The thesis ``Ytelse og skalerbarhet i distribuertetelekommunikasjonssystemer'' contains an analysis of the behavior of six differentalgorithms. The algorithms are simple, and they schedule customers from multiple queuesin a Call-center. A simulator is implemented i Java tomeasure the customers waiting time and the non-operating time of theagents. The algorithms are compared to each other so that the bestmethod can be chosen. An example of a good method is one that givesthe customers short waiting time.
Two different cases was tested. CASE 1 was set up to handle twoqueues with the same arrival rate. One type of agents served bothof the queues, and the average serving rate was estimated tothe same value for all of the arriving customers. In this case,the algorithms produced almost the same result when the arrival rate, serving rate or the number of agents in the system was changed.
CASE 2 was configured with three different agent types and threequeues. Each queue had their own arrival rate, and the agent groups haddifferent serving rate, they also served different sets ofqueues. In this case the result from the algorithms differ. Thecustomers waiting time and the agents non-operating time was dependenton the choice of algorithm.
When the arrival rate was changed, the static algorithm type gaveincreased waiting time for the customers in the queue where thearrival rate increased. The customers in the other queues did just get a insignificance increase in their waiting time. For dynamic queue schedulingthe result was a little different. When the arrival rate increased inone queue, the waiting time increased in all queues in thesystem. This is because these algorithms analyse each queue loadbefore an customer is picked from a queue.
The agents non-operating time decreased more when a dynamicalgorithm was used to schedule the next customer. The reduction of thenon-operating time and the degree of increase in waiting time shows thatdynamic algorithms should be chosen if the system is going tohave high performance and scalability.