CS307 Operating Systems
Introduction
Fan Wu
Department of Computer Science and Engineering
Shanghai Jiao Tong University
Spring 2013
Operating Systems
Operating Systems
2
Operating Systems
UNIX-family: BSD(Berkeley Software Distribution), System-V, AIX,
CS307 OperatingSystemExercises Spring2013
Exercise3:MemoryManagement
Duedate:Apr.11,2011
1.
2.
3.
A machine has 48bit virtual addresses and 32bit physical addresses. Each page size is 16K
Bytes.Eachtableentrytakes4Bytes.Howmuchmemoryisneededtoholdthepaget
Exercise 2 Solution
1.
a) Variable:
int countEast=countWest=0;
/number of waiting baboons on each direction
b) Semaphore:
Semaphore eastWard=westWard=mutexEast=mutexWest=mutex=1,ropeWest=ropeEast=N;
c)
#EastWard:
wait(mutex);
wait(westWard);
wait(mutexEas
CS307 OperatingSystemExercises Fall2011
Exercise2:ProcessSynchronization&Deadlocks
Duedate:Apr.4,2011
1.
(Baboons Crossing Problem) A canyon cuts through the territory of a colony of baboons.
The baboons use a rope stretching across the canyon to cross f
CS307 OperatingSystemExercises Spring2013
Exercise1:CPUScheduling
Duedate:BeforeClass,March19,2013
1.
Consider the following set of processes, with the arrival times and the length of the
CPUburst times given in milliseconds, and the priorities given so t
CS307 Operating Systems
Distributed-File Systems
Guihai Chen
Department of Computer Science and Engineering
Shanghai Jiao Tong University
Spring 2013
Background
Distributed file system (DFS) a distributed implementation of the
classical time-sharing mode
CS307 Operating Systems
Distributed System Structures
Guihai Chen
Department of Computer Science and Engineering
Shanghai Jiao Tong University
Spring 2013
Motivation
Distributed system is collection of loosely coupled processors
interconnected by a commu
CS307 Operating Systems
File-System
Fan Wu
Department of Computer Science and Engineering
Shanghai Jiao Tong University
Spring 2013
File Concept
A file is an abstraction of logical address space
A file is a named collection of related information that i
CS307 Operating Systems
Mass-Storage Systems
Fan Wu
Department of Computer Science and Engineering
Shanghai Jiao Tong University
Spring 2013
The First Commercial Disk Drive
1956
IBM RAMDAC computer
included the IBM Model
350 disk storage system
5M (7 bit)
CS307 Operating Systems
Virtual Memory
Fan Wu
Department of Computer Science and Engineering
Shanghai Jiao Tong University
Spring 2013
Background
Code needs to be in memory to execute, but entire program rarely used
Error code, unusual routines, large da
CS307 Operating Systems
Main Memory
Fan Wu
Department of Computer Science and Engineering
Shanghai Jiao Tong University
Spring 2013
Background
Program must be brought (from disk) into memory and placed within a
process for it to be run
Main memory and r
CS307 Operating Systems
Deadlocks
Fan Wu
Department of Computer Science and Engineering
Shanghai Jiao Tong University
Spring 2013
Bridge Crossing Example
Traffic only in one direction
Each section of a bridge can be viewed as a resource
A deadlock occu
CS307 Operating Systems
Process Synchronization
Fan Wu
Department of Computer Science and Engineering
Shanghai Jiao Tong University
Spring 2013
Background
Concurrent access to shared data may result in data inconsistency
Maintaining data consistency req
CS307 Operating Systems
CPU Scheduling
Fan Wu
Department of Computer Science and Engineering
Shanghai Jiao Tong University
Spring 2013
Basic Concepts
Maximize CPU utilization obtained with multiprogramming
CPUI/O Burst Cycle Process execution consists o
CS307 Operating Systems
Threads
Fan Wu
Department of Computer Science and Engineering
Shanghai Jiao Tong University
Spring 2013
What is a thread?
A thread is a basic unit of CPU utilization
contains a thread ID, a program counter, a register set, and a s
CS307 Operating Systems
Processes
Fan Wu
Department of Computer Science and Engineering
Shanghai Jiao Tong University
Spring 2013
Process Concept
An operating system executes a variety of programs:
Batch system jobs
Time-shared systems user programs or
CS307 Operating Systems
Operating-System Structures
Fan Wu
Department of Computer Science and Engineering
Shanghai Jiao Tong University
Spring 2013
Operating System Services Structure
Operating systems provide an environment for execution of
programs and
Exercise 3 Solution
1.
1) We assume that one word only holds one byte, then we can get the page size: 214 B.
And the number of the pages is 248/214=234.
Each table entry takes 4 Bytes. Then we can get the memory needed:
234*4B=236B=64GB
2) When one word h
