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From: ebiederman@lnxi.com (Eric W. Biederman)
Date: 27 Jan 2005 23:08:36 -0700
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Cc: David Woodhouse <dwmw2@infradead.org>,
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Subject: Re: JFFS3 & performance
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Jared Hulbert <jaredeh@gmail.com> writes:

> > Guess we'll have to agree to disagree then :).  All I know is that I
> > want to be damn sure that the data I'm returning isn't totally screwed.
> > Call me paranoid.  A checksum is the only way I know of doing that.
> 
> Paranoid :)

Only insane programmers are not paranoid.

> To humor those of us willing to take our chances trusting the media
> won't go bad, would it be possible to architect JFFS3 such that
> disabling the checksumming or stripping it out is possible with out
> too much pain?

But checksums protect against more than the reads going bad.  They
also protect against writes going bad.  With large volumes of use
write errors are almost a certainty, with NOR.  And if you miss the
fact that the error happens.  And a single bad write is especially
painful if you are writing compressed data.

If you just need reads something like romfs, or isofs tuned for from a
NOR flash chip is probably better.

Eric