Project Loom

on YouTube ↗36m

" summary

Prototype opens sources continuations and fibers (tail calls not started) and implements continuations and fibers in Java, scheduling fiber tasks on fork/join carrier threads with a demo swapping Jetty threads for fibers: 5,000 rps load shows threads dropping ~45–50% of requests while fibers handle the load with no dropped requests. Continuations copy native stack into two heap arrays and use a lazy copy thawing optimization. Current limits: native frames, synchronized blocks pin carrier threads, thread API and thread‑local semantics are provisional; fiber footprint is bytes to low kilobytes vs ~1 MB per kernel thread.

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" chapters (18)

1. 0:00Start
2. 0:03Ron Pressler
3. 0:39Project Loom
4. 2:19Continuations
5. 4:53Fibers
6. 5:49Why Fibers
7. 7:20Scheduler
8. 7:50Continuation Api
9. 8:15Java Lang Fiber
10. 8:44Wrapping a User's Task in the Continuation
11. 9:10Fiber Tasks
12. 18:22Latency
13. 20:26Limitations
14. 21:31Synchronized Blocks
15. 25:10Footprint
16. 28:32Requirements
17. 29:14Continuation Stacks
18. 32:51Lazy Copy

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