We consider the following Least-Used-Time-First (LUTF) preemptive priority scheduling policy. The LUTF scheduler recalculates each process' priority upon each interrupt: priority = used CPU time, where the used CPU time refers to the CPU time units the process has used since its arrival. We only consider two kinds of interrupts: timer interrupt and new process arrival. We assume the timer interrupt is triggered every time unit from Time 0 ( is a configurable parameter). We still assume that 0 is the highest priority. Therefore, the priority of any new process will be 0, and the more CPU time the process has used, the lower its priority becomes. By "preemptive", we still mean that any lower-priority process can be preempted by a higher-priority process. We still use FCFS for tie-break.

[4 points] Draw the Gantt chart for the five processes in previous questions under this LUTF policy with =1.

[2 points] Identify two important features of this LUTF policy with =1.