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
Explain the Thread Local Storage (TLS)    Windows NT provides unique functions for per-thread data management. Thread local storage (TLS) is a concept defined in NT so develope

Define semaphore A semaphore is a protected abstract or variable data type that constitutes the classic method for restricting access to shared resources like shared memory in

Basic File System Uses the specific device driver. Deals with blocks of data that are exchanged with the physical device. Concerned with the placement of blocks on

Relative file organization A relative file is an array of fixed-length slots and the records can be inserted in the first free slot found from the beginning of the file and


Q. Consider a file at present consisting of 100 blocks. Presume that the file control block (and the index block in the case of indexed allocation) is already in memory. Compute h

explain the link between operations management and strategic planning of daily goods shop


Ask question Project Details PROJECT OVERVIEW The ABC Hospital is upgrading their version of Windows. As part of the upgrade, 100 new computers will be purchased. Your task is to

Define the Scheduling in Multitasking Earlier we learned the concepts and advantages of multitasking. In a system in which one or more tasks( threads or processes) attempt to s