MurmurHash is a non-cryptographic hash function suitable for general hash-based lookup, [1][2][3]. It was created by Austin Appleby, and exists in a number of variants, all of which have been released into the public domain.
Variants
The current version is MurmurHash2, which yields a 32-bit hash value and is optimized for Intel processors. Slower versions of MurmurHash2 are available for little-endian and aligned-only machines. The MurmurHash2A variant adds the Merkle-Damgard construction so that it can be called incrementally. There are two variants which generate 64-bit values; MurmurHash64A, which is optimized for 64-bit processors, and MurmurHash64B, for 32-bit ones. MurmurHash1 is obsolete.
Implementations
The canonical implementations are in C++, but there are efficient ports for a variety of popular languages, including Python[4], C#[5], Perl[6], Ruby[7], and Java[1].
It has been adopted into a number of open-source projects, most notably libmemcached[8] (the C driver for Memcached), maatkit[9], and Hadoop[1].