How to calculate the redis memory usage of CountingBloomFilterRedis

Baqend / Orestes-Bloomfilter

Library of different Bloom filters in Java with optional Redis-backing, counting and many hashing options.

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Open techzhou opened 5 years ago

techzhou commented 5 years ago

For example,

new FilterBuilder(1000000, 1e-5)

when it full （added 1000000 elements）

how much memory it cost. is there any calculation method?

kangwen commented 3 years ago

N (added elements , 1000000 eg.) f (falseProbability, 1e-5 eg.) M (total bit)： M = - N ln(f) / ln2^2.
K(hash functions)： K = max(1, ln2 M/N)