If you haven't checked it out yet, GraalVM's Native Image [1] already let's do AOT compilation suitable for distribution. You have to do some configuration to deal with reflection and dynamic class loading since there's no JVM in the produced build, but it comes with tooling to simplify that. And that restriction is being addressed by Project Crema [2].
The slight drawback is that AOT compiled Java code's performance isn't as good as the JIT compiled form running on the JVM.
There's a reason why folks keep coming back to JIT compilation. It's hard to beat the value that can be gained from actually gathering data on how the code is actually used, which leads to a whole set of potential optimisations (which is the problem Profile Guided Optimisation attempts to solve for AOT compiled code.) The JVM is arguably one of the most advanced and capable JITing runtimes.
As with anything it's a trade off. Fast start times, pretty fast running (I think maybe less memory usage?); vs the full JIT speed you can get on the JVM at the cost of start-up speed and memory consumption. All depends on what you want to use the application for.
If you're talking something like a serverless function, go native. If you're talking production server where you're measuring runtime in more than dozens of minutes, probably better to stick to the JVM & JIT.
Full agreement with everything you said. Just one detail to add on serverless (and potentially in a scheduled environment like k8s), startup time can be an order of magnitude or more faster in a native build. For instance, I have some quarkus applications that can take 10 seconds to ready running via the jre that take 10ms or less to start as a graalvm built binary.
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If you haven't checked it out yet, GraalVM's Native Image [1] already let's do AOT compilation suitable for distribution. You have to do some configuration to deal with reflection and dynamic class loading since there's no JVM in the produced build, but it comes with tooling to simplify that. And that restriction is being addressed by Project Crema [2].
[1] -- https://www.graalvm.org/latest/reference-manual/native-image... [2] -- https://github.com/oracle/graal/issues/11327
The slight drawback is that AOT compiled Java code's performance isn't as good as the JIT compiled form running on the JVM.
There's a reason why folks keep coming back to JIT compilation. It's hard to beat the value that can be gained from actually gathering data on how the code is actually used, which leads to a whole set of potential optimisations (which is the problem Profile Guided Optimisation attempts to solve for AOT compiled code.) The JVM is arguably one of the most advanced and capable JITing runtimes.
As with anything it's a trade off. Fast start times, pretty fast running (I think maybe less memory usage?); vs the full JIT speed you can get on the JVM at the cost of start-up speed and memory consumption. All depends on what you want to use the application for.
If you're talking something like a serverless function, go native. If you're talking production server where you're measuring runtime in more than dozens of minutes, probably better to stick to the JVM & JIT.
Full agreement with everything you said. Just one detail to add on serverless (and potentially in a scheduled environment like k8s), startup time can be an order of magnitude or more faster in a native build. For instance, I have some quarkus applications that can take 10 seconds to ready running via the jre that take 10ms or less to start as a graalvm built binary.
I wish JVM could at least recover the memory after some time and drop at runtime what quarkus / AOT drops at build time.
It can and already does. It mostly depends on the GC. Or do you mean non-heap memory that the runtime uses?
Depends on how much effort, like on C and C++, you are willing to put into PGO metadata for the compiler and linker.
Even if you can gather that PGO metadata a running application won't be able to adapt to changes in that data.
It works well enough for systems software written in C and C++, where Java still remains a niche option, even when it could deliver.