Computer Science Chapter 6: Synchronization Tools

A situation where multiple processes try to access and modify shared data concurrently, leading to unpredictable and potentially incorrect results.

A set of instructions that must be executed atomically, meaning that either all instructions complete successfully or none of them do. It guarantees that if a process is interrupted while executing the critical section, the data will be left in a consistent state.

A method used to protect shared resources from simultaneous access by multiple processes. It ensures mutual exclusion, guaranteeing that a process can only access a resource if it is not currently being used by another process.

A mechanism that allows processes to communicate and coordinate their actions safely, ensuring data consistency and preventing race conditions.

A technique used to guarantee that changes to shared memory made by one processor are visible to other processors. Memory barriers ensure that the order of memory operations is maintained, preventing race conditions and ensuring data consistency.

The problem of designing a protocol to ensure that only one process can access the shared resource (critical section) at a time, preventing data corruption due to simultaneous access.

A set of rules or mechanisms that govern access to shared resources, ensuring that only one process can access the critical section at any given time. These rules are crucial to protect data integrity and prevent race conditions.

A requirement for any solution to the critical section problem. It ensures that at any given time, only one process can be executing its critical section, preventing multiple processes from accessing and modifying shared data simultaneously. Imagine a one-lane tunnel where only one car can pass at a time, avoiding head-on collisions.

Ensures that a process doesn't wait forever to enter its critical section. There's a limit on how many times other processes can enter their critical sections after a process requests entry.

This method disables interrupts during the critical section, preventing other processes from interrupting and causing data inconsistency. It's not ideal for longer critical sections.

This solution aims to prevent race conditions in a two-process scenario. Atomic instructions like load and store are used, and a shared variable turn determines who gets to enter the critical section.

The process waits until it's its turn to enter the critical section, indicated by the turn variable. It then sets turn to the other process' number, allowing the other process to enter the critical section.

This process waits for its turn based on the turn variable. After entering the critical section, it sets turn to the other process' number, giving them access.

This requirement ensures that all processes eventually get a chance to enter their critical sections. The solution should prevent any process from being continuously blocked.

It refers to the situation where a process is continuously denied access to the critical section while other processes are allowed entry. This can happen despite the mutual exclusion and bounded waiting being satisfied.

This situation arises when there are multiple CPUs. Interrupts can be disabled on one CPU, but the critical section code might be executing on another CPU, leading to potential violations of mutual exclusion.