1. GreenCloud: A Packet-level Simulator of Energy-aware Cloud Computing Data Centers Dzmitry Kliazovich ERCIM Fellow University of Luxembourg Apr 16, 2010

2. Outline Data center architectures  Two-tier, three-tier, and three-tier high-speed Structure of data center simulator  Energy efficiency, simulator components Case study data center simulations April 16, 2010 2 Dzmitry Kliazovich (dzmitry.kliazovich@uni.lu)

3. Why energy is important? Increased computing demand  Data centers are rapidly growing  Consume 10 to 100 times more energy per square foot than a typical office building Energy cost dynamics  Energy accounts for 10% of data center operational expenses (OPEX) and can rise to 50% in the next few years  Accompanying cooling system costs $2-$5 million per year April 16, 2010 3 Dzmitry Kliazovich (dzmitry.kliazovich@uni.lu)

4. Distribution of data center energy consumption April 16, 2010 4 Dzmitry Kliazovich (dzmitry.kliazovich@uni.lu)

5. Data center architectures Two-tier data center architecture  Access and Core layers  1 GE and 10 GE links  Full mesh core network  Load balancing using ICMP April 16, 2010 5 Dzmitry Kliazovich (dzmitry.kliazovich@uni.lu)

6. Data center architectures Three-tier data center architecture  Access, Aggregation, and Core layers  Scales to over 10,000 servers  8-way ECMP load balancing April 16, 2010 6 Dzmitry Kliazovich (dzmitry.kliazovich@uni.lu)

7. Data center architectures Three-tier High-Speed data center architecture  Increased core network bandwidth  2-way ECMP load balancing  100 GE standard (IEEE 802.3ba) still in works since Nov 2007 April 16, 2010 7 Dzmitry Kliazovich (dzmitry.kliazovich@uni.lu)

8. Data center simulator Greencloud is an extension of NS-2 network simulator for energy-aware cloud computing simulations Provides packet-level simulation dynamics Focused on workload distribution strategies and energy consumption models of simulator components (servers, switches, links, etc.) Dzmitry Kliazovich (dzmitry.kliazovich@uni.lu) 8 April 16, 2010

9. Data center simulator Dzmitry Kliazovich (dzmitry.kliazovich@uni.lu) 9 April 16, 2010

10. Simulator components Servers  Responsible for task execution  Single-core nodes  Preset processing limit in MIPS or FLOPS Supported power management modes  DVFS:Dynamic Voltage/Frequency Scaling  DNS:Dynamic Shutdown  Both:DNS if server is idle, DVFS otherwise Dzmitry Kliazovich (dzmitry.kliazovich@uni.lu) 10 April 16, 2010

11. Simulator components Servers’ Energy Model Dzmitry Kliazovich (dzmitry.kliazovich@uni.lu) 11 April 16, 2010 CPU memory modules, disks, I/O resources Idle server consumes about 66% of the peak load for all CPU frequencies

12. Simulator components Switches  Most common Top-of-Rack (ToR) switches typically operate at Layer-2 interconnecting gigabit links in the access network  Aggregation and core networks host Layer-3 switches operating at 10 GE (or 100 GE) Links  Transceivers’ power consumption depends on the quality of signal transmission in cables and is proportional to their cost  1 GE links: 0.4W is consumed for 100 meter transmissions over twisted pair  10 GE links: 1W is consumed for 300 meter transmission over optical fiber Supported power management modes  DVFS, DNS, or both Dzmitry Kliazovich (dzmitry.kliazovich@uni.lu) 12 April 16, 2010

13. Simulator components Switches’ Energy Model Dzmitry Kliazovich (dzmitry.kliazovich@uni.lu) 13 April 16, 2010 Chassis ~ 36% Linecards ~ 53% Port transceivers ~ 11%

14. Simulator components Workloads  Model cloud user applications (social networking, instant messaging, content distribution, etc.) Workload properties  Computational: MIPS, duration  Communicational: workload size, its internal and external transfers Generation  Trace-driven  Using random distribution (Exp, Pareto, etc.) Dzmitry Kliazovich (dzmitry.kliazovich@uni.lu) 14 April 16, 2010

15. Simulation Setup Data center architectures  Two-tier (2T), three-tier (3T), and three-tier high-speed (3Ths) Simulation parameters  Average data center load is 30%  1536 computing servers  1, 10, and 100 GE links with 10 ns delay  4500 bytes workloads (3 Ethernet packets)  60 minutes of simulation time Dzmitry Kliazovich (dzmitry.kliazovich@uni.lu) 15 April 16, 2010

16. Simulation Setup Energy-aware “green” scheduler Dzmitry Kliazovich (dzmitry.kliazovich@uni.lu) 16 April 16, 2010 Servers at the peak load Under-loaded servers, DVFS can be applied Idle servers, DNS can be applied

17. Evaluation results Distribution of energy consumption in data center Dzmitry Kliazovich (dzmitry.kliazovich@uni.lu) 17 April 16, 2010

18. Evaluation results Comparison of energy-efficiency schemes Dzmitry Kliazovich (dzmitry.kliazovich@uni.lu) 18 April 16, 2010

19. Conclusions Energy consumption is becoming a concern in cloud computing data centers Developed a packet-level simulator for energy-aware data centers Obtained results compare the performance of dynamic voltage/frequency scaling (DVFS) and dynamic server/network shutdown (DNS) schemes Future work will focus on adding storage area network as well as on the development of novel workload consolidation and traffic aggregation techniques Dzmitry Kliazovich (dzmitry.kliazovich@uni.lu) 19 April 16, 2010

20. Thank you! April 16, 2010 20 Dzmitry Kliazovich (dzmitry.kliazovich@uni.lu)