Cache Memory and Virtual Memory

1. Cache Memory :

A small memory between CPU and main memory is called cache memory. The access time closer to the processing speed of the CPU. Cache memory acts as a high-speed buffer between CPU and main memory and is used to temporarily store very active data and instructions during processing. Since the cache memory is faster than main memory, the processing speed is increased by making data and instruction needed in present processing available in the cache memory.

Advantages :

1. It stores the current information.

2. Reduces the access time.

3. Increases the performance.

4. Increases the speed of CPU.

5. Fast accessing.

2. Virtual Memory :

A process cannot be loaded in a system whose main memory size is less than the total memory required by the process.

A process cannot be loaded and has to keep waiting for its execution to start until sufficient free memory for loading the entire process becomes available. This may delay a process's turn around time to great extent. Virtual memory is a memory management scheme that overcomes this limitations by allowing the execution of processes that might not be completely loaded in the main memory. That is, it does not require the entire process not be in memory before the process can execute.