Can indefinite blocking take place, Operating System

Consider the subsequent resource-allocation policy. Requests as well as releases for resources are allowed at any time. If a request for resources can't be satisfied because the resources aren't available then we check any processes that are blocked waiting for resources. If they have the desired resources after that these resources are taken away from them and are given to the requesting process. The vector of the resources for which the process is waiting is increased to include the resources that were taken away. For instance consider a system with three resource types and the vector Available initialized to (4,2,2). If process P0 asks for (2, 2, 1) it gets them. If P1 asks for (1,0,1) it gets them. After that if P0 asks for (0, 0, 1), it is blocked (resource not available). If P2 now asks for (2, 0, 0) it gets the available one (1,0,0) in addition to one that was allocated to P0 (since P0 is blocked). P0's Allocation vector goes down to (1, 2, 1) and its Need vector goes up to (1, 0, 1).

a. Can deadlock take place? If you answer "yes" give an instance and If you answer "no," specify which necessary condition cannot occur.

b. Can indefinite blocking take place? Describe your answer.

Answer:

a. Deadlock cannot take place because pre-emption exists.

b. Yes A process may never obtain all the resources it needs if they are continuously pre-empted by a series of requests such as those of process C.

Posted Date: 7/27/2013 5:04:08 AM | Location : United States







Related Discussions:- Can indefinite blocking take place, Assignment Help, Ask Question on Can indefinite blocking take place, Get Answer, Expert's Help, Can indefinite blocking take place Discussions

Write discussion on Can indefinite blocking take place
Your posts are moderated
Related Questions
Q. Operating System as User Interface? • Every general purpose computer comprises the operating system, hardware, system programs and application programs. The hardware compris

Define properties of Real time operating system Real time :- Often used in a dedicated application, this system reads information from sensors and must respond within a fixed a


A daemon is a process that removes itself from the terminal and disconnected, executes, in the background, waiting for requests and responding to them. It may also be described as

What is an effector process? The effector process is a method that verifies itself.The effector process exists in particular criteria.

Conservative GC can be used for languages such as C and C++, which were not explicitly designed for garbage collection. This is a non-copying technique. A conservative garbage coll

What are batch systems? Batch systems are quite appropriate for implementing large jobs that need little interaction. The user can submit jobs and return later for the results.

Q. In following Section we mentioned that disabling interrupts frequently could affect the system's clock. Describe why it could and how such effects could be minimized.

How are file sharing and protection implemented? To implement file protection and sharing, the system ought to maintain more file and directory attributes than are needed on a

What are the benefits of thread pools:- The benefits of thread pools are 1. It is usually faster to service a request with an existing thread than waiting to make a thread.