A conservative GC is easier to implement. No other reason.

Thanks, the tutorial is gone (replaced by the tour) and we just removed the link from the blog page.

"Go Pro" is unfortunately a very misleading name. I just spent an hour cleaning up his use of Go. Nobody made any attempt to actually turn this code into a well-written Go program. I did not realize that he was going to publish it externally.

Would you consider touching up the Go version again to make it more idiomatic and well written? I'd be interested in seeing good Go examples; I'm sure many others here would as well.

The Go distribution already contains plenty of idiomatic, well written and very readable code.

It would be interesting if you did the necessary optimization and posted your results for a better comparison.

I only spent an hour straightening out his use of Go. Had I know he was going to publish it externally as "Go Pro" I would have tried to turn it into a real Go program, and perhaps even optimize it somewhat. Overall I think the Java and C++ code got the most attention from language experts. Ah well.

From the Java Tunings section of the paper:

Note that Jeremy deliberately refused to optimize the code further, many of the C++ optimizations would apply to the Java version as well

It sounds like Jermey didn't spend much time tuning the Java version either.