Memory management

• Data processing and concurrent processing

Memory allocation

• Memory allocation is the assignment of an empty block of space in physical or virtual memory.

1. Static memory allocation

• The program is allocated memory at compile time.

• Stack is used for implementing static allocation.

  • Here memory cannot be reused.
  • static int a=10; # C/C++

• Methods and variables are created in Stack memory.

  • A stack frame is created whenever methods and variables are created.
    • These frames are destroyed automatically whenever methods are returned.

2. Dynamic memory allocation

• The program is allocated memory at runtime.

• Heap is used for implementing dynamic allocation.

  • Here memory can be freed and reused when not required.
  • int *p; p=new int # C/C++

• Dynamic memory allocation underlies Python memory management because everything in python is an object.

• Objects and instance variables are created in Heap memory.

  • As soon as the variables and functions are returned, dead objects will be garbage collected.

Python memory manager

• The raw memory allocator interacts with the memory manager of the OS to ensure that there’s space on the private heap.

  • There’s a private heap that contains all Python objects and data structures.

• Memory manager manages the heap on demand.

• It has object-specific allocators.

• If the objects get destroyed, it fills this space with a new object of the same size.

• It manages chunks of memory called blocks.

  • A collection of blocks makes up the pool.
    • Pools are created on Arenas.