and LUN behind the storage controller is subject to caching."
To guide customers choosing between controller-based Flash Cache or drive shelf SSDs NetApp says use SSDs to achieve consistently low latency with persistent storage, as is often needed for mission-critical databases. Flash Cache is an alternative to SSDs for workloads that are random read-intensive and high-access, or when “hot” data is less predictable, such as for server and desktop virtualisation, email, files shares and home directories.
Small form factor drives
The smaller DS2246 shelf is 2U high and holds up to 24 2.5-inch SAS drives spinning at 10,000rpm and with 450GB or 600GB capacities. NetApp says that, compared to a 4U DS4243 disk shelf with SAS drives of the same capacity, the DS2246 doubles the storage density, can increase performance density by 60 per cent, and can reduce power consumption by 30 to 50 per cent.
There has been a recent general adoption of small form factor drives. NetApp joins HDS and HP, who are using 2.5-inch drive arrays in the VSP/P9500 array as well as IBM, which is doing the same in its Storwize V7000.
NetApp can offer 10K rpm SAS drives for power-efficient I/O speed and Flash Cache front-end them for boosted speed; or they can offer 15K SAS drives for faster access to data on fewer drives, and Flash Cache turbo-charge them; or they can provide SSDs for workloads that demand low latency and don't suit the random-read focus of Flash Cache. ®