Mark-sweep, Operating System

Assignment Help:

The objects that a program can access directly are those objects which are referenced by local vari-ables on the processor stack, or by any global/static variables that refer to objects, or by variables in CPU registers. In the context of garbage collection, these variables are called the roots. An object is indirectly accessible if it is referenced by a ?eld in some other (directly or indirectly) accessible object. An accessible object is said to be live. Conversely, an object which is not live is garbage.

Note that heap objects which are live are indirectly accessible from the roots or other heap objects. The idea of mark-sweep is relatively straightforward. We start at the roots, and recursively visit every object accessible through pointers, marking them as live. At the end of the process, every thing not marked is considered garbage and will be deleted. Notice that mark-sweep can perform lazy garbage collection, in the sense that it does not necessarily need to remove the garbage immediately.

Note thatmark-sweep does not clean upmemory which is allocated, but simply never used. Also, periodically we have to visit all objects recursively, starting from the roots. For a large program, this will be slow. This is a problem with the traditional mark-sweep algorithm.


Related Discussions:- Mark-sweep

How is memory management done using bit maps?, How is memory management don...

How is memory management done using bit maps? A bit map is here in this we signify the bit value as 0 or 1. 1-hole 0-process In this we are able to represent the proce

What are the allocation methods of a disk space, What are the allocation me...

What are the allocation methods of a disk space? Methods of allocating disk space which are widely in use are a. Contiguous allocation b. Linked allocation c. Indexed

Difference between sam and active directory, Question: (a) Write down ...

Question: (a) Write down short notes on the different versions of Windows server 2003 mentioned below: 1. Windows Server 2003, Web Edition 2. Windows Server 2003, Stand

Describe the purpose of the open and close operations, Q. Describe the pur...

Q. Describe the purpose of the open() and close() operations. Answer: The open() operation notifies the system that the named file is about to become active. The c

Comparing, Compare 2 different operating systems.

Compare 2 different operating systems.

Explain memory management using buddy sustem, MEMORY MANAGEMENT USING BUDDY...

MEMORY MANAGEMENT USING BUDDY SUSTEM Here we are dividing the memory as powers of two as well as we are selecting the space which is smallest but large enough to hold a process

An operating system for a real-time environment, Q. What is the major diffi...

Q. What is the major difficulty that a programmer should overcome in writing an operating system for a real-time environment? Answer: The major difficulty is keeping the oper

List post-installation procedures that need to be performed, Problem: (...

Problem: (a) Based on your experience in setting up Windows 2003 Server operating system, briefly describe the twelve different steps in which the installation is conducted du

Memory management, example of first fit best fit and worst fit

example of first fit best fit and worst fit

Determine what the blocking factor of a file is, Determine what the “blocki...

Determine what the “blocking factor” of a file is Blocking factor is the number of logical records in one physical record

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd