{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

Lecture9-intro-to-processes-part1

Lecture9-intro-to-processes-part1 - Announcements CS 3214...

Info icon This preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
1 CS 3214 Computer Systems Godmar Back Lecture 9 Announcements Exercise 4 will be posted today Project 3 coming CS 3214 Fall 2011 THREADS AND PROCESSES Part 1 CS 3214 Fall 2011 Processes Def: An instance of a program in execution OS provides each process with key abstractions – Logical control flow 1 flow – single-threaded process Multiple flows – multi-threaded process – Private address space – Abstracted resources: e.g., stdout/stdin file descriptors These abstractions create the illusion that each process has access to its own – CPU (or CPUs for multi-threaded processes) – Memory – Devices: e.g., terminal CS 3214 Fall 2011 Context Switching Historical motivation for processes was introduction of multi-programming: – Load multiple processes into memory, and switch to another process if current process is (momentarily) blocked This required protection and isolation between these This required protection and isolation between these processes , implemented by a privileged kernel: dual- mode operation. Time-sharing: switch to another process periodically to make sure all processes make equal progress Switch between processes is called a context switch CS 3214 Fall 2011 Dual-Mode Operation
Image of page 1

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Image of page 2
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern