Which Operations are Considered in the FLOPS Measure?

Question

FLOPS (floating point operations per second) is a standard measure of performance of computing.

But, which floating point operations are considered? Addition? Multplication? Division? Doesn't each one of these take a different numbet of cycles to perform?

Answer 1

FLOPS is a measure usually associated with graphics cards (as it is a somewhat less useful measure in other areas).

Typically what is measured there is the performance of the fused multiply-add instruction FMA. This means that a GPU that is stated to have a peak performance of 1 TFLOPS will do a maximum of 1 trillion floating point operations of the form a * b + c = d in a second.

The reason this operation is used is that it is very essential to most operations a typical computer graphics application has to perform, such as computing the dot-product of vectors or multiplying matrices.