Consider four process all are arriving at time zero, with total execution time of 20, 10, 10 and 20 unit respectively. Each process spends the first 20% of execution time doing CPU, the next 60%of doing I/O computation and the last 20% of time doing CPU computation again. The operating system uses longest time remaining first scheduling algorithm (LRTF) and schedules a new process either when running process get blocked I/O or when the running process finishes its CPU burst. Assume that are I/O operations can be overlapped as much as possible. What is the completion time of process P0. [Note: When same burst occurs for multiple process high priority given to lowest process id].
schedules a new process either when running process get blocked I/O or when the running process finishes its CPU burst
doesn't this line makes it LTF (non preemptive) ??
because they solve this by LRTF(preemptive ).