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

Do ratio analysis of financial statements, Do ratio analysis by comparing t...

Do ratio analysis by comparing the four companies financial statements, analysis and interpretation on the four-basic group : (Refer to attachment A) Liquidity ratio Asset

What is the main difficulty real-time environment, What is the main difficu...

What is the main difficulty that a programmer must overcome in writing an operating system for a real-time environment? The main difficulty is keeping the operating system with

What is the design issues involved in segmentation?, SEGMENTATION HARDWARE ...

SEGMENTATION HARDWARE An execution to map two-dimensional user-defined addresses into one-dimensional physical addresses. This mapping is affected by means of segment table. Ev

What are the advantages of linked allocation, What are the advantages of Li...

What are the advantages of Linked allocation? The benefits are a. No external fragmentation b. Size of the file does not require to be declared

Define most common phase structured grammar, Which is most common phase str...

Which is most common phase structured grammar? Most common phase structured grammar is Context – Sensitive

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

Control the access of the three global variables, Give a brief introduction...

Give a brief introduction about the operation of your program and show that you understand the idea behind threads and mutual exclusion variable. Why do we need to use mutual exclu

Default domain controllers policy gpo, Question: (a) Distinguish betwee...

Question: (a) Distinguish between local and active directory Group Policy in Windows Server 2008? (b) Describe the three areas of account Policies that can be managed thro

Multi-level page tables, Multi-level page tables are tree-like structures t...

Multi-level page tables are tree-like structures to hold page tables. As an example, consider a two- level page table, again on a 32-bit architecture with 212 = 4 kbyte pages. Now,

Nachos file system, File System Interface and Implementation The Nachos ...

File System Interface and Implementation The Nachos file system, as distributed, uses a single-level index allocation method for data allocation of files. In the current design,

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