Green latency-aware data placement in data centers

Large-scale Internet applications provide service to end users by routing service requests to geographically distributed data centers. Two concerns exist in service provisioning by the data centers. One is that users require to experience low latency while accessing data from data centers. The other is to reduce the energy consumed by network transport and the servers in the data centers. In this paper, we tackle the problem of green data placement in data centers to strike a tradeoff among access latency, energy consumption of data centers and network transport. We propose two request-routing algorithms, GLDP-NS (Green Latency-aware Data Placement - No consideration of the current data placement Status of the server) and GLDP-WS (Green Latency-aware Data Placement - With consideration of the current data placement Status of the server). We show that the green latency-aware data placement problem is NP-complete and algorithm GLDP-NS is a 3-approximation algorithm for the data placement problem without considering the data placement status of the server. We evaluate the performance of the proposed algorithms through simulations, and the simulation results demonstrate that the proposed algorithms can achieve good integrated cost performance of the latency, the energy consumption of data centers and network transport.