Java 10 - JIT Compiler

JEP 317 − Experimental Java-Based JIT Compiler

JIT compiler is written in C++ and is used to convert Java into Byte Code. Now Java 10 has option to enable an experimental Java based JIT compiler, Graal to be used instead of standard JIT compiler. Graal is using JVMCI, JVM Compiler Interface which was introduced in Java 9. Graal is available in Java 9 as well. With Java 10, we can enable Graal to test and debug the experimental JVM compiler.


java -XX:+UnlockExperimentalVMOptions -XX:+UseJVMCICompiler

Graal compiler is a complete rewrite of C++ based earlier compiler and is targeted for Linux/x64 based platform. Graal was introduced in Java 9 as an alternative of JIT compiler presently in use. Graal is a plugin to JVM and can be dynamically plugged in. It supports polyglot language interpretation as well.

Risks and Assumptions

As Graal is experimental and is subject to testing effort considering various Hotspots and jdk tests with various flag options. It may fail some benchmarks for performance as compared to standard JIT Ahead of Time compilers.

Kickstart Your Career

Get certified by completing the course

Get Started