Speed -up and Efficiency

See the Fig. 6.

Figure 6: Left: Adding eight numbers sequentially. Right: Adding eight numbers with parallel processors.

• $S_p(n)=\frac{T_1(n)}{T_p(n)},\frac{7}{3}$; speed-up
• $E_p(n)=\frac{S_p(n)}{p},\frac{7/3}{4}$; efficiency