Lecture "Operating system - Chapter 2: Processes and Threads" has contents: Processes, threads, interprocess communication, classical IPC problems, scheduling. Invite you to refer. | Processes and Threads Chapter 2 Processes Threads Interprocess communication Classical IPC problems Scheduling Processes The Process Model Multiprogramming of four programs Conceptual model of 4 independent, sequential processes Only one program active at any instant Process Creation Principal events that cause process creation System initialization Execution of a process creation system User request to create a new process Initiation of a batch job Process Termination Conditions which terminate processes Normal exit (voluntary) Error exit (voluntary) Fatal error (involuntary) Killed by another process (involuntary) Process Hierarchies Parent creates a child process, child processes can create its own process Forms a hierarchy UNIX calls this a "process group" Windows has no concept of process hierarchy all processes are created equal Process States (1) Possible process states running blocked ready Transitions between states shown Process . | Processes and Threads Chapter 2 Processes Threads Interprocess communication Classical IPC problems Scheduling Processes The Process Model Multiprogramming of four programs Conceptual model of 4 independent, sequential processes Only one program active at any instant Process Creation Principal events that cause process creation System initialization Execution of a process creation system User request to create a new process Initiation of a batch job Process Termination Conditions which terminate processes Normal exit (voluntary) Error exit (voluntary) Fatal error (involuntary) Killed by another process (involuntary) Process Hierarchies Parent creates a child process, child processes can create its own process Forms a hierarchy UNIX calls this a "process group" Windows has no concept of process hierarchy all processes are created equal Process States (1) Possible process states running blocked ready Transitions between states shown Process States (2) Lowest layer of process-structured OS handles interrupts, scheduling Above that layer are sequential processes Implementation of Processes (1) Fields of a process table entry Implementation of Processes (2) Skeleton of what lowest level of OS does when an interrupt occurs Threads The Thread Model (1) (a) Three processes each with one thread (b) One process with three threads The Thread Model (2) Items shared by all threads in a process Items private to each thread The Thread Model (3) Each thread has its own stack Thread Usage (1) A word processor with three threads Thread Usage (2) A multithreaded Web server Thread Usage (3) Rough outline of code for previous slide (a) Dispatcher thread (b) Worker thread Thread Usage (4) Three ways to construct a server Implementing Threads in User Space A user-level threads package Implementing Threads in the Kernel A threads package managed by the kernel Hybrid Implementations Multiplexing .
