ch3_processes

Process

A program in execution that must progress in a sequential fashion without parallel execution of instructions.

Process Control Block (PCB)

A data structure that stores all the information about a process, including process state, program counter, CPU registers, and memory management information.

Process State

The state of a process can be New, Running, Waiting, Ready, or Terminated, each representing the status of the process during execution.

Context Switch

The process of saving the state of a currently running process and loading the state of the next process to be executed by the CPU.

Interprocess Communication (IPC)

Mechanisms provided by the operating system to allow processes to communicate with each other, using methods like shared memory and message passing.

Producer-Consumer Problem

A paradigmatic scenario where a producer process creates data that is consumed by a consumer process, often discussed in the context of synchronization.

Zombie Process

A terminated process that remains in the process table until its parent process clears it.

Orphan Process

A process that is left running in the system because its parent process has terminated.

Shared Memory

A mechanism allowing processes to communicate by accessing a common area of memory, requiring synchronization to manage concurrent access.

Message Passing

A method of IPC where processes communicate by sending and receiving messages without sharing memory.

Socket

An endpoint for communication defined by a combination of an IP address and a port number used in network communication.

Blocking Communication

A synchronous form of IPC where the sender is blocked until the message is received or the receiver is blocked until a message is available.

Non-blocking Communication

An asynchronous form of IPC where the sender sends a message and continues without waiting for the receiver, and the receiver can receive either a valid message or a null.

Cascading Termination

A situation where the termination of a parent process leads to the automatic termination of all its child processes.

Fork

A UNIX system call used to create a new process by duplicating the calling process.

exec

A UNIX system call used after a fork() to replace the process's current memory space with a new program.

wait()

A system call used by a parent process to wait for a child process to terminate.

Critical Section Problem

A situation where multiple processes or threads try to simultaneously access and modify shared resources, potentially leading to inconsistencies or deadlocks.

Deadlock

A state where two or more processes are unable to proceed because each is waiting for the other to release resources.

Starvation

A situation in which a process is perpetually denied the resources it needs to proceed, typically due to the scheduling policies.

Client-Server Communication

A model for structuring communications where a client sends requests to a server, which processes the request and sends a response.