vault backup: 2025-03-10 23:08:12

This commit is contained in:
Marco Realacci 2025-03-10 23:08:12 +01:00
parent 67f0545b57
commit b5aab42150

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@ -94,7 +94,10 @@ lock(i) :=
- $p_n$ invokes lock alone, completes its CS and its new DATE is n
- all other $p_i, i \in P$ (with P being the set of all processes) will have `DATE[i] < n`, as their value for DATE is decreased
- suppose every process invoke lock, then $p_n$ has to wait all other processes to complete their CSs
- scenario 1: every process keeps
- *scenario 1*: every other $p_i$ keep invoking lock again immediately after the unlock
- `DATE[i]` will always be $> DATE[n]$
- after $n-1$ turns, `DATE[n]` will have `DATE[n] = 1`, with every other `DATE[i] > 1, i!=n` -> ️✅
- *scenario 2*: not every process invokes the lock
**Lemma 1:** Suppose we have $n$ processes, then $\not \exists p_{j} : DATE[j]=DATE[i] \forall i \in [0, n]$ (non esistono due processi con lo stesso valore per DATE)
*Proof:*