In computer science dynamic
memory allocation is the allocation of memory storage for use in a computer program
during the runtime of that program. It is a way of distributing ownership of limited
memory resources among many pieces of data and code. A dynamically allocated object
remains allocated until it is deallocated explicitly, either by the programmer
or by a garbage collector this is notably different from automatic and static
memory allocation. It is said that such an object has dynamic lifetime.The problem
of fulfilling an allocation request, which involves finding a block of unused
memory of a certain size in the heap, is a difficult problem. A wide variety of
solutions have been proposed, including:
1)Free
lists
2)Paging
3)Buddy memory allocation
The
main problem for most dynamic memory allocation algorithms is to avoid both internal
and external fragmentation while keeping both allocation and deallocation efficient.
Also, most algorithms in use have the problem that a large number of small allocations
can cause wasted space due to collecting metadata; thus most programmers avoid
this, sometimes by using a strategy called chunking.