Solid State Disks (SSD)
In storage solutions,SSDs are used in three different scenarios:
– ascache memory (read and write cache) to speed up access to RAID systems or software defined storage,
– as fastest storage level in anauto-tiering solution, in which data is stored on different fast media according to criteria such as access frequency or age, or
– asAllFlash or FullFlash Storage with particularly high data access rates, especially for databases or in server virtualization.
The latter is a very strongly growing field of application due to falling prices and the increasing capacity of SSDs.
Important criteria for the selection are the “Drive Writes per Day” (DWPD), i.e. the maximum complete refilling of the disks per day during their warranty period. If it is exceeded, the SSD can reach the end of its life before the actual warranty period expires – and the warranty expires. However, this is only critical for cache disks, when all data of a large system flows through the SSD.