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f483

Re:Déjà vu: Fast efficient probabilistic deduplication on Saturday July 15, 2017 @08:45AM (#14776391)
Thanks for the feedback, will look into it.
Re:Déjà vu: Fast efficient probabilistic deduplication on Saturday July 15, 2017 @06:29AM (#14775980)
> Bloom filters are of course interesting in certain scenarios e.g. to statistically reduce network traffic.

Yes I originally wrote it for exactly this such a scenario.

This is not for you if you cannot live with any chance of a false positive, even an extremely small one. Note that even in most cases a false positive is acceptable if the chance of a false positive is less then the chance of a hardware error.

Not that just because it is probabilistic does not mean its not useful in many cases. The default setup with 1mil entrie memory and 1/1mil chance false positive chance will run at ~8M mem usage. This is a quite an acceptable trade off in many cases.

Re:Déjà vu: Fast efficient probabilistic deduplication on Saturday July 15, 2017 @06:17AM (#14775954)
> Could you use this to deduplicate files in a filesystem?

Depends on what you mean and your constraints. Deduplicate file entries if you can live with a rare false positives, sure. A setup of 1million entrie limit with 1/1billion false positive chance will get ~80M mem usage.

If you want to check for duplicate files, probably not.

> Could you use this as the deduplication method in ZFS?

I would say no.

Re:Déjà vu: Fast efficient probabilistic deduplication on Saturday July 15, 2017 @05:13AM (#14775784)
Sorry I cant do magic just yet :(
Yeah, should have put more thought into it then I did. But I guess its to late now.