Investigation into the dependency between resource utilization, power consumption and performance in Multimedia servers Master thesis by Alaa Abdulkareem Hameed Brihi Supervisor: Dr.-Ing. habil. Waltenegus Dargie Advising Professor: Prof. Dr. rer. nat. habil. Dr. h. c Alexander Technische Universitat¨ Dresden Department of Computer Science Chair for Computer Network Augest 2012 i Declaration of Authorship In the following I, Alaa Brihi, want to state that this thesis titled ” Investigation into the dependency between resource utilization, power consumption and performance in Multimedia servers ” and the content presented in it are results of my own work. All published works of others, which were utilized in this thesis, are referenced and can be found in the Bibliography. Dresden 21.08.2012 ii Abstract Managing power consumption has become a major challenge of designing computer systems. Dynamic voltage frequency scaling (DVFS) is a power management technique, which aims to reduce the energy consumption of computing platforms by dynamically scaling the CPU frequency at run-time. The literature presents the usefulness of DVFS strategy in embedded systems, mobile devices, and wireless sensor networks. Recently, it has also been proposed for servers and data centers. This thesis investigates experimentally the relationship between the power consump- tion, resource utilization and the performance of a multimedia server under various voltage and frequency levels are used. It investigates the applicability of DVFS to re- duce the power consumed in two Multimedia servers’ platforms based on AMD Athlon X2 and Intel Duo2Core processors. The servers were setup with two of more realistic workloads which are selected and evaluated. The workloads have two different scenar- ios. In the first I/O intensive workload scenario, the servers hosted requests to down- load video files of known and available formats. In the second CPU-intensive workload scenario, the server employed a transcoder to convert between AVI, MPEG and FLV formats before the videos were downloaded videos; in case of the required formats are unaccepted. Through the achieved measurements, the experimental results indicated that there was not a meaningful relation between power consumption, CPU utilization and per- formance when the server runs the two different workload scenarios under different DVFS power management policies. Additionally, a comparison between AMD and In- tel server was made through calculation the energy-efficiency (EE) ratio, the results ob- served that under using frequency scaling policy, the AMD server was more energy efficient than the Intel one with I/O-intensive workload, while Intel server is more en- ergy efficient than AMD with CPU-intensive workload. It was conclude that the optimal DVFS power management policy is not clear, and it depends on many factors; such as the type of the workload, processor’s design and the maximum server frequency. iii Acknowledgment This dissertation would not have been possible without the guidance and the help of many people who has in one way or another contributed and extended their valuable assistance in the preparation and completion of this study. First and foremost, I would like to thank my supervisor, Dr. Waltenegus Dargie, for his support, worthy guidance and valuable comments in completion of this work. There are also other people who provided an enormous support during my thesis. I would like to thank Dr. Marious feldmann for helping and providing me with his a valuable suggestions. I also thank my Energy lab mates. many Thanks to Mr. jainjun Wen for helping me in the configure the machine. He was always willing to help and his best suggestions It would not have been possible to write this Master thesis without the help and sup- port of the kind people around me. I would like to thank Mrs.Rasha Faqeh, Mr.Muhammad Hassan Obeid and Mr. Mahmoud hafiez for their reviewing my writing A special gratitude and love goes to my family for their unfailing support. I thank my parents for their love, and for inspiring me to complete my higher education with their continued emotional support, which has often proven to be the deciding factor for my successes. Also I would like to thank my husband, Mr. Abdulqader Shawaa, whose love, encouragement and belief made everything possible, he has enriched my life and made every day happier. Special thanks go to my lovely son, Mohammed, for his sweet smile, his patience and understanding. Without their love, support and encouragement, I could never have gotten this far. Last but not the least; I would like to acknowledge that this thesis is a part of project SFB-912/1 2011: Energy-Efficient Service Execution. Contents 1 Introduction1 1.1 Power consumption................................2 1.2 Power management and energy efficiency overview.............4 1.3 Power Management Techniques........................5 1.3.1 Processor Power Management.....................7 1.4 Problem statement................................9 1.5 Thesis Organization................................ 10 2 Background and related work 11 2.1 Introduction.................................... 11 2.2 Data center..................................... 14 2.3 Server system................................... 17 2.3.1 CPU power management........................ 20 CONTENTS v 2.3.2 Operating system power management................. 24 3 Concept 29 3.1 DVFS support in Linux.............................. 29 3.1.1 CPUfreq Subsystem........................... 30 3.2 Methodology................................... 31 3.2.1 System architecture............................ 32 3.2.2 System components........................... 33 3.2.3 Measurement system.......................... 36 3.2.4 The experiment methodology...................... 38 3.3 Summary ...................................... 39 4 The experimental results 41 4.1 Measurements................................... 41 4.1.1 Power Consumption........................... 42 4.1.2 CPU utilization.............................. 57 4.1.3 Performance............................... 59 4.2 Experiments analysis............................... 60 4.3 Summary..................................... 75 5 Conclusions 77 vi CONTENTS 5.1 Summary and Conclusion............................ 77 5.2 Future work.................................... 80 List of Figures 1.1 All system power states as defined by the ACPI specification [33].....7 2.1 Moore’s law - the doubling of transistors count every two years.[43].... 12 2.2 worldwide expense to power and cool the Server Installed Base, 1996- 2010[45]....................................... 15 2.3 Server Power Consumption according to Intel Lab [4]............ 17 3.1 A high-level view of the CPUfreq subsystem................. 31 3.2 General architecture of experiment....................... 32 3.3 The server environment............................. 35 3.4 The experiment scenarios............................ 37 4.1 General Diagram of the main components in a motherboard........ 43 viii LIST OF FIGURES 4.2 The cumulative power consumption of overall power consumption of AMD server when (left) without transcoder : it runs Apache only. (right) with transcoder: it runs both Apache and the FFmpeg transcoder..... 45 4.3 The cumulative power consumption of overall power consumption of Intel server when (left) without transcoder : it runs Apache only,(right) with transcoder: it runs both Apache and the FFmpeg transcoder..... 45 4.4 The cumulative power consumption of 12 V CPU of AMD server when (left) without transcoder, (right) with transcoder............... 47 4.5 The cumulative power consumption of 12 V CPU of intel server when a) without transcoder, b) with transcoder..................... 48 4.6 The cumulative power consumption of 5 V supply line to motherboard of AMD server when (left) without transcoder, (right) with transcoder.. 49 4.7 The cumulative power consumption of 5 V supply line to motherboard of Intel server when (left) without transcoder, (right) with transcoder... 49 4.8 The cumulative of the memory used by the kernal in AMD server us- ing the four DVFS policies : (left) cache memory (right) virtual memory without transcoder workload.......................... 51 4.9 The cumulative of the memory used by the kernal in AMD server using the four DVFS policies : (left) cache memory (right) virtual memory with transcoder workload............................... 51 4.10 The cumulative power consumption of 3.3 V supply line to motherboard in AMD server (left) without transcoder, (right) with transcoder...... 52 4.11 The cumulative power consumption of 12 V supply line to motherboard of AMD server (left) without transcoder, (right) with transcoder...... 53 LIST OF FIGURES ix 4.12 The cumulative power consumption of 12V supply line to Hard Disk in AMD server (left) without transcoder, (right) with transcoder....... 54 4.13 The cumulative power consumption of 12V supply line to Hard Disk in Intel server (left) without transcoder, ( right) with transcoder........ 54 4.14 The cumulative power consumption of 5V supply line to Hard Disk in AMD server (left) without transcoder, (right) with transcoder....... 55 4.15 The cumulative power consumption of 5V supply line to Hard Disk in Intel server (left) without transcoder, (right) with transcoder........ 55 4.16 The cumulative of a) read operation, b) write operation of Hard Disk in AMD server without transcoder......................... 56 4.17 The cumulative of a) read operation, b) write operation of Hard Disk in