Building Robust Inter-Process Queues in C++

on YouTube ↗01h 07m

" summary

Examines two popular SPSC queues (Daugaard, Rigtorp) and shows that simply mmap-ing them breaks: std::atomic is not an implicit-lifetime type in C++20, placement-newed objects and internal pointers require explicit reinitialization, and user-defined constructors make shared-memory instances undefined. Proposes a separated design: a metadata-backed queue that enforces single-producer/single-consumer ownership, reattach reader/writer pointers on process attach, and a robust process lock using PID+start-time plus an optional MCAST special-consumer for non-blocking broadcasts.

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" chapters (10)

1. 0:00Introduction
2. 5:01Inter-process queues requirements
3. 10:27Dow Guard ring buffer
4. 21:44Cross-process queue challenges
5. 33:36Undefined behavior in queues
6. 44:12C++20 lifetime types
7. 52:39Cache line alignment
8. 54:07Separation of concerns
9. 1:01:17MCAST queues production
10. 1:06:15Q&A

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