Flash Storage

1. uses electricity and has no mechanical parts
2. Typically consumes 20% of the power than traditional mechanical hard drives.
3. typically reads more than one hundred times faster than traditional mechanical hard drives.

Data center managers looking for ways to address the energy drain represented by hard drives are examining flash storage as a way to achieve green computing or green data center benchmarks. Businesses with I/O-intensive applications, such as credit card processing systems, have also found flash storage to be efficient and cost-effective. As a result, enterprise storage providers like EMC, chip makers like Samsung and server manufacturers like Sun Microsystems have all entered the flash storage market.

Most flash storage systems Are composed of:

1. a memory unit - used to store data
2. an access controller - manages and controls access to the storage space on the memory unit

Flash storage may consist of:

1. a single solid-state drive (SSD) in a laptop
2. a hybrid hard drive (HHD) - that contains both a conventional hard drive and a flash memory module.

Data is written onto

1. NAND flash memory - which is primarily used in main memory, memory cards, USB flash drives, solid-state drives, and similar products, for general storage and transfer of data
2. NOR flash memory - which allows true random access and therefore direct code execution, is used as a replacement for the older EPROM and as an alternative to certain kinds of ROM applications, whereas NOR flash memory may emulate ROM primarily at the machine code level
3. or a combination of the two.

Caviet

As interest in flash storage has grown in the market, some industry watchers have also pointed out a frequently overlooked caveat with flash: while its random read access is far superior to traditional hard drives, flash write speeds are lower than their mechanical counterparts, especially in the single-level cell (SLC) devices typically sold to the enterprise. For this reason, and because of flash's relatively limited tolerance for write-erase cycles, users must carefully select and provision data for this medium.