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Music servers and other computer based digital audio technologies.

Modern SSD vs HDD

Most modern SSD's and filesystems are a lot better than they were just a few short years ago. I no longer concern myself with a normal amount of writes from the OS and applications writing into logs and temp files. Of course I wouldn't run a "write test" all day long as that wouldn't be "normal".


There are four common types of NAND flash used in SSD's, differing in number of P/E cycles per lifetime, and defined by their construction:

SLC -- Single Level Cell: the most expensive, longest lived (high P/E), and generally fastest. Bits are stored only as 2 voltage levels, or a "1" or "0." In SLC less data is stored per cell, so the per unit storage cost is higher. SLC is ridiculously expensive and has fallen out of favor in IT data center applications. It's still used in highly specialized applications.
eMLC -- Enterprise (grade) Multi-Level Cell: is MLC with longer life, usually because of an advanced controller operating the cell and error recovery techniques, construction density, or some combination of the two. These often allocate more cells for wear leveling than MLC.
MLC -- Multi-Level Cell: is consumer grade and used in phones, cameras, and USB sticks, laptops, etc. The stored charge in MLC may be interpreted as a variety of values, 0 to 3, or 4 possible states, and may store 2 bits. With shorter lifetimes, usually 10x less than SLC, the advantage of this memory is that the cost is several times less than SLC, but with lower write speeds. MLC typically uses some form of error correction code per block.
TLC -- Triple Level Cell: championed in some Samsung models, TLC has higher power and error correction requirements, and higher wear levels. TLC is targeted at environments with predominant read uses, and has not been commonly used. Samsung makes excellent MLC and eMLC SSDs but they also have their "cheap line" of TLC based SSDs.

We use eMLC in the data center. I use MLC SSDs in my computers. TLC is the cheapest but I wouldn't use TLC in any of my computers or music servers.





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