{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

02_OS_Structures_2spp

02_OS_Structures_2spp - CSC 4103 Operating Systems Fall...

Info icon This preview shows pages 1–7. Sign up to view the full content.

View Full Document Right Arrow Icon
CSC 4103 - Operating Systems Fall 2009 Tevfik Ko ! ar Louisiana State University August 27 th , 2009 Lecture - II OS Structures Announcements TA Changed. New TA: Praveenkumar Kondikoppa Email: [email protected] All of you should be now in the class mailing list. Let me know if you haven’t received any messages yet. Lecture notes are available on the course web site. 2
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
3 Roadmap Major OS Components Corresponding OS Responsibilities OS Design and Implementation Different Design Approaches OS API System Calls Dual Mode of Operation 4 Computer System Organization Computer-system operation One or more CPUs, device controllers connect through common bus providing access to shared memory Concurrent execution of CPUs and devices competing for memory cycles
Image of page 2
5 Major OS Components ! Processes ! Memory management ! CPU Scheduling ! I/O Management 6 Processes " A process is the activity of executing a program Pasta for six boil 1 quart salty water stir in the pasta cook on medium until “al dente” – serve Program Process CPU input data thread of execution
Image of page 3

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

View Full Document Right Arrow Icon
7 Processes Pasta for six boil 1 quart salty water stir in the pasta cook on medium until “al dente” – serve " It can be interrupted to let the CPU execute a higher-priority process Program Process First aid – Get the first aid kit – Check pulse – Clean wound with alcohol – Apply band aid CPU (changes hat to “doctor”) input data thread of execution 8 Processes " . . . and then resumed exactly where the CPU left off Pasta for six boil 1 quart salty water stir in the pasta cook on medium until “al dente” – serve Program Process CPU (back to “chef”) input data thread of execution hmm... now where was I?
Image of page 4
9 Processes . . . . . . job 3 job 1 job 1 job 2 job 2 . . . . . . job 4 job 3 job 1 " Multitasking gives the illusion of parallel processing (independent virtual program counters) on one CPU (a) Multitasking from the CPU’s viewpoint Pseudoparallelism in multitasking job 2 job 2 job 3 job 3 job 1 job 1 job 1 job 4 (b) Multitasking from the processes’ viewpoint = 4 virtual program counters process 1 process 2 process 3 process 4 Processes 10 Timesharing is logical extension in which CPU switches jobs so frequently that users can interact with each job while it is running, creating interactive computing Response time should be < 1 second Each user has at least one program loaded in memory and executing ! process
Image of page 5

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

View Full Document Right Arrow Icon
11 Processes " Operating System Responsibilities: The O/S is responsible for managing processes # the O/S creates & deletes processes # the O/S suspends & resumes processes # the O/S provides mechanisms for process synchronization # the O/S provides mechanisms for interprocess communication # the O/S provides mechanisms for deadlock handling 12 Memory Management " Main memory The storage hierarchy " # large array of words or bytes, each with its own address # repository of quickly accessible data shared by the CPU and I/O devices # volatile storage that loses its contents in case of system failure
Image of page 6
Image of page 7
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