Hybrid Hard Drive

A hybrid drive, hybrid hard drive (HHD), or hybrid hard disk drive (H-HDD) is a type of large-buffer computer hard disk drive. It is different from standard hard drives in that it integrates a cache using non-volatile memory or even a small solid-state drive (SSD or SSH drive). Although the cache typically uses non-volatile flash memory, some drives use battery-backed volatile RAM (a hybrid RAM disk). The flash memory buffer can speed up repeated reads to the same location; a RAM buffer speeds both reads and writes, but must be written to backup storage before power is lost.

The 5mm HDD "pairs MLC NAND flash storage for fast SSD-like data throughput and instant-on responsiveness with magnetic disks for efficient, high-capacity storage," Western Digital said.

"Similar to the practice of multi-million dollar enterprise systems, WD's hybrid technology utilizes the concept of tiered storage. Data accessed most frequently (often referred to as 'hot' data) is mana:ged using speedy NAND flash to ensure fast response times, while data accessed less often ('cold' data) resides on the robust magnetic disks," the company added.

Another benefit of hybrid disk drive technology is built-in backup—the magnetic disk in Western Digital's hybrid HDD backs up all files stored on the solid-state portion of the drive, the company said.

資料來源: http://en.wikipedia.org/wiki/Hybrid_drive

http://www.pcmag.com/article2/0,2817,2409528,00.asp