Bit-level parallelism is a form of parallel computing based on increasing processor word size , depending on very-large-scale integration ( VLSI ) technology . Bit-level parallelism is a form of parallel computing based on increasing processor word size . From the advent of very-large-scale integration ( VLSI ) computer chip fabrication technology in the 1970s until about 1986 , advancements in computer architecture were done by increasing bit-level parallelism