On 07/11/2012 12:37 PM, Ferenc-Levente Juhos wrote:
> Precisely, I said the same thing a few posts before:
> dedup=verify solves that. And as I said, one could use dedup=<hash
> algorithm>,verify with
> an inferior hash algorithm (that is much faster) with the purpose of
> reducing the number of dedup candidates.
> For that matter one could use a trivial CRC32, if the two blocks have the
> same CRC you do anyway a
> byte-to-byte comparison, but if they have differenct CRC's you don't need
> to do the actual comparison.
Yes, and that's exactly what the Fletcher4+verify combo does (Fletcher
is faster than CRC32). That's why I started this thread - to assess
whether a better hash algorithm is needed and/or desired.
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