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Comment by verall

4 years ago

> reflush to the MLC

I'm nitpicking, but an EVO has TLC. Also an SLC write cache is the norm for any high performance consumer ssd, it's not just Samsung.

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verall

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fire  4 years ago

> I'm nitpicking, but an EVO has TLC.

b...but the M in MLC stands for multi... as in multiple... right?

checks

Oh... uh; Apparently the obvious catch-all term MLC actually only refers to dual layer cells, but they didn't call it DLC, and now there's no catch-all term for > SLC. TIL.

  • marcan_42  4 years ago

    The "L" stands for level, and that makes it even more wrong. MLC should have been been QLC or DBC, and TLC should have been OLC or TBC. It's two bits and four levels, or three bits and eight levels. The latest "QLC" flash has 16 levels (and is a massive step down in performance and reliability; it seems TLC is the sweet spot, at least right now, unless you really want the absolute cheapest, performance be damned).

    Interestingly enough, Apple has a patent for 8-bit cell flash (256 levels!), going full blown analog processing and error correction, but I don't think that ever became a product.

supermatt  4 years ago

Thanks, I thought this was a special Samsung feature. They certainly advertise it as such!

fomine3  4 years ago

I believe now SLC cache is available on every TLC consumer SSDs, because it's slow without it.

  • wtallis  4 years ago

    I'm not sure there were ever consumer TLC SSDs that didn't use SLC caching (except for a handful that use MLC caching). SLC caching was starting to show up even in some MLC drives when the market was transitioning from MLC to TLC, and now there are even some enterprise drives that use SLC caching.

  • verall  4 years ago

    See I wanted to say "every" but I just know there exists some crap slow drive without one that survives because it is technically an "S S D".

    Even Samsung's last MLC drives (970 Pro?) had SLC write caches. Otherwise they'd just be giving up a benchmark.

    Enterprise is a whole different game tho, as the value of an SLC cache is inversely proportional to the write duty cycle...