promise of superfast access speeds has been fulfilled by solid
state drives using NAND flash memory, but it comes at a high
monetary cost. Many enthusiasts, prosumers, and corporate users
have already adopted SSDs as hard drives are typically the
primary bottlenecks in a computer system. While CPUs and RAM
measure their access speeds in nanoseconds, traditional
magnetic-based hard disk drives are still measured in
milliseconds. advantage for HDDs is the low cost of production,
even for faster 7200 and 10k RPM drives. Samsung and Seagate
tried before to bridge the gap between low-cost HDDs and fast
SSDs using a hybrid hard drive, combining a single magnetic
platter with a small amount of NAND flash memory. The NAND would
act as a cache, similar in theory to a small scale tiered
storage solution like that used by many corporations for their
datacenters.However, the experiment failed. NAND was still too
expensive in 2007, and the small amount that was used proved
insufficient. Performance turned out to be worse