I don't think any of your description about how the JVM GC works is accurate. The default GC is generational so it generally does lots of garbage collection be

I don't think any of your description about how the JVM GC works is accurate. The default GC is generational so it generally does lots of garbage collection before it takes up the reaches the heap limit. I assume what you really want is for the Java heap to return memory to the OS. The default JVM GC isn't configured to do that but you can easily configure the JVM to do that. > JVM is such a failure I'm genuinely confused why you would consider that to be the case. Especially since your preferred alternative (WebASM) is just about as bad or worse by your stated measures (start up time, GC).