[spreiti]

This a 1000 times. People like to hate on Java but when there are problems to diagnose on production systems it is second to none.

But from my experience most people don't know these tools even exist so the only thing they do is restarting and guessing where the problem might be if it persists.

[cogman10]

Flight recorder is a godsend and I've not seen it's equal in any other language/ecosystem.

Any JVM anywhere can answer the question "why am I running slow" with a quick run of flight recorder. Memory, CPU, socket time, GC impact, TLB, thread dumps, etc. It's all there in one file that imposes something like a 1->2% performance impact if you run it constantly.

It's just so good.