Mass Storage Technologies Flashcards
Traditionally composed of individual disks/platters with read/write heads on actuator arms controlled by a servo motor - all contained in a sealed case that prevents contamination by outside air
Hard Disk Drive (HDD)
Measurement of how fast the spinning platters spin, measured in revolutions per minute (RPM)
Spindle Speed
Data storage device that uses flash memory to store data
Solid-State Drive (SSD)
A form of multi-level cell (MLC) that stacks vertically, providing increased density and capacity. Most popular type of memory technology in SSDs
3D NAND
Measures how quickly it responds to a single request. Usually expressed in milliseconds or microseconds
Latency
Windows supported drives that combine flash memory and spinning platters to provide fast and reliable storage. Aka SHHDs.
Hybrid Hard Drives (HHD)
Apple’s version of hybrid hard drive
Fusion Drive
A series of hard drive standards defining both the older parallel ATA (PATA) and modern serial ATA (SATA) drives
Advanced Technology Attachment (ATA)
Implementation that integrates the controller on the disk drive itself
Parallel ATA (PATA)
Unique 40-pin ribbon cables used by PATA drives that are usually plugged directly into a system’s motherboard
IDE Cables
An internal drive program that tracks errors and error conditions within the drive
Self-Monitoring, Analysis and Reporting Technology (S.M.A.R.T.)
Serialized version of the ATA standard that offers many advantages over PATA technology, including thinner cabling, keyed connectors, and lower power requirements
Serial ATA (SATA)
Connects SATA devices to the expansion bus
Host Bus Adapter (HBA) or SATA Controller
Version of SATA that ties capable drives directly into the PCIe bus on motherboards. Each lane of PCIe 3.0 is capable of handling up to 8 Gbps of data throughput
SATA Express (SATAe) or SATA 3.2
Serial ATA-based connector for external hard drives and optical drives
External SATA (eSATA)
18 inch cable length
PATA
1 meter cable length
SATA
2 meter cable length
eSATA
An efficient way to work with SATA HBAs. Unlocks some of the advanced features of SATA (hot-swapping and NCQ)
Advanced Host Controller Interface (AHCI)
A disk optimization feature for SATA drives enabling faster read and write speeds
Native Command Queuing (NCQ)
Specification supports a communication connection between the OS and the SSD directly through a PCIe bus lane, reducing latency and taking full advantage of the fast speeds of higher-end SSDs. Most common format is M.2
Non-Volatile Memory Express (NVMe)
Long-lived storage drive technology once common in the server market. Has been through many iterations. Today, the command set lives on in Serial Attached SCSI (SAS) hard drives
Small Computer System Interface (SCSI)
Fast, robust storage interface based on the SCSI command set. Also support SATA drives. Used mainly in servers and storage arrays
Serial Attached SCSI (SAS)
The process of reading and writing data at the same time to two drives
Disk Mirroring
Type of disk mirroring using two separate controllers rather than one; marginally faster than traditional mirroring because one controller does not write each piece of data twice
Disk Duplexing
Process by which data is spread among multiple (at least 2) drives. Increases speed for both reads and writes of data. Considered RAID level 0 because it does not provide fault tolerance
Disk Striping
Method for providing fault tolerance by writing data across multiple drives and then including an additional drive (parity drive) that stores information to rebuild the data contained on the other drives. Requires at least three physical disks: two for the data and a third for the parity drive. This provides data redundancy at RAID levels 5, 10, and 0+1 with different options
Disk Striping with Parity
2+ drives working as a unit
Array
Uses Mirroring or Duplexing for increased data redundancy
RAID 1
Disk striping with distributed parity - uses block-level and parity data striping; requires 3+ drives
RAID 5
Uses byte-level striping and provides no fault tolerance
RAID 0
A RAID 0 configuration created by combining two RAID 1s. Provides both speed and redundancy but requires at least 4 disks
RAID 0+1
Disk striping with extra parity. Like RAID 5, but with more parity data. Requires 4+ drives but you can lose up to 2 drives at once and your data will be protected
RAID 6
The opposite of RAID 0+1, two mirrored RAID 0 configurations. Provides both speed and redundancy, and also requires 4 disks
RAID 10
Process through which new disks are automatically recognized by the BIOS
Autodetection
