A stop-the-world debugger for Erlang (and the BEAM)

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" summary

edb extends OTP with a new debugging API and a compiler flag that emits beam debug info so the VM can install per-line trampolines (run-time jumps) and create stack frames on the fly; a debugger node injects support modules over distribution and suspends nearly all user processes while preserving timers to give an illusion of a stopped VM. Stepping is simulated by conditional breakpoints; running two and a half days of real WhatsApp tests shows overhead is acceptable. Available on GitHub and integrated into VS Code via the Erlang Language Platform.

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" chapters (15)

1. 0:00Debugging challenges in Erlang
2. 3:38Traditional debugger limits
3. 5:30Stop-the-world debugger design
4. 7:39Debugger system architecture
5. 9:45VM changes for breakpoints
6. 13:27Debugger primitives
7. 14:33Suspending processes
8. 16:41Timers during suspension
9. 18:26Inspecting variables
10. 20:18Stepping without VM changes
11. 24:37Debugging performance impact
12. 26:50Testing and adoption
13. 27:10Debugger shortcuts
14. 31:44Future improvements
15. 32:06Debugger availability