Re: JFFS3 & performance

Jörn Engel
2004-12-23T13:52:29Z

On Wed, 22 December 2004 12:14:18 -0600, xemc wrote:
>
> Please forgive me if this is a naive question, but isn't this data
> also protected by ECC in the first place? (or is that just for NAND?)

Just for NAND. NOR is pretty reliable anyway, so we could just go
without a checksum. Hard drive based filesystems usually do the same
and few people complain.
But as long as it's cheap enough, extra confidence doesn't hurt.

> How strong is this ECC compared to CRC32 or Adler32?

No idea.

> If the ECC can handle a few bit errors, then wouldn't a simple
> checksum handle the case where the file was completely corrupt or
> partially written?

Correct. Simple parity might be a nice reference as well. It is
really bad at catching even-bit errors (2,4,6,...), but it's fast.

Jörn

--
"Translations are and will always be problematic. They inflict violence
upon two languages." (translation from German)