Weconsider the task assignment problem to heterogeneous parallel serverswith switching delay, where servers can be switched off to save energy. However, switching a server back on involves a constant server-specific delay. We will use one step of policy iteration from a starting policy such as Bernoulli splitting, in order to derive efficient task assignment (dispatching) policies that minimize...

1 (m, k)-firm means at least m deadlines should be met among any k consecutive task invocations or message transmissions. Providing (m, k)-firm guarantee is becoming attractive as it proposes an alternative between hard real-time guarantee (case of m = k) and soft (or probabilistic) real-time guarantee with p = m/k (when m, k → ∞) and allows more effective utilization of server resources (proce...

this paper analyzes an m/m/2 queueing system with two heterogeneous servers. both servers goes on vacation when there is no customers waiting for service after this server 1 is always available but the other goes on vacation whenever server 2 is idle. the vacationing server however, returns to serve at a low rate as an arrival finds the other server busy. the system is analyzed in the steady st...

The problem of optimal jobs assignment to heterogeneous servers arises in many applications. The problem of optimal jobs assignment for two heterogeneous servers with respect to minimization of long run average mean number jobs in the system was considered in [1], where it was shown that the policy, which minimizes the number of customers in the system, has a threshold property and consists in ...

Differentiated service approach has been proposed as a potential solution to provide Quality of Services (QoS) in the next generation Internet. The ultimate goal of end-to-end service differentiation can be achieved by complementing the network-level QoS with the service differentiation at the Internet servers. In this paper, we have presented a detailed study of the performance of service diff...

We consider a distributed server system model and ask which policy should be used for assigning tasks to hosts. In our model each host processes tasks in First-Come-First-Serve order and the task's service demand is known in advance. We consider four task assignment policies commonly proposed for such distributed server systems: Round-Robin, Random, Size-Based, in which all tasks within a give ...

We consider a distributed server system model and ask which policy should be used for assigning tasks to hosts. In our model each host processes tasks in First-Come-First-Serve order and the task's service demand is known in advance. We consider four task assignment policies commonly proposed for such distributed server systems: RoundRobin, Random, Size-Based, in which all tasks within a give s...

High-performance servers and high-speed networks will form the backbone of the infrastructure required for distributed multimedia information systems. A server for an interactive distributed multimedia system may require thousands of gigabytes of storage space and high I/O bandwidth. In order to maximize system utilization and, thus, minimize cost, it is essential that the load be balanced amon...

We introduce the problem of load-distance balancing in assigning users of a delay-sensitive networked application to servers. We model the service delay experienced by a user as a sum of a network-incurred delay, which depends on its network distance from the server, and a server-incurred delay, stemming from the load on the server. The problem is to minimize the maximum service delay among all...

In this paper, a single server queueing system operating in doubly stochastic environment is analysed. The random makes transitions among N levels controlled by switch which performs the task of assigning job to server. resides level k till completion service last customer and immediately reports get new job. generates set up time waits arrives assigns any one with positive probability governed...