As there has been rapid development in the electronics and communication space, the industry has released the hardware components with cost-effective and highly efficient modes. In this direction, computer architecture is designed with the interconnected multiple processors types in two forms:
- Tightly coupled system
- Loosely coupled system
In tightly coupled system, there is a single system-wide primary memory, which is shared by all the processors in the ecosystem. As the name depicts, any sort of communication is executed in the closed tightly couple environment of the common shared memory route, as defined here:
Let's take an example in the multiprocessor environment. Processor 1 writes value 100 into the shared memory address location ADDR1. Subsequent reads by the rest of the processors will be the same value, 100, from the ADDR1 location. It will be valid until there are any further updates on the specific location.
If you take the same scenario in the loosely coupled system, each processor contains its own independent local memory to persist the value. It doesn't share any memory location across the processors. By design, message-bound inter-process communication is established. By architecture, this is termed Message Driven Architecture in the computing industry.
With the concept of fundamentals, the first version tightly coupled system is built using parallel computing. The second version Loosely Coupled system is based on distributed computing.
On analyzing the need for hard disk capacity (GB) in personal computers, the plot is interestingly logarithmic. The lesson learned is that the industry fitted line corresponds to exponential growth.
