This year, researchers from Carnegie Mellon University and Facebook investigated the reliability of flash-based solid-state drives (SSDs) in Google’s data centres. The study found that higher temperatures led to increased failure rates, most noticeably in SSDs that did not use throttling techniques to reduce data rates.

Based on the 2016 figures, the hard- drive failure rate continues to be on the upside. While SSDs have a failure rate of only 1.5 per cent over the same period, 20 per cent of flash drives developed irrecoverable errors over a four-year period. This is significantly higher than hard drives. Two- to three-year-old SSDs had a failure rate of three to four per cent, a much lower rate than those of hard drives.

SSDs are based on flash storage technology that allows data to be written, read and deleted multiple times. Hard disk drives (HDDs) use magnetic media to store their data, while SSDs use their integrated electronic circuits to store the data.

When solid-state drive (SSD) flash technology is used to store corporate data, the terms ‘flash drive’ or ‘flash array’ are often used. Flash memory is also solid-state technology because it uses integrated circuit technology; in order words, it has no moving parts. SSDs are a powerful, cost-effective and reliable data storage solution. It features a flash controller optimised to deliver high read and write performance by retrieving data both sequentially and randomly.

An SSD storage device is defined by its ability to store information using the reliable attributes of a permanent cluster of semiconductors. SSDs use NAND flash memory, where each chip contains a series of cells that are connected in series. NAND logic gate has become the preferred technology in recent years, offering advantages and disadvantages that go beyond the scope of discussion in this article, as well as faster deletion and write times, according to a recent study by the University of California, Berkeley.

Solid-state drives are a powerful, cost-effective and reliable data storage solution

The rates of improvement in the early days of hard disk storage show no signs of slowing down, as hard disks have served as a reliable storage solution since IBM first developed them in 1953.

SSDs contain no moving parts and weigh less than 1,000 grams per square centimetre. They cannot be broken down by unwinding or breaking up because they have no rotating magnetic media.

This makes SSDs much more durable than conventional hard disks and hard drives. Since the hard disk drive does not depend on moving parts like a rotating disk, the data is stored in a cluster of semiconductor memory banks.

Unlike a hard disk, an SSD is a non-volatile storage device that only stores data when it is connected to power. Basically, SSD drives are simply flash drives mounted on a computer or server and store the data in a flash memory bank. 

A hard disk relies on a rotating magnetic disk to read, write, and communicate data while storing information. Instead of storing data on rotating disks using magnetism, hard disk storage relies exclusively on the spinning disk and its reading head.

Hard drives can read and write data without having to communicate with other parts of the computer, such as the processor, memory or hard disk, while storing the information in the form of a magnetic disk, or a platter coated with magnetic material.

Solid-state hard drives (SSDs) that lack moving parts work slightly differently.  Instead of a hard disk and a SATA bus, SSDs use an embedded processor, a controller, to read and write data to a connected flash memory chip.

Solid-state drives continue to improve and augment data storage options and archival needs. They continue as a highly reliable medium for data persistence and information warehousing.

Performance wise, SSDs expand and exceed those earlier frameworks of traditional system designs using HDDs. The decreasing power needs of SSD further reduces the total cost of ownership as the diminished energy draw will increase savings over time.

Finally, price points for SSDs continue to narrow, and in time will match those of traditional hard drive models in a price per gigabyte (GB) comparison.

This article was prepared by collating various publicly available online sources.

Claude Calleja, Executive, eSkills Malta Foundation