There are not "plenty of variations"; they all measure roughly the same things--web framework, Postgres driver, JSON library. Go's postgres and JSON libraries a

There are not "plenty of variations"; they all measure roughly the same things--web framework, Postgres driver, JSON library. Go's postgres and JSON libraries are probably not well-optimized. Even if this isn't the case, at best it means that Java has a higher ceiling--it doesn't tell us about whether average Java code is faster than average Go code, nor does it tell us about how difficult it is to optimize code in each language such that it approaches its respective ceiling. Here are some more microbenchmarks that show Go and Java at about the same performance, and the rules of the game prohibit idiomatic Go optimizations (hence the poor performance on binary-tree; regex-redux is slow because Go's regex library is famously unoptimized). For real-world programs, Go and Java are in the same ballpark.