A solid state drive is a secondary storage device made with solid state electronic components for use in computers in place of a conventional hard disk drive, such as auxiliary memory or for the manufacture of hybrid units composed of SSD and hard drive.
consists of a nonvolatile memory, instead of turntables and head, which are found in conventional hard drives. No moving parts, solid state drive aims to drastically reduce the search time, latency, and others, hoping to positively differentiate their hard drive cousins.
Being immune to external vibrations, makes it especially suitable for use in mobile computers (eg installed in airplanes, cars, laptops, etc.).. Advantages
solid state devices based on Flash have several unique advantages:
* Faster startup. * High speed
writing
* Faster reading - even more than 10 times longer than traditional hard drives faster through internal RAIDs in a single SSD.
* Low latency read and write, hundreds of times faster than mechanical disks.
* Launch applications and boot in less time - result of faster read and especially on search time. But only if the application resides in flash and is more dependent on reading speed than others.
* Lower power consumption and heat production - result of having no mechanical parts.
* No noise - the same lack of mechanical parts makes them completely inaudible.
* Improved MTBF up to 2 million hours, far superior to hard disks that do not reach 1 million
* Security - allows a very quick "cleaning" of the stored data.
* deterministic performance - unlike mechanical hard drives, performance of SSDs is constant and deterministic across the entire storage. The time to "search" constant, and performance does not deteriorate while the medium is full. (See Defragmentation)
* Lower weight and (depending on type) size.
* Resistant - Supports shock and vibration without spoiling and without decalibrate as happened with former
* Erase Hard Drives safer and irrecoverable data
Disadvantages
solid state devices based on flash are also several Disadvantages:
* Price - The flash memory prices are considerably higher, and the main reason for its low demand.
* Lower recovery - after a mechanical failure data is completely lost because the cell is destroyed, whereas in a normal HDD suffers mechanical damage data is often recoverable using experts.
* Vulnerability against certain kinds of effects - including abrupt power loss (especially DRAM based SSDs), magnetic fields and static charges compared to normal hard drives (which store data inside a Faraday cage).
* Capacity - Today, have less capacity than a conventional hard disk that reaches to 2.5 Terabytes
Old Disadvantages and solved:
* performance degradation after long use NAND (solved TRIM)
* Minor speed I / O operations sequentially. (We have already achieved a similar speed)
