In books, I have read that FCFS suffers from convoy effect. I think that even SJF and priority(both preemptive and non preemptive) can suffer from convoy effect.
In SJF, if a process with large burst time arrives first then no other process can preempt it causing convoy effect.
In preemptive and non preemptive priority, if all processes arrive at time 0 and if a high priority process has very large burst time, it can lead to convoy effect as no other process can preempt this process because they all have lesser priority.
Am I correct?