search query: @keyword energy effíciency / total: 167
reference: 48 / 167
« previous | next »
Author:Gebrehiwot, Misikir
Title:Energy-Aware Queueing Models and Controls for Server Farms
Publication type:Master's thesis
Publication year:2014
Pages:viii + 58 s. + liitt. 24      Language:   eng
Department/School:Tietoliikenne- ja tietoverkkotekniikan laitos
Main subject:Networking Technology   (S3029)
Supervisor:Aalto, Samuli
Instructor:Lassila, Pasi
Electronic version URL: http://urn.fi/URN:NBN:fi:aalto-201406262260
OEVS:
Electronic archive copy is available via Aalto Thesis Database.
Instructions

Reading digital theses in the closed network of the Aalto University Harald Herlin Learning Centre

In the closed network of Learning Centre you can read digital and digitized theses not available in the open network.

The Learning Centre contact details and opening hours: https://learningcentre.aalto.fi/en/harald-herlin-learning-centre/

You can read theses on the Learning Centre customer computers, which are available on all floors.

Logging on to the customer computers

  • Aalto University staff members log on to the customer computer using the Aalto username and password.
  • Other customers log on using a shared username and password.

Opening a thesis

  • On the desktop of the customer computers, you will find an icon titled:

    Aalto Thesis Database

  • Click on the icon to search for and open the thesis you are looking for from Aaltodoc database. You can find the thesis file by clicking the link on the OEV or OEVS field.

Reading the thesis

  • You can either print the thesis or read it on the customer computer screen.
  • You cannot save the thesis file on a flash drive or email it.
  • You cannot copy text or images from the file.
  • You cannot edit the file.

Printing the thesis

  • You can print the thesis for your personal study or research use.
  • Aalto University students and staff members may print black-and-white prints on the PrintingPoint devices when using the computer with personal Aalto username and password. Color printing is possible using the printer u90203-psc3, which is located near the customer service. Color printing is subject to a charge to Aalto University students and staff members.
  • Other customers can use the printer u90203-psc3. All printing is subject to a charge to non-University members.
Location:P1 Ark Aalto  1623   | Archive
Keywords:server farms
queueing models
energy efficiency
Abstract (eng):Data centers are known to consume substantial amounts of energy.
Together with the rising cost of energy, this has created a major concern.
Server farms, being integral parts of data centers, waste energy while they are idle.
Turning idle servers off may appear to eliminate this wastage.
However, turning the server back on at the arrival of the next service request incurs a setup cost in the form of additional delays and energy consumption.
Thus, a careful analysis is required to come up with the optimal server control policy.
In this thesis, a queueing theoretic analysis of single server systems is carried out to determine optimal server control policies.
Additionally, multiple server systems are also be studied through numerical methods.
In this case, the task assignment policies that define how incoming requests are routed among the servers are also studied along with the control policies.
The results of this study illustrate that the optimal control policy for a single server system leaves an idle server on or switches it off immediately when there is no request to serve.
This is a general result that does not depend on service, setup and idling time distributions.
However, in the case of multiserver systems, there is a plethora of choices for task assignment and server control policies.
Our study indicates that the combination of the Join the Shortest Queue and Most Recently Busy task assignment policies can save up to 30% of the system cost if the control policy applied can wait for a specific amount of time before turning a server off.
Moreover, a similar gain can be achieved by the simple Join the Shortest Queue task assignment policy when it is used along with a control policy that leaves an optimized number of servers on while switching the remaining servers off when they become idle.
ED:2014-08-03
INSSI record number: 49464
+ add basket
« previous | next »
INSSI