Recently we were looking at the Lexicographic byte array comparison in HBase. We did microbenchmark for the byte array comparator of HADOOP ( https://github.com/hanborq/hadoop/blob/master/src/core/org/apache/hadoop/io/FastByteComparisons.java#L161 ) , HBase Vs the latest byte array comparator from guava ( https://github.com/google/guava/blob/master/guava/src/com/google/common/primitives/UnsignedBytes.java#L362 ) and observed that the guava main branch version is much faster.
Specifically we see very good improvement when the byteArraySize%8 != 0 and also for large byte arrays. I will update the benchmark results using JMH for Hadoop vs Guava. For the jira on HBase, please refer