Chapter 7: Deadlocks
Operating System Concepts – 9th Edition Silberschatz, Galvin and Gagne ©2013
, Chapter 7: Deadlocks
● System Model
● Deadlock Characterization
● Methods for Handling Deadlocks
● Deadlock Prevention
● Deadlock Avoidance
● Deadlock Detection
● Recovery from Deadlock
Operating System Concepts – 9th Edition 7.2 Silberschatz, Galvin and Gagne ©2013
, Chapter Objectives
● To develop a description of deadlocks, which prevent
sets of concurrent processes from completing their
tasks
● To present a number of different methods for
preventing or avoiding deadlocks in a computer
system
Operating System Concepts – 9th Edition 7.3 Silberschatz, Galvin and Gagne ©2013
, System Model
● System consists of resources
● Resource types R1, R2, . . ., Rm
CPU cycles, memory space, I/O devices
● Each resource type Ri has Wi instances.
● Each process utilizes a resource as follows:
● request
● use
● release
Operating System Concepts – 9th Edition 7.4 Silberschatz, Galvin and Gagne ©2013
Operating System Concepts – 9th Edition Silberschatz, Galvin and Gagne ©2013
, Chapter 7: Deadlocks
● System Model
● Deadlock Characterization
● Methods for Handling Deadlocks
● Deadlock Prevention
● Deadlock Avoidance
● Deadlock Detection
● Recovery from Deadlock
Operating System Concepts – 9th Edition 7.2 Silberschatz, Galvin and Gagne ©2013
, Chapter Objectives
● To develop a description of deadlocks, which prevent
sets of concurrent processes from completing their
tasks
● To present a number of different methods for
preventing or avoiding deadlocks in a computer
system
Operating System Concepts – 9th Edition 7.3 Silberschatz, Galvin and Gagne ©2013
, System Model
● System consists of resources
● Resource types R1, R2, . . ., Rm
CPU cycles, memory space, I/O devices
● Each resource type Ri has Wi instances.
● Each process utilizes a resource as follows:
● request
● use
● release
Operating System Concepts – 9th Edition 7.4 Silberschatz, Galvin and Gagne ©2013
