The idea of hybrid drives is mostly a cheap knockoff for those who don't want to buy a true SSD of a decent capacity.
Hybrid hard disk drives have been on the market since Seagate Technology and Samsung Electronics introduced their versions in 2006 and 2007, respectively. The popularity of such drives has so far been pretty low and hard drive makers Toshiba Corp. and Western Digital Corp. only recently started to develop hybrid storage solutions. Nonetheless, manufacturers and analysts are optimistic about hybrid storage. Toshiba expects half of mobile hard drives to feature NAND flash cache in just two years of time.
At the Consumer Electronics Show (CES) last week Toshiba said that it had already started developing next generation hybrid drives and will continue to promote advances in its storage products business, pursuing development of solutions offering higher capacities and performance. The company also said that it expects hybrid drives to account for about half of all 2.5” storage products shipped for the notebook PC market in fiscal year 2015.
Toshiba’s first-generation hybrid hard drives provide 1TB (MQ01ABD100H) or 750GB (MQ01ABD075H) capacities as well as 8GB single-level cell (SLC) NAND flash memory as a cache memory to support high speed data throughput. The drives support rotational speed of up to 5400rpm, use Serial ATA-600 interface and come equipped with 32MB of DRAM cache. The new HHDs come in industry-standard 2.5"/9.5mm form-factor.
In operation, data is allocated to one of the hybrid drive's three memory layers: DRAM buffer memory, NAND flash memory or the magnetic disk media. This process is enhanced by an algorithm that dynamically learns the user's data access pattern and stores data accordingly to the appropriate tier. High speed access is achieved by storing frequently accessed data in the NAND flash memory. According to Toshiba, NAND flash cache improves read and write times by about three times compared to Toshiba's hard disk drives with equivalent capacities. In PCs, the new Hybrid Drive reduces application boot times by about 40%.