[FreeBSD-Announce] Foundation Announces NAND File System for FreeBSD Project

[Freddie Cash]

On Fri, Mar 2, 2012 at 7:30 AM, Julian H. Stacey <jhs at berklix.com> wrote:
> Hi freebsd-fs at freebsd.org
> cc Deb
>
> Deb Goodkin wrote to announce@ Thu, 01 Mar 2012 11:45:53 -0700 (19:45 CET):
>> The FreeBSD Foundation is pleased to announce that Semihalf, an
> ...
>
> I was interested to read more background, but no URLs,
> so I found http://www.semihalf.com/ & re.
>        NAND Flash File System
> found:
>  http://en.wikipedia.org/wiki/Flash_memory#NAND_flash
>        "Manufacturers try to maximize the amount of usable storage
>        by shrinking the size of the transistor below the size where
>        they can be made reliably, to the size where further
>        reductions would increase the number of faults faster than
>        it would increase the total storage available."
>        -
>   Really scarey if that is taken literaly, I jhs@ presume loose phraseology,
>        hopefully someone who knows more will rephrase that :-).

A good primer on NAND Flash with lots of info on "the next hot thing",
triple-level cell (TLC) flash, which has all the flaws of MLC
multiplied many times over, but is a lot less expensive to use/make,
so expect it to hit consumer drives this year.  :(  Page 3 is
extremely enlightening about the issues, especially regarding the
increased CRC requirements in order to actually read a valid bit from
the cell.

-- 
Freddie Cash
fjwcash at gmail.com