This library provides a lock-free implementation of critnib — a cross between radix trees and D.J. Bernstein's critbit. The structure offers searches for equality and for next neighbour.
This implementation is restricted to fixed sized keys — an intptr_t in this library — even though the abstract data structure can support arbitrary key lengths. Lock-free mutations haven't been implemented either, although they're relatively easy to add. On the other hand, reads are strongly optimized, and do not require any kind of bus synchronizations (which are very costly on a many-core multi-socket machine).
That is, you will want this library if you need reads inside tight performance-critical loops but writes don't require this level of optimization.
This code has been developed at Intel as an internal part of PMDK, then extracted by the author and adapted for use as a stand-alone library. Thus, while the copyright and praise belong to Intel, this library is not a product supported or validated by Intel.