FarmHash

FarmHash is a non-cryptographic hash function developed by Google. It is designed to be fast and efficient for use in hash tables and other data structures where high performance is critical. FarmHash is a family of hash functions, with different variations optimized for different use cases, such as 32-bit and 64-bit output.

The primary goal of FarmHash is to produce a good distribution of hash values with minimal computational cost. This means that for a given set of input data, the hash function should produce a wide range of output values, and collisions (where different inputs produce the same hash) should be infrequent. This is essential for the efficient operation of hash tables, as it helps to minimize the number of elements that need to be searched linearly when a collision occurs.

FarmHash employs a combination of bitwise operations, additions, and multiplications to achieve its performance and distribution properties. It is known for its speed, often outperforming other popular non-cryptographic hash functions in benchmarks. Its design is based on principles that aim to leverage modern CPU architectures for maximum throughput.

While FarmHash is not suitable for cryptographic applications like password storage or digital signatures due to its lack of collision resistance against malicious attacks, it is a strong choice for general-purpose hashing in systems programming, data indexing, and in-memory data structures where speed is paramount and the input data is not adversarial. Its availability in various libraries makes it accessible for developers.