It is proved that the variance of the delay in a queueing system as well as the expectation of any convex increasing function of the delay attain their minima when customers leave the system according to a FIFO departure discipline. The relationship to a corresponding property of the FCFS service discipline with respect to the waiting time in the queue before service, is examined and some interesting differences are pointed out.
Bibliographical noteFunding Information:
This work was supported by the Natural Sciences and Engineering Research Council under Grant A4374.
- delay variance
- general queue
- optimality of FIFO departures
ASJC Scopus subject areas
- Management Science and Operations Research
- Industrial and Manufacturing Engineering
- Applied Mathematics