Full Speed Ahead! Ahead of Time Compilation for Java SE

on YouTube ↗50m

" summary

JDK 9 adds experimental ahead‑of‑time compilation that uses jaotc to produce an ELF shared library (uses Graal as the compiler), improving startup and warmup by loading machine code instead of JITing. Compiling java.base often needs ~5–6 GB heap and 20–30 minutes; generated code is roughly ~10% slower than C2 but supports compile-for-tiered so C2 can later recompile. Only Linux amd64 with libelf is supported; GC mode and compressed‑oops must match, and invokedynamic/custom class loaders aren’t supported.

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" chapters (8)

1. 0:00Introduction to AOT
2. 3:50The JVM execution model
3. 11:47AOT technical benefits
4. 16:18Contextualizing AOT features
5. 22:03Practical AOT implementation
6. 30:18Verification and dependencies
7. 38:33Advanced GC and memory details
8. 48:25Conclusion and resources

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