Operating Systems: Processes, PCB, and Process Synchronization

Flashcards covering essential operating systems concepts including processes, the Process Control Block (PCB), registers, cooperative processes, race conditions, and critical-section requirements.

Process

An active program currently executing in main memory (RAM) that utilizes CPU time and resources, possesses a process state, and is represented by a Process Control Block (PCB).

Process Control Block (PCB)

A structure (also called a task control block) maintained by the Operating System for every process that stores key execution details including process state, process ID (PID), program counter, CPU registers, scheduling information, memory details, and I/O status.

Stack Pointer

A CPU register that points to the top of the stack, indicating where temporary data such as function calls, parameters, and return addresses are currently stored.

Base Address

A memory-related term representing the starting address of a process in main memory (RAM).

Cooperative Process

A process that shares common resources, memory, variables, code, or buffers with other processes, meaning its execution can affect or be affected by other processes.

Race Condition

A problem that occurs when multiple processes access and modify shared data simultaneously, causing the final result to depend on execution timing and potentially yielding incorrect output.

Critical Section

The specific portion of a program where shared variables, memory, or resources are accessed and modified by a process.

Mutual Exclusion

A critical-section requirement ensuring that if a process is executing in its critical section, no other process can enter its critical section at the same time.

Progress

A critical-section requirement specifying that if no process is in its critical section and some processes wish to enter, only those not executing in their remainder section can participate in deciding which enters next, and that decision cannot be delayed indefinitely.

Bounded Waiting

A requirement ensuring there is a limit on the number of times other processes can enter their critical section after a process has requested entry, preventing process starvation.