On Jan 11, 2008 3:38 PM, Eric Johnson <ericlj63@gmail.com> wrote:

On Jan 11, 2008 3:18 PM, Luke -Jr <luke@dashjr.org> wrote:
> On Friday 11 January 2008, gary hildebrand wrote:
> > I would say since those thumbdrives are solid state, theoretically they
> > should last forever, barring fire, flood, act of God, or static discharge .
>
> Uh, no. Flash drives are known to have a limited number of writes after which
> they get stuck. That's why you never put swap on a Flash drive.

Agreed. Run without swap if you are running off of flash, unless you
like making trips to MicroCenter.

There is a significant lifetime difference between low and high
density flash. (I forget the actual technical names.) The low density
lasts longer and it is also faster. Technically, this is because each
memory location in the low density holds one bit (and is read simply
high or low) while the high density holds 2 bits per location (which
requires more precise reading of intermediate steps).

The difference in lifetime is roughly "It will last a year" versus "It
will last until I die". The difference in cost is pretty significant,
also. The good ones are the high-end, high-speed ones sold mainly for
photography purposes.

---

I just looked it up - it's SLC vs MLC.
http://www.edn.com/index.asp?layout=partnerContentDetail&articleid=CA6319917

--

Eric Johnson

"Where your pleasure is, there is your treasure: where your treasure,
there your heart; where your heart, there your happiness."
Saint Augustine
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Ok -a stated i another thread- The device I a trying to use is an actual hard drive just a very small one. it's called a Microdrive and they are the heart of
smal hs based music players. There was a time when certain players had a street price of 1/3 the cost for that size microdrive itself! Which caused some OEM embedded drives to be BROKEN BY DESIGN from having such "Drive Harvesting" possible. The sordid details might take some Google Fu but it's documented. Perhaps a new thread on Linux rescuing such borked in firmware itemes is in order?

Well- the device I am using seems made for projects like mine.
There are IDE to CF converting units that a CF microdrive can run from, but the Zen of a detachable USB device as a microcosm is more elegant. Here's the pitch on Gary's idea.We use one FAST expensive drive as Write once read many,. and CHEAP disposable drives as flash drive. Being serious- how much use will it thke to kill even a swap device? Then we look at a 1gb device being Eight bucks- ok we round it up to ten to cover travel and taxes etc.Ten bucks a GB for "Sacrificial Flash" may be an experiment worth kicking around?
And I have a WtF inducing concept beginning a new thread. HINT: How many USB drives can Linux support at once?