scrubbing and dedup

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scrubbing and dedup

Postby haer22 » Sat May 24, 2014 2:23 pm

Will dedup have any impact on scrubbing? Besides scrubbing the dedup-table.

I.e., will the block be de-dupped before the checksum is checked?
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Re: scrubbing and dedup

Postby ilovezfs » Sat May 24, 2014 8:50 pm

No scrub is in no way a means to apply compression or to apply dedup to data already written to a file-system dataset. You would need to create a brand new file-system dataset with compression and/or dedup enabled, and rsync the data from the old dataset to the new dataset.
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Re: scrubbing and dedup

Postby haer22 » Sun May 25, 2014 1:23 am

Oh, I understand that scrubbing does not change anything. just checking the current data.

What I am asking is about the scrubbing, is the scrubbing slowed down in anyway if the data is de-dupped?

My understanding is that it checks the checksum of a FSB, regardless if that FSB is a compressed one or whatever. Just want that verified.
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Re: scrubbing and dedup

Postby ilovezfs » Sun May 25, 2014 1:38 am

Scrub checks the checksum for each block. It has nothing to do with dedup.
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Re: scrubbing and dedup

Postby haer22 » Sun May 25, 2014 1:50 am

Thanks for the verification.
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