JVM Comparison: Performance in 2023
| Runtime | License | Notable Features |
|---|---|---|
| OpenJDK | GPL + Classpath Exception | Reference implementation; broad ecosystem support. |
| Oracle JDK | Oracle No-Fee Terms for internal use | Commercial support, quarterly PSU patches, Flight Recorder/Mission Control. |
| Azul Platform Prime (Zulu/Prime) | Commercial | C4 pauseless GC, ReadyNow warmup profiles, tuned for low-latency workloads. |
| GraalVM Community/Enterprise | OSS + Commercial | High-performance JIT, polyglot support, Native Image AOT compilation. |
| IBM Semeru (Eclipse OpenJ9) | EPL | Low footprint JVM with balanced GC and shared classes cache. |
| SAP SapMachine | Apache 2.0 | Hardens OpenJDK with enterprise security patches and SAP tooling integration. |
Legacy runtimes such as JRockit and IKVM are no longer maintained; avoid them for new deployments.
Selecting a Runtime
- Support & Licensing: Determine whether you need vendor support (Oracle, Azul, IBM, Red Hat) or if community builds meet policy requirements.
- Workload Characteristics:
- Low-latency trading → look at Azul Prime or tuned OpenJDK builds with ZGC/Shenandoah.
- Memory-constrained containers → evaluate Eclipse OpenJ9 for smaller footprints.
- Polyglot or ahead-of-time needs → consider GraalVM for Native Image.
- Operational Tooling: Ensure observability pipelines (JFR, JMX, eBPF agents) are compatible with your chosen runtime.
- Benchmarking: Use JMH or production-like load tests; marketing benchmarks rarely match real workloads.
Upgrade & Maintenance Tips
- Stay on supported LTS lines (Java 17 or 21 as of 2024). Apply security patches on the quarterly cadence.
- Validate GC configuration during runtime upgrades; defaults change (e.g., G1 GC vs. ZGC availability).
- Monitor start-up warmup times if you rely on GraalVM Native Image; ahead-of-time builds trade startup for peak throughput.