protected static long rotl64(long v, int n) {
    return ((v << n) | (v >>> (64 - n)));
  }
This is a very fast, non-cryptographic hash suitable for general hash-based
lookup. See http://murmurhash.googlepages.com/ for more details.

hash32() and hash64() are MurmurHash 2.0.
hash3_x64_128() is MurmurHash 3.0.

<p>
The C version of MurmurHash 2.0 found at that site was ported to Java by
Andrzej Bialecki (ab at getopt org).
</p>
ambry-utils/src/main/java/com/github/ambry/utils/MurmurHash.java