Garbage collection, Operating System

Assignment Help:

The dynamic memory allocator is a layer between the application and the OS, managing heap objects. When a program requests memory from the allocator (via malloc(), for instance), the allocator will return a pointer (or reference) to a piece of memory of the appropriate size. When the program is done with the memory, the memory should be released back to the allocator. Languages such as C and C++ leave this job to the programmer to perform manually, for example by using free(). On the other hand, languages such as Java, python, etc automatically manage dynamically-allocated memory, which makes the programmer's life easier, and can eliminate entire classes of memory management bugs.

Although using free() and delete is relatively simple, it can be tricky to get them right. A signi?cant fraction of bugs in C and C++ programs are related to manual memory management. If we forget to free objects, we end up with memory leaks; if we free memory too soon, we end up with "dangling pointers"; also, we can try to do weird things, like performing double frees, etc. Therefore, a process that manages memory automatically is clearly useful. The most important concept for correctly implementing a garbage collector is that of live objects: a live object is any object that can still be reached through one (or more) pointers.


Related Discussions:- Garbage collection

List five services provided by an operating system, List five services prov...

List five services provided by an operating system. Explain how each provides convenience to the users. Explain also in which cases it would be impossible for user-level programs t

Explain acyclic-graph directories, Acyclic-graph directories An acyclic...

Acyclic-graph directories An acyclic graph permits directories to have shared subdirectories and files. The similar file or subdirectory may be in two dissimilar directories. A

Major locking errors, When programming with threads, there are three very c...

When programming with threads, there are three very common mistakes that programmers often make: 1. locking twice (depending on the system and type of lock, can cause crashes, h

Explain hierarchical paging method, Hierarchical paging method Most mo...

Hierarchical paging method Most modern computer systems maintain a large logical-address space. In this situation the page table itself turns into excessively large. To remedy

Describe swapping technique in unix systems, Describe swapping technique in...

Describe swapping technique in UNIX systems. Swapping is used to control memory contention among processes. If there is excessively much memory contention, processes are swappe

Explain benefits of time-sharing system, Under what circumstances would a ...

Under what circumstances would a user be better off using a time-sharing system, rather than a personal computer or single-user workstation? When there are some other users, th

Action taken by the operating system when a page fault occur, Q. Under what...

Q. Under what conditions do page faults occur? Explain the actions taken by the operating system when a page fault occurs. Answer: A page fault take places when an access to

Index node (inode), A file system depends on data structures about the file...

A file system depends on data structures about the files, beside the file structure. The former is named metadata-data that defines data. Each file is accumulated with an inode, wh

Activities of operating system - memory management, Q. What are the three m...

Q. What are the three main activities of an operating system in regard to memory management? Answer: a. Keep follows of which parts of memory are currently being used and

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