The footprint of this particular service could have been optimized in Java but:

  1. the JVM itself imposes a high floor (hotspot, many shared libs loaded, ...)

  2. the Java language is full of overhead at every level (boxed types are a pet peeve of mine)

  3. the Java ecosystem has a tendency to regard memory as an inexhaustible resource, which lead a lot of waste in many 3rd party libraries

The core point is that optimizing this particular Java program (and the others that followed) would have been more time-consuming than a Golang rewrite and would have probably increased the complexity whereas a Golang rewrite reduced it.

Optimization was the original goal, increased maintainability was a pleasant result.

Point 2... yeah, that's one of my major problems with Java. Unnecessary boxing and the unreasonable amount of complexity if you work around it. In any type of Object collections, it consumes memory, stresses garbage collector unnecessarily and causes a lot of CPU cache misses.

Value types would help so much with this issue. I know they're coming one day. I hope Java/JVM can replicate memory efficiency and cache coherence of C++ std::vector for small objects.

34MB for Hello World, according to this SO post: http://stackoverflow.com/questions/13692206/high-java-memory...

I'm not going to install the JDK just to verify, but feel free to report back if you get different results.

For comparison... I did a similar Hello World test around the timeframe of .Net 2.0, and it was around 11mb to load IIRC. The latest iojs on windows seems to be just under 9mb.

Not sure what the golang overhead is, by comparison.

I can't say what an Hello World uses, but I have a Tumblr API → RSS gateway written in Go running for a few months, and it uses ~2MB.