pub fn bloom_bits_per_key(entries: usize, false_positive_rate: f64) -> usize {
        let size =
            -1.0 * (entries as f64) * false_positive_rate.ln() / std::f64::consts::LN_2.powi(2);
        let locs = (size / (entries as f64)).ceil();
        locs as usize
    }
Get bloom filter bits per key from entries count and FPR
mini-lsm-mvcc/src/table/bloom.rs