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Marco Realacci 2025-03-25 08:28:01 +01:00
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.obsidian/workspace.json vendored
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Concurrent Systems/notes/8 - Enhancing Liveness Properties.md
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Can we take the most basic protocol that satisfies the most basic liveness property (obstruction freedom) and "upgrade" it to bounded wait freedom? Can we take the most basic protocol that satisfies the most basic liveness property (obstruction freedom) and "upgrade" it to bounded wait freedom?
**Contention manager:** is an object that allows progress of processes by providing contention-free periods for completing their invocations. It provides 2 operations:
- `need_help(i)`: invoked by $p_i$ when it discovers that there is contention
- `stop_help(i)`: invoked by $p_{i}$ when it terminates its current invocation
**Enriched implementation:** when a process realizes that there is contention, it invokes need_help; when it completes its current operation, it invokes stop_help.
Why is it different from lock/unlock? Because this allows failures, and they can also happen in the contention-free period.