ZFS License and Future

[Roland Smith]

On Mon, Nov 08, 2010 at 09:44:29PM +0100, C. P. Ghost wrote:
> On Mon, Nov 8, 2010 at 7:38 PM, Roland Smith <rsmith at xs4all.nl> wrote:
> > On Mon, Nov 08, 2010 at 05:08:33PM +0100, Svein Skogen (Listmail account) wrote:
> >> But it's still not capable of true forward-error-correction. If we are
> >> to embark upon creating a new solution, using something that is cheap
> >> for "normal cases" but can still be used (albeit more expensively) for
> >> error recovery would (imho) be better. Even if that means we get less
> >> net storage out of the gross pool (it could perhaps be configurable?)
> >
> > I'm not sure what you mean by "true forward-error-correction". But if you want
> > to make _really sure_ that a spinning disk hasn't mangled the data you should:
> 
> Maybe something like Reed-Solomon ECC in different blocks.
> Should a data block go bad, it could be rebuilt on-the-fly from
> those ECC blocks:

And how do you detect that a block has gone bad, other than reading back what
you wrote and finding a difference? Because that would still be slow.

Roland
-- 
R.F.Smith                                   http://www.xs4all.nl/~rsmith/
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