Penerapan Konsolidasi Beban Kerja Kluster Web server Secara Dinamis Dengan Melakukan Klasifikasi Beban Kerja Server Menggunakan Pendekatan Backpropagation Neural Network

Meningkatnya permintaan pengguna aplikasi WWW telah menyebabkan peningkatan yang sepadan dalam penggunaan sumber daya kluster server web. Penelitian ini mengkaji tentang penyediaan sumber daya web server berdasarkan parameter beban kerja server (load average CPU). Data yang digunakan adalah akses terhadap web server yang melayani applikasi Sistem Informasi Akademik Mahasiswa Universitas Brawijaya (SIAM-UB). Penggunaan sumber daya server secara maksimal (beban puncak) terjadi pada periode registrasi mahasiswa, yaitu lebih dari 65000 mahasiswa akan mengakses server SIAM secara bersamaan. Jumlah permintaan yang dilayani server dalam 1 hari dapat mencapai 1.7juta permintaan. Pada penelitian ini, dilakukan prediksi (klasifikasi) konsolidasi beban kerja CPU dalam kluster web server untuk penyediaan sumber daya server yang optimal. Prediksi konsolidasi beban kerja server diklasifikasikan menjadi 3 kelas, yaitu: Min (0-2), Medium (3-6), Maximum (n > 7). Metode backpropagation neural network (BNN) digunakan untuk memprediksi kelas konsolidasi beban kerja server berdasarkan parameter input penggunaan CPU, memory, jaringan (throughput) dan jumlah IP akses. Arsitektur BNN dengan 32 input, 2 hidden layer dengan jumlah neuoron h1 512; h2 32, 3 output, dan learning rate 0.00001, menghasilkan bobot yang mampu melakukan klasifikasi konsolidasi beban kerja CPU dengan tingkat precision 90%, tingkat sensitivity 0.9, dan tingkat akurasi 93%

Correlation-Aware Virtual Machine Allocation for Energy-Efficient Datacenters

Server consolidation plays a key role to mitigate the continuous power increase of datacenters. The recent advent of scale-out applications (e.g., web search, MapReduce, etc.) necessitate the revisit of existing server consolidation solutions due to distinctively different characteristics compared to traditional high-performance computing (HPC), i.e., user interactive, latency critical, and operations on large data sets split across a number of servers. This paper presents a power saving solution for datacenters that especially targets the distinctive characteristics of the scale-out applications. More specifically, we take into account correlation information of core utilization among virtual machines (VMs) in server consolidation to lower actual peak server utilization. Then, we utilize this reduction to achieve further power savings by aggressively-yet-safely lowering the server operating voltage and frequency level. We have validated the effectiveness of the proposed solution using 1) multiple clusters of real-life scale-out application workloads based web search and 2) utilization traces obtained from real datacenter setups. According to our experiments, the proposed solution provides up to 13.7% power savings with up to 15.6% improvement of Quality-of-Service (QoS) compared to existing correlation-aware VM allocation schemes for datacenters

Joint Computing and Electric Systems Optimization for Green Datacenters

This chapter presents an optimization framework to manage green datacenters using multilevel energy reduction techniques in a joint approach. A green datacenter exploits renewable energy sources and active Uninterruptible Power Supply (UPS) units to reduce the energy intake from the grid while improving its Quality of Service (QoS). At server level, the state-of-the-art correlation-aware Virtual Machines (VMs) consolidation technique allows to maximize server’s energy efficiency. At system level, heterogeneous Energy Storage Systems (ESS) replace standard UPSs, while a dedicated optimization strategy aims at maximizing the lifetime of the battery banks and to reduce the energy bill, considering the load of the servers. Results demonstrate, under different number of VMs in the system, up to 11.6% energy savings, 10.4% improvement of QoS compared to existing correlation-aware VM allocation schemes for datacenters and up to 96% electricity bill savings

Power-Thermal Modeling and Control of Energy-Efficient Servers and Datacenters

Recently, the energy-efficiency constraints have become the dominant limiting factor for datacenters due to their unprecedented increase of growing size and electrical power demands. In this chapter we explain the power and thermal modeling and control solutions which can play a key role to reduce the power consumption of datacenters considering time-varying workload characteristics while maintaining the performance requirements and the maximum temperature constraints. We first explain simple-yet-accurate power and temperature models for computing servers, and then, extend the model to cover computing servers and cooling infrastructure of datacenters. Second, we present the power and thermal management solutions for servers manipulating various control knobs such as voltage and frequency of servers, workload allocation, and even cooling capability, especially, flow rate of liquid cooled servers). Finally, we present the solution to minimize the server clusters of datacenters by proposing a solution which judiciously allocates virtual machines to servers considering their correlation, and then, the joint optimization solution which enables to minimize the total energy consumption of datacenters with hybrid cooling architecture (including the computing servers and the cooling infrastructure of datacenters)