The Evolution of Disk Storage and an Introduction to NVMe

A lineup of Standard HDDs throughout Their History and across All Form Factors (by Paul R. Potts—Provided by Author, CC BY-SA 3.0 us, disk drive’s performance typically is calculated by the time required to move the drive’s heads to a specific track or cylinder and the time it takes for the requested sector to move under the head—that is, the latency. Now, although HDDs’ performance has been increasing with newer disk access protocols—such as Serial ATA (SATA) and Serial Attached SCSI (SAS)—and technologies, it’s still a bottleneck to the CPU and, in turn, to the overall computer system. This is a hardware cache built in to the processor module and utilized by the CPU to reduce the cost and time it takes to access data from the main memory (DRAM).

Source: www.linuxjournal.com