On 07/11/2012 10:41 AM, Ferenc-Levente Juhos wrote:
> I was under the impression that the hash (or checksum) used for data
> integrity is the same as the one used for deduplication,
> but now I see that they are different.
They are the same "in use", i.e. once you switch dedup on, that implies
checksum=sha256. However, if you want to you, you can force ZFS to use
fletcher even with dedup by setting dedup=verify and checksum=fletcher4
(setting "dedup=on" with fletcher4 is not advised due to fletcher's
possibility of producing collisions and subsequent silent corruption).
It's also possible to set "dedup=verify" with "checksum=sha256",
however, that makes little sense (as the chances of getting a random
hash collision are essentially nil).
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