> So basically it seems that given a large enough flash drive with decent >
> wear levelling the lifetime should be completely ample...> > ...Thats the
> theory anyway.> > I feel quite bullish about the whole thing, but I think I
> would avoid > the *really* discounted cheapo flash drives since they may not
> have the > correct wear levelling. Decent brand names should be fine though
> (and > you can google for details on their specs)
Hi
Yeah we contacted a distributor of PQI flash memory. They sent us a wear
leveling formula.
Here it is:
Example: A 256MB flash device writing 128KB data into flash device the formula
as below: ( With wear leveling ).
DOM Lifetime ( Theory ) = (256MB-100MB)*100K*0.95 / (128KB/sec) *60*60*24=
1340.06 days
# “0.95” : After the flash being format the capacity might lower than the
certain capacity.# “60*60*24” : 86400 writing times per day. 1 time /sec#
”100MB” : The size of your OS & AP. In this case we set it as
“100MB”#“128KB/sec”: The data size that writing onto flash device per second.#
”100K” : The limitation of flash memory’s P/E cycles.
P.S. : NAND type flash (Small block) : 1 Block = 32 page * 512byte = 16KBNAND
type flash (Large block): 1 Block = 64 page * 2Kbyte = 128KBIf the data less
than 128KB we recommend you still calculate it with 128KB.
NOW.. I am truly confused :)
Juan
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