I’m slightly surprised there isn’t more KVM/Virtualized bare metal JVM environments. While I haven’t used it in a while, the decade+ I spent running Javan’s in production basically have the entire system over to the JVM (with some overhead for some small non-JVM background daemons). Most things were built not to use POSIX standards, but Java equivalents. Occasionally direct file system access for writes was necessary (logging being a big exception).

So giving the entire system to the JVM, performing some warmup prior to a service considering itself “healthy”, and the JVM was reasonably fast. It devoured memory and you couldn’t really do anything else with the host, but you got the Java ecosystem, for better or worse).

There was a lot of good tooling that is missing from other platforms, but also a ton of overhead that I am happy to not have to deal with at the moment.

Having a hard time finding it now, but someone put together a benchmark with two categories - naive and optimized - comparing implementations across languages with a workload vaguely resembling a real-world business application server with a mix of long and short lived objects. Java was at the top of the naive benchmark by a landslide and behind C and C++ (edit: and probably Rust) for the optimized ranking, but with a gap before the rest of the field.

With the JVM you basically outsource all the work you need to do in C/C++ to optimize memory management and a typical developer is going to have a hell of a time beating it for non-trivial, heterogenous workloads. The main disadvantage (at least as I understand) is the memory overhead that Java objects incur which prevent it from being fully optimized the way you can with C/C++.

I think it was this blog: https://renato.athaydes.com/all-posts They also tested common lisp!

Which post?

Some of those posts "404 The page you have entered does not exist"

> Having a hard time finding it now

So — Fastest at what, exactly? — is unanswered.