COMPUTER FUNDAMENTALS

Detailed explanation-1: -The most straightforward model for memory consistency is called sequential consistency. Sequential consistency requires that the result of any execution be the same as if the memory accesses executed by each processor were kept in order and the accesses among different processors were arbitrarily interleaved.

Detailed explanation-2: -Sequential consistency implies that operations appear to take place in some total order. This order has to be consistent with the order of operations on each individual process. Therefore, reads may be stable in terms of real-time, but not in logical time.

Detailed explanation-3: -The sequential consistency model is implemented by stalling the processor till the completion of previously issued operation. The weak consistency model is implemented by using a transaction counter in the platform hardware to avoid the interference between the data and synchronization operations.

Detailed explanation-4: -Sequential consistency can be achieved simply by hardware implementation, while release consistency is also based on an observation that most of the parallel programs are properly synchronized.