Intro to COA

Memory Hierarchy Design

This Memory Hierarchy Design is classified into 2 major types, which are explained below

1. Internal Memory

It is also known as Primary memory. It is directly accessible by the processor. It includes three basic levels, as given below

  • Zero level (CPU Registers)
  • level 1 (Cache Memory)
  • Level 2 (Main memory).

2. External Memory

It is also known as Secondary memory. It is accessible by the processor via the I/O Module. It includes level 3 (Magnetic Disk), level 4(Optical Disk and Magnetic Tape). Let explain the memory hierarchy with a block diagram as shown below,

Memory Hierarchy Design

  • Moving from the highest level (L0) to the lowest (L4) in the memory hierarchy results in increased capacity but longer access time.
  • When we move from bottom to top (level 4 to level 0) in the memory hierarchy, the cost per bit increases.