SRT Scheduling

Shortest-Remaining-Time (SRT) Scheduling

• The SRT is the preemtive counterpart of SJF and useful in time-sharing environment.
• In SRT scheduling, the process with the smallest estimated run-time to completion is run next, including new arrivals.
• In SJF scheme, once a job begin executing, it run to completion.
• In SJF scheme, a running process may be preempted by a new arrival process with shortest estimated run-time.
• The algorithm SRT has higher overhead than its counterpart SJF.
• The SRT must keep track of the elapsed time of the running process and must handle occasional preemptions.
• In this scheme, arrival of small processes will run almost immediately. However, longer jobs have even longer mean waiting time.