What the CRaC Superfast JVM startup

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" summary

CRaC (Coordinated Restore at Checkpoint) uses a patched OpenJDK (demo build jdk 17.0.2) plus CRIU to snapshot a warmed JVM to disk and restore it later; startup on Linux x64 containers falls from seconds to ~30–50 milliseconds in the demos. The project adds a checkpoint/restore API (Resource with beforeCheckpoint and afterRestore), a global context for registration and reversed teardown order, and CLI flags to write/restore snapshots; checkpoints shut down the JVM, require handling time‑dependent state, and are CPU‑architecture sensitive.

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" chapters (13)

1. 0:00Start
2. 5:17LEVELS OF EXECUTION
3. 6:23EXECUTION CYCLE
4. 7:10DEOPTIMISATION
5. 9:06JVM STARTUP
6. 11:00JVM PERFORMANCE GRAPH
7. 16:52AOT VS JIT
8. 21:40CRIU CHALLENGES
9. 30:31SIMPLE EXAMPLE
10. 38:01CREATING A CHECKPOINT
11. 40:26COMPATIBILITY...
12. 44:42SUMMARY...
13. 45:16INFRASTRUCTURE COST

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