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

Case studies, Did Abhinav agree to the initial timeline requested by Rebecc...

Did Abhinav agree to the initial timeline requested by Rebecca

What is critical section problem, What is critical section problem? Con...

What is critical section problem? Consider a system consists of 'n' processes. Every process has segment of code called a critical section, in which the process might be changi

Producer – consumer process, Step by step displays the content, and the fin...

Step by step displays the content, and the final result of the list ("buffer") of 6 elements as the initial values ??and the following elements which are produced (NEXTP) or consum

Define dynamic linking, Define dynamic linking. Dynamic linking is same...

Define dynamic linking. Dynamic linking is same to dynamic loading, rather that loading being postponed unless execution time, linking is postponed. This feature is usually use

What circumstances is a token-passing network more effectual, Q. In what ci...

Q. In what circumstances is a token-passing network more effectual than an Ethernet network? Answer: A token ring is extremely effective under high sustained load as no colli

List antivirus techniques used for protection purposes, Question: a) Th...

Question: a) There are main goals of data security. List them and elaborate on how they provide protection. b) Describe threats associated with data security. c) Describe

Show the services which provided by operating system, Q. Show the services ...

Q. Show the services which provided by operating system? A) Resource Allocation: If there are more than one user or jobs running at the same instance then resource

Embedded systems design or hardware design, You have been requested by your...

You have been requested by your Senior Engineer to design an Engine Control Unit (ECU) and prepare a report detailing your proposed solution. The client requires a design for a mic

Conversion of binary to hex, Take the binary number and divide it into grou...

Take the binary number and divide it into groups of 4 bits starting from the right hand side , if no group of 4 exists fill out leading 0's, then convert each group of 4 to a hex n

Interpreters, Use and overview? Pure and impure interpreter?

Use and overview? Pure and impure interpreter?

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