Various Hashing Improvements #660
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stevenewald
changed the title
| @@ -59,6 +59,20 @@ public class ByteArrayOrdinalMap { | |||
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| private long[] pointersByOrdinal; | |||
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| private static int nextLargestPrime(int num) { | |||
| int[] precomputedPrimes = new int[] | |||
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If we pick prime numbers close to these numbers that are also (2^n-1), then we can replace the modulo with simpler bitwise operations
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Good idea! Note the sizable gaps between sequential Mersenne primes (like 127 and 521), which might impact resizing memory efficiency. Considering we're not using modulo during LP, I think the current approach is acceptable.
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Restricting to mersenne primes will result in significant memory overhead -- each mersenne number is ~double the previous, and many of these are not prime, so an increase will often result in a significant step larger than doubling the space.
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Yeah they seem too few and far between 👍
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