This is a port of the Murmur3 hash function. Murmur3 is a non-cryptographic hash, designed to be fast and excellent-quality for making things like hash tables or bloom filters.

This is a port of the C implementation by Peter Scott. We only use x86/128 so this is the only implementation we have.

All code lives in murmur package. Signatures and code in general are kept as similar to C implementation as possible.

func MurmurHash3_x86_128 (key []byte, seed uint32) ([2]uint64)

The interface is: You give a key, a byte slice of the data you wish to hash; seed, an arbitrary seed number which you can use to tweak the hash. You get an array of two uint64 (Go <= 1.9 does not yet have a uint128).

The hash functions differ in both their internal mechanisms and in their outputs. They are specialized for different use cases:

MurmurHash3_x86_32 has the lowest throughput, but also the lowest latency. If you're making a hash table that usually has small keys, this is probably the one you want to use on 32-bit machines. It has a 32-bit output. (not yet ported)

MurmurHash3_x86_128 is also designed for 32-bit systems, but produces a 128-bit output, and has about 30% higher throughput than the previous hash. Be warned, though, that its latency for a single 16-byte key is about 86% longer! (ported - for LittleEndian only)

MurmurHash3_x64_128 is the best of the lot, if you're using a 64-bit machine. Its throughput is 250% higher than MurmurHash3_x86_32, but it has roughly the same latency. It has a 128-bit output. (not yet ported)

All this code is in the public domain. Murmur3 was created by Austin Appleby, and the C port and general tidying up was done by Peter Scott. The Go port was done by Andreas Bergmeier and licensed under Apache License 2.0.