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

What is process control block, What is process control block? Every pro...

What is process control block? Every process is represented in the OS by a process control block. It has many pieces of information associated with an exact process.

Explain chaining to handle collision, Explain Chaining to Handle Collision ...

Explain Chaining to Handle Collision Chaining:  One easy scheme is to chain all collisions in lists attached to the suitable slot. This permits an unlimited number of collision

Explain deadlock, Explain Deadlock Every process in a set of processes ...

Explain Deadlock Every process in a set of processes is waiting for an event which only a process in the set can cause.

Cycle time, when demand is 24000 units/year, production rate is 48000 units...

when demand is 24000 units/year, production rate is 48000 units/year, setup cost is rs 200 per setup, carring cost is rs 20 per units/year, and economic batch quantity is 692.8203

What are the use of job queue, What are the use of job queues, ready queues...

What are the use of job queues, ready queues and device queues? As a process enters a system they are put in to a job queue. These queues having of all jobs in the system. The

What happens when you execute a program in unix, When you run a program on ...

When you run a program on your UNIX system, the system prepares a special environment for that program. This environment owns everything needed for the system to execute the progra

What are kernels and what do kernels do, What are kernels and what do kerne...

What are kernels and what do kernels do? The kernel is a program that comprises the central core of a computer operating   system. It has entire control over everything that

PSEUDO CODE FOR PROGRAM, THE PROGRAM WILL CHOOSE TWO RANDOM NUMBERS,THEN PR...

THE PROGRAM WILL CHOOSE TWO RANDOM NUMBERS,THEN PRINT THEM OUT AS AN ADDITION PROBLEM.THE PROGRAM WILL THEN ASK THE USERTO ENTER THE CORRECT ANSWER.IF THE ANSWER IS CORRECT,THE PRO

Draw and r chart and an x-bar chart, Thermostats are subjected to rigorous ...

Thermostats are subjected to rigorous testing before they are shipped to air conditioning technicians around the world. Results from the last five samples are shown in the table. D

Briefly explain about file system implementation, Briefly explain about fil...

Briefly explain about file system implementation? Several on-disk and in-memory structures are used to execute a file system. On disk, the file system may have information abou

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