Application startup time usually is dominated by class loading, JITs and actual application initialization code. GC overhead should be fairly small unless the h

Application startup time usually is dominated by class loading, JITs and actual application initialization code. GC overhead should be fairly small unless the heap is badly sized. You might be able to shave off a few milliseconds by tuning the GC, but the lion's share is somewhere else. You could try OpenJ9 for CLI tools which claims to offer faster startup times out of the box compared to openjdk. Tweaking the JIT behavior (number of compiler threads, compilation thresholds for the tiers etc.) or using CDS can help too.