OS_ch03_F07 - I.-C. Lin, Assistant Professor. Textbook:...

Info iconThis preview shows pages 1–16. Sign up to view the full content.

View Full Document Right Arrow Icon
I.-C. Lin, Assistant Professor. Textbook: Operating System Principles 7ed HAPTER 3: PROCESSES ONCEPT CHAPTER 3: PROCESSES-CONCEPT
Background image of page 1

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

View Full DocumentRight Arrow Icon
hapter 3: Processes oncept Chapter 3: Processes-Concept ± Overview ± Process Scheduling ± Operations on Processes t C i t i ± Interprocess Communication ± Examples of IPC Systems ± Communication in Client-Server Systems
Background image of page 2
rocess Concept Process Concept n operating system executes a variety of programs ± An operating system executes a variety of programs: ± Batch system jobs ± Time-shared systems user programs or tasks ± Textbook uses the terms job and process almost interchangeably ± Process a program in execution; process execution must progress in sequential fashion ± A process includes: ± program counter ack ± stack ± data section ± ……
Background image of page 3

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

View Full DocumentRight Arrow Icon
rocess in Memory Process in Memory
Background image of page 4
rocess State Process State ± As a process executes, it changes state ± new : The process is being created ± running : Instructions are being executed ± waiting : The process is waiting for some event to occur ady The process is waiting to be assigned to a process ± ready : ± terminated : The process has finished execution
Background image of page 5

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

View Full DocumentRight Arrow Icon
iagram of Process State Diagram of Process State
Background image of page 6
rocess Control Block (PCB) Process Control Block (PCB) Information associated with each process ± Process state ± Program counter ± CPU registers ± CPU scheduling information ± Memory-management information ± Accounting information ± I/O status information /
Background image of page 7

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

View Full DocumentRight Arrow Icon
rocess Control Block (PCB) Process Control Block (PCB)
Background image of page 8
PU Switch From Process to Process CPU Switch From Process to Process
Background image of page 9

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

View Full DocumentRight Arrow Icon
rocess Scheduling Queues Process Scheduling Queues b e e t f ll i th t ± Job queue set of all processes in the system ± Ready queue set of all processes residing in main memory, ready and waiting to execute ± Device queues set of processes waiting for an I/O device ± Processes migrate among the various queues
Background image of page 10
Ready Queue And Various I/O Device Queues
Background image of page 11

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

View Full DocumentRight Arrow Icon
presentation of Process Scheduling Representation of Process Scheduling
Background image of page 12
chedulers Schedulers ng rm scheduler r job scheduler) ± Long-term scheduler (or job scheduler) ± selects which processes should be brought into the ready queue ort- rm scheduler r CPU scheduler) ± Short term scheduler (or CPU scheduler) ± selects which process should be executed next and allocates CPU
Background image of page 13

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

View Full DocumentRight Arrow Icon
ddition of Medium Term Scheduling Addition of Medium Term Scheduling
Background image of page 14
chedulers (Cont.) Schedulers (Cont.) hort rm scheduler is invoked very frequently (milliseconds) ± Short-term scheduler is invoked very frequently (milliseconds) (must be fast) ± Long-term scheduler is invoked very infrequently (seconds, minutes) (may be slow) ± The long-term scheduler controls the degree of multiprogramming ± Processes can be described as either: ± I/O-bound process spends more time doing I/O than computations, many short CPU bursts ± CPU-bound process spends more time doing computations; few very long CPU bursts
Background image of page 15

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

View Full DocumentRight Arrow Icon
Image of page 16
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 44

OS_ch03_F07 - I.-C. Lin, Assistant Professor. Textbook:...

This preview shows document pages 1 - 16. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online