The standard pure Java version (master branch) is highly optimizied but the conversion of user data block with little-endian semantics to the long[]
m registers of the algorithm in compress() is a performance bottleneck. That said the master branch version performs
substantially better than other pure Java libraries.
The unsafe version (unsafe branch) addresses this bottleneck and achieves ~ 4.1 byte/cycle on a fairly dated i5 1.3 MHz
MacBook Air. This compares rather favorably with the 3.08 bytes/cycle noted on the official Blake2b
site. To close that gap would likely require use of SIMD operations which can not (afaik) be done in pure Java. (unsafe is
only used to efficiently convert the compress'd block byte[] to long[]. No non-JVM-managed memory operations are performed, so
this should be your choice if you are OK with use of the use unsafe package.)
This library includes a benchmark utility which you can run using the provided jars in lib/ (or directly in the master or
unsafe branch).
java -cp <your choice of the 2 jars> ove.crypto.digest.Bench -d <digest-name>
The comparative results (per machine spec above) are Bench runs for both variants of this library's Blake2b, MD5, sha1,
sha-256, sha-512, and Bounch Castle version of the Blake2b algorithm.
