7 - CPU Scheduling • Basic Concepts • Scheduling...

Info iconThis preview shows pages 1–9. Sign up to view the full content.

View Full Document Right Arrow Icon

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

View Full DocumentRight Arrow Icon

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

View Full DocumentRight Arrow Icon

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

View Full DocumentRight Arrow Icon

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

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

Unformatted text preview: CPU Scheduling • Basic Concepts • Scheduling Criteria • Scheduling Algorithms Basic Concepts • Maximum CPU utilization obtained with multiprogramming • CPU–I/O Burst Cycle – Process execution consists of a cycle of CPU execution and I/ O wait • CPU burst distribution Alternating Sequence of CPU And I/ O Bursts Histogram of CPU-burst Times CPU Scheduler • Selects from among the processes in memory that are ready to execute, and allocates the CPU to one of them • CPU scheduling decisions may take place when a process: 1. Switches from running to waiting state 2. Switches from running to ready state 3. Switches from waiting to ready 4. Terminates • Scheduling under 1 and 4 is nonpreemptive • All other scheduling is preemptive Dispatcher • Dispatcher module gives control of the CPU to the process selected by the short-term scheduler; this involves: – switching context – switching to user mode – jumping to the proper location in the user program to restart that program • Dispatch latency – time it takes for the dispatcher to stop one process and start another running Scheduling Criteria • CPU utilization – keep the CPU as busy as possible • Throughput – # of processes that complete their execution per time unit • Turnaround time – amount of time to execute a particular process • Waiting time – amount of time a process has been waiting in the ready queue • Response time – amount of time it takes from when a request was submitted until the first response is produced, not output (for time-sharing environment) Optimization Criteria • Max CPU utilization • Max throughput • Min turnaround time • Min waiting time • Min response time First-Come, First-Served (FCFS)...
View Full Document

This note was uploaded on 03/14/2010 for the course CSE SSZG516 taught by Professor Muralip during the Summer '10 term at Birla Institute of Technology & Science.

Page1 / 26

7 - CPU Scheduling • Basic Concepts • Scheduling...

This preview shows document pages 1 - 9. Sign up to view the full document.

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