Performance of modern Java on data-heavy workloads
A very clear and interesting post.I've been trying to fit big-enough long-running stuff into JVMs for a few years, and have found that minimizing the amount of garbage is paramount.  Its a bit like games- or C programming.Recent JVM features like 8-bit strings and not having a size-limit on the interned pools etc have been really helpful.But, for my workloads, the big wastes are still things like java.time.Instant and the overhead of temporary strings (which, these days, copy the underlying data.  My code worked better when split strings used to just be views).There are collections for much more memory-efficient (and faster) maps and things, and also efficient (and fast) JSON parsing etc.  I have evaluated and benchmarked and adopted a few of these kinds of things.Now, when I examine heap-dumps and try and work out where more I can save bytes to keep GC at bay, I mostly see fragments of Instant and String, which are heavily used in my code.If there was only a library that did date manipulation and arithmetic with longs instead of Instant :(