Question

A 4-stage pipeline has the stage delays as 150, 120, 160 and 140

nanoseconds respectively. Registers that are used between the stages have a

delay of 5 nanoseconds each.

Question: Assuming constant clock rate, calculate the total time taken to

process 1000 data items on this pipeline.

Answer 1

Delay between each stage is 5 ns.

Total delay for 1st data item = 165$\times$4

               = 660 

For 1000 data items, first data will take 660 ns to complete and rest 

999 data will take max of all the stages that is 160 ns + 5 ns register delay

Total Delay = 660 + 999$\times$165 ns

=165.5 microsecond.