Pardon the Interruption: Loop Preemption in Go 1.14
summary
Go 1.14 adds asynchronous preemption that uses signals (SIGURG) to stop goroutines anywhere and performs conservative innermost frame scanning to find pointers without full stack maps. It reduces preemption delay to ~25 microseconds, adds about 0.3% binary metadata, and has zero steady-state overhead. The implementation avoids per-loop checks, fixes tight-loop 47x throughput stalls and scheduler deadlocks, and works across architectures after kernel and debugger interactions are handled.
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chapters (6)
- 0:00Start
- 7:29Preempt back-edges, like other languages
- 9:08"Forward simulation" like some languages
- 11:11Use interrupts, like an OS kernel
- 13:22Signals + GC stack maps at every instruction
- 21:01Debug the Linux kernel?!
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