Haveged is an easy-to-use, unpredictable random number generator based upon an adaptation of the HAVEGE algorithm.

It was created to remedy low-entropy conditions in the Linux random device that can occur under some workloads, especially on headless servers.

The havege algorithm gathers the random timing variations encountered in benchmarking a PRNG calculation. The calculation is constructed to be sensitive to the effects of hardware interrupts and the output continually reseeded by XOR differences of successive iterations of the benchmark.