10% 10% CPU CPU 0% 100% Memory Memory 0% 100% Disk Dkk 100% 100% Terminal Terminal 0% 0% 100%0 Printer Printer 0% 0% Job History JoB JOB2 lOB Job History JOBI JOBe 15 30 JOB minutes (a) Uniprogramming (b) Multiprogramming Figure 2.6 Utilization Histograms