PPT-Chapter 7, Deadlocks 1 7.1 System Model

In order to talk about deadlocks in a system its helpful to have a model of the system A system consists of a set of resources The resources can be grouped into types Processes compete to have unique access to instances of the types. icssaitamauacjp Abstract This article presents some examples of tasking deadlocks concerning tasking synchronization waiting relations de57519ned in Ada 95s RealTime Systems Annex 1 Introduction A tasking deadlock in a concurrent Ada program is a sit 1 List three examples of deadlocks that are not related to a computer system environment Answer Two cars crossing a singlelane bridge from opposite directions A person going down a ladder while another person is climbing up the ladder Two trains 1 List three examples of deadlocks that are not related to a computer system environment Answer Two cars crossing a singlelane bridge from opposite directions A person going down a ladder while another person is climbing up the ladder Two trains tr Detection and Avoidance. Prof. Sirer. CS 4410. Cornell University. System Model. There are non-shared computer resources. Maybe more than one instance. Printers, Semaphores, Tape drives, CPU. Processes need access to these resources. 1. 6. Deadlocks. 6.1 Deadlocks with Reusable and Consumable. . Resources. 6.2 Approaches to the Deadlock Problem . 6.3 A System Model . Resource Graphs . State Transitions. Deadlock States and Safe States . Tore Larsen. With slides from . T. Plagemann, C. . . Griwodz. , K. Li,. A. . Tanenbaum. and M. van Steen. Resources. Resource allocation is a central OS concern. Examples . of computer resources. CPU. Spring 2013. Deadlocks. Dan Tsafrir (13/5/2013). Partially based on slides by Hagit Attiya. OS (234123) - spring 2013 - deadlocks. 1. Text @ OS notes book. Much of the material appears in Section 3.2 in Feitelson’s OS notes book. Deadlocks – Problems and Solutions. CS. . 111. Operating . Systems . Peter Reiher. . Outline. The deadlock problem. Approaches to handling the problem. Handling general synchronization bugs. Simplifying synchronization. 1. 7.1 System Model. A system consists of a set of resources. The resources can be grouped into types. Processes compete to have (unique) access to instances of the types. 2. Examples of resource types:. Deadlock . detection. Resource Allocation Graphs. Resource Pool and . C. ounting Semaphores. Dining . Philosophers Problem. Condition Variables . Resource Tables. Deadlock Definition. A . deadlock.  is a situation in which two or more competing actions are each waiting for the other to finish, and thus neither ever does. David Ferry, Chris Gill. CSE . 422S . - . Operating Systems Organization. Washington University in St. Louis. St. Louis, MO 63143. 1. Linux is a Preemptive Kernel. In Linux, many activities may execute concurrently across. Spring 2013. Deadlocks. Dan Tsafrir (13/5/2013). Partially based on slides by Hagit Attiya. OS (234123) - spring 2013 - deadlocks. 1. Text @ OS notes book. Much of the material appears in Section 3.2 in Feitelson’s OS notes book. OPERATING SYSTEMS . DEADLOCKS. 7: Deadlocks. 2. What Is In This Chapter?. What is a deadlock?. Staying Safe: Preventing and Avoiding Deadlocks. Living Dangerously: Let the deadlock happen, then detect it and recover from it.. Chapter 7: Deadlocks Chapter 7: Deadlocks The Deadlock Problem System Model Deadlock Characterization Methods for Handling Deadlocks Deadlock Prevention Deadlock Avoidance Deadlock Detection Recovery from Deadlock