Re: Lifetime of flash memory

From: Artem B. Bityutskiy
Date: Sun Mar 26 2006 - 11:33:55 EST


linux@xxxxxxxxxxx wrote:
Sorry, I don't have anything in particular, just bits I've picked up
talking to CF manufacturers.

Basically, a CF card is a flash ROM array attached to a little
microcontroller with an IDE interface. The large manufacturers generally
have custom controllers.

I'm actually interested in:

1. CF wear-levelling algorithms: how good or bad is it?
2. How does CF implement block mapping, does it store the mapping table on-flash or in memory, does it build it by scanning, how scalable are those algorithms.
3. Does CF perform bad erasable blocks hadling transparently when new bad eraseblocks appear.
4. How tolerant CF to powrer-offs.
5. Is there a Garbage Collector in CF and how clever/stupid is it.

etc.

I've heard CF does not have good characteristics in the above mentioned aspects, but still, it would be interesting to know details. I'm not going to use CFs, but as I'm working with flashes, I'm just interested. It'd help me explaining people why it is bad to use CF for more serious applications then those just storing pictures.

--
Best Regards,
Artem B. Bityutskiy,
St.-Petersburg, Russia.
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/