GraalJS on OpenJDK with JVMCI - do I need to use Community Edition to get JVMCI functionaltiy ?

[kiwi1969]

I am confused about the actual differences between the GraalJS Enterprise and the Community Edition, and how they relate to my situation, as described below.

I am developing an application on the Z/OS platform, where GraalVM does not exist, so am forced to use IBMJDK (which is a patched version of OpenJDK using OpenJ9).
I patched the code I pulled from GitHub, to not outright fail on Z/OS due to "Unsupported Platform", and I see that GraalJS seems to run fine on both MacOS and Z/OS
I am unsure whether I built for Community or for Enterprise (I just did the default builds without special options), but think I possibly built for community, as there is no jar with "enterprise" in the name.

What I have seems to work fine, bit I see that JVMCI only works for me on MacOS, when using GraalVM runtime, and runs without JVMCI when on OpenJDK runtime.
I was assuming anyhow that on OpenJDK the JVMCI would not work for me, as seemed to be a feature of GraalVM.

Also on Z/OS, I have no libraries compiled, so it falls back to interpreter anyhow. Also OpenJ9 doesn't support the JVMCI optimization that Hotspot uses, so we are stuck with OpenJ9 AOT compilation and caches here.

But then I saw JEP 243 to allow compilers on OpenJDK
So, ignoring Z/OS and OpenJ9, does GraalJS actually support JVMCI on OpenJDK, and if so, do I then have to use the Community Edition of GraalJS ?

Even if OpenJDK doesn't support the JVMCI functionalty, should I still be using Community Edition (considering Enterprise seems to add no additional value to OpenJDK users)?

[fniephaus]

Hi @kiwi1969,
Thanks for reaching out.

I see that GraalJS seems to run fine on both MacOS and Z/OS

Cool! I assume it runs on OpenJ9?

I am unsure whether I built for Community or for Enterprise (I just did the default builds without special options), but think I possibly built for community, as there is no jar with "enterprise" in the name.

The only difference between the js and the js-community artifacts is that js currently also pulls in truffle-enterprise, which provides additional features (e.g., sandboxing or auxiliary engine caching). If you don't need them, you can use js-community. BTW: In the upcoming 25 release, we plan to change this and make the additional Truffle features optional. So this means js and js-community will essentially be identical (also in terms of the license) at which point we will likely deprecate js-community to simplify everything for the users.

I was assuming anyhow that on OpenJDK the JVMCI would not work for me, as seemed to be a feature of GraalVM.

JVMCI is an OpenJDK feature. In fact, we are about to improve our docs and explain how to enable Runtime Compilation on OpenJDK.

Also on Z/OS, I have no libraries compiled, so it falls back to interpreter anyhow. Also OpenJ9 doesn't support the JVMCI optimization that Hotspot uses, so we are stuck with OpenJ9 AOT compilation and caches here.

Correct. Even though OpenJ9 does not support JVMCI, GraalJS still works but it is not runtime-optimized by the Graal compiler. So you essentially only get GraalJS interpreter performance, which may very well be good enough for your use cases.

So, ignoring Z/OS and OpenJ9, does GraalJS actually support JVMCI on OpenJDK, and if so, do I then have to use the Community Edition of GraalJS ?

GraalVM CE, Oracle GraalVM, Oracle JDK, and OpenJDK all support JVMCI so GraalJS can be runtime-optimized on these runtimes. You can use GraalVM CE, but can also can use an OpenJDK build. For best performance, you can also use Oracle GraalVM which performs additional compiler optimizations.

Even if OpenJDK doesn't support the JVMCI functionalty, should I still be using Community Edition (considering Enterprise seems to add no additional value to OpenJDK users)?

GraalVM CE doesn't need additional flags to enable runtime compilation compared with OpenJDK. It also ships libgraal (the native image version of Graal) which is slightly faster than jargraal (the JAR version of Graal).
BTW: Oracle GraalVM is the successor of GraalVM Enterprise Edition. Unlike GraalVM EE, Oracle GraalVM is released under a permissive license (see https://blogs.oracle.com/java/post/graalvm-free-license). As the GraalVM download page states, "Oracle GraalVM is free to use in production and free to redistribute, at no cost, under the GraalVM Free Terms and Conditions".

Hope this helps!

-- Fabio