Module 5.1.3 - Peterson's Solution

Flashcards covering the technical implementation, variables, and pros/cons of Peterson's solution as described in the lecture notes.

Peterson's solution

A software-based solution to the critical section problem that allows two processes to share a resource without conflict.

$$FALSE$$

A constant defined as $0$ used to indicate that a process is not interested in entering a critical region.

$$TRUE$$

A constant defined as $1$ used to indicate that a process is interested in entering a critical region.

$$N$$

A constant defined as $2$, representing the number of processes in the implementation.

$$turn$$

A global variable that tracks whose turn it is to enter the critical region.

$$interested[N]$$

An array where all values are initially set to $0$ ($FALSE$), used to track which processes want to enter the critical region.

$$enter\_region(int\,process)$$

A function where a process signals interest by setting $interested[process] = TRUE$, sets the $turn$ to itself, and enters a while loop to wait if the other process is also interested and it is currently its turn.

$$other$$

A local variable calculated as $1 - process$ to determine the ID of the opposite process.

$$leave\_region(int\,process)$$

A function where a process indicates its departure from the critical region by setting its entry in the $interested$ array to $FALSE$.

Busy waiting

A disadvantage (con) of Peterson's solution where a process continuously executes a null statement in a while loop while waiting for access to the critical region.

No strict alternation

An advantage (pro) of Peterson's solution, meaning processes are not required to enter the critical region in a fixed, alternating order if only one process is interested.