Storage

Updated: 2020-10-20

SATA

SATA: Serial Advanced Technology Attachment. SATA replaces PATA (Parallel ATA).

SATA Cables: one end plugs into a port on the motherboard, the other end into the back of a storage device.

SSD

  • data stored in semiconductor cells, one cell can contain between 1 and 4 bits of data

    • SLC: single bit cells, the most reliable, durable, fast, and expensive
    • MLC: 2 bits
    • TLC: 3 bits
    • QLC: 4 bits

SSD vs HDD

Manufacturers

  • HDD: a shrinking business, only 3 big players: Western Digital(largest market share), Seagate, Toshiba
  • Flash: Micron, Intel, Samsung, SK hynix, Kioxia (spun off from Toshiba, kioku: a Japanese work meaning memory, axia: a Greek word meaning value)

Memory vs SSD

  • Memory: volatile, byte-addressable
  • SSD: persistent, block-addressable

NVMe

NVM Express (NVMe) : use PCIe bus instead of SATA for SSD, reduces I/O overhead and brings various performance improvements relative to previous logical-device interfaces, including multiple, long command queues, and reduced latency.