Transactional memory

on YouTube ↗01h 13m

" summary

Overview of transactional memory, showing concrete mechanisms and limits: hardware uses cache coherence with extra bits to implement Intel TSX via _XBEGIN/_XABORT, aborting on cache overflow, page faults or interrupts; software uses retry/orElse for conditional waits and composition; practical pattern is hybrid lock elision (speculative transaction then fallback to locks) to accelerate legacy code; a novel technique called lock teleportation moves locks inside a transaction to traverse lists faster. Notes which failures are fatal, when to retry, and that small transactions perform best.

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" chapters (25)

1. 0:00Start
2. 2:29Shared Memory Multiprocessors
3. 3:46Free Ride of Software
4. 5:54Amdahl's Law
5. 8:23The Meaning of Amdahl's Law
6. 15:04Advantage of Coarse Brain Locks
7. 17:48Locking Relies on Conventions
8. 18:54Comment from the Linux Kernel
9. 26:22Monitor Weight and Signal
10. 26:55The Monitor Weight and Signal Problem
11. 28:47The Transactional Manifesto
12. 29:14Atomic Transactions
13. 34:04Trivial Examples of Atomic Blocks
14. 38:16Problems with False Conflicts
15. 39:59Conditional Weighting
16. 40:51Dangers and Pitfalls with Monitor Weights
17. 42:08How To Implement Atomic Transactions inside Inside Programming Languages
18. 42:51Hardware Transactional Memory
19. 44:02Insight into the Hardware Transactional Memory
20. 44:35Standard Cash Coherence
21. 53:01Locked Teleportation
22. 57:57Memory Management
23. 59:27Effect on Energy on Architecture
24. 1:00:50Data Structures
25. 1:01:40Hype Curve

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