alt Hacker NewsQuite the opposite, and the reason is that you can't extrapolate from small programs to large ones. Low-level languages (like C++) incur some significant overheads as they grow large (because of essential constraints of low-level languages that prevent them from doing certain optimisations that matter mostly in large programs), and these are exactly the overheads the JVM is designed to reduce. In small or short-lived programs, the situation is different, because Java does have some warmup costs and some fixed memory overheads that matter when you're small or short-lived. Go's compiler and GC are pretty basic, and are certainly good enough for smaller things, but don't scale as well to high workloads. Just the other day a colleague tested Caffeine, an old and well-established Java caching library, and Moka, a Rust caching library with the same workload. Caffeine had the same latency as Moka across all percentiles at twice the throughput.
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> because of essential constraints of low-level languages that prevent them from doing certain optimisations that matter mostly in large programs
Which specific optimizations are you referring to?
In my experience, this is largely a myth; compared to Rust, you actually get even faster code right away.
JIT is effective for languages where the source code lacks sufficient information (dynamic typing, where anything can be null).
> Caffeine had the same latency as Moka across all percentiles at twice the throughput.
Caffeine's next release has roughly 25% higher read throughput, with unchanged write throughput, thanks to fixing a false sharing mistake. That won't be visible in real workloads, but is fun nonetheless (500M reads/s on 8 cores).
I use Java every day but just to point out that your info about Go‘s GC seems out of date. They switched to Green Tea in 1.25 (I think?) - new GC that even has AVX-512 optimizations. Not sure what you mean by basic about the compiler but it‘s very fast and supports a large set of platforms. That‘s not basic to me.
We are using JDK25 and are considering rewriting parts of our product to Go because of lower memory pressure and faster startup time, i.e., cloud friendly. I actually love both languages.