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- All Subjects: Smartphones
- Creators: Wu, Carole-Jean
- Creators: Wilkerson, Kelly
Description
A benchmark suite that is representative of the programs a processor typically executes is necessary to understand a processor's performance or energy consumption characteristics. The first contribution of this work addresses this need for mobile platforms with MobileBench, a selection of representative smartphone applications. In smartphones, like any other portable computing systems, energy is a limited resource. Based on the energy characterization of a commercial widely-used smartphone, application cores are found to consume a significant part of the total energy consumption of the device. With this insight, the subsequent part of this thesis focuses on the portion of energy that is spent to move data from the memory system to the application core's internal registers. The primary motivation for this work comes from the relatively higher power consumption associated with a data movement instruction compared to that of an arithmetic instruction. The data movement energy cost is worsened esp. in a System on Chip (SoC) because the amount of data received and exchanged in a SoC based smartphone increases at an explosive rate. A detailed investigation is performed to quantify the impact of data movement
on the overall energy consumption of a smartphone device. To aid this study, microbenchmarks that generate desired data movement patterns between different levels of the memory hierarchy are designed. Energy costs of data movement are then computed by measuring the instantaneous power consumption of the device when the micro benchmarks are executed. This work makes an extensive use of hardware performance counters to validate the memory access behavior of microbenchmarks and to characterize the energy consumed in moving data. Finally, the calculated energy costs of data movement are used to characterize the portion of energy that MobileBench applications spend in moving data. The results of this study show that a significant 35% of the total device energy is spent in data movement alone. Energy is an increasingly important criteria in the context of designing architectures for future smartphones and this thesis offers insights into data movement energy consumption.
on the overall energy consumption of a smartphone device. To aid this study, microbenchmarks that generate desired data movement patterns between different levels of the memory hierarchy are designed. Energy costs of data movement are then computed by measuring the instantaneous power consumption of the device when the micro benchmarks are executed. This work makes an extensive use of hardware performance counters to validate the memory access behavior of microbenchmarks and to characterize the energy consumed in moving data. Finally, the calculated energy costs of data movement are used to characterize the portion of energy that MobileBench applications spend in moving data. The results of this study show that a significant 35% of the total device energy is spent in data movement alone. Energy is an increasingly important criteria in the context of designing architectures for future smartphones and this thesis offers insights into data movement energy consumption.
ContributorsPandiyan, Dhinakaran (Author) / Wu, Carole-Jean (Thesis advisor) / Shrivastava, Aviral (Committee member) / Lee, Yann-Hang (Committee member) / Arizona State University (Publisher)
Created2014
Description
Smartphones have become increasingly common over the past few years, and mobile games continue to be the most common type of application (Apple, Inc., 2013). For many people, the social aspect of gaming is very important, and thus most mobile games include support for playing with multiple players. However, there is a lack of common knowledge about which implementation of this functionality is most favorable from a development standpoint. In this study, we evaluate three different types of multiplayer gameplay (pass-and-play, Bluetooth, and GameCenter) via development cost and user interviews. We find that pass-and-play, the most easily-implemented mode, is not favored by players due to its inconvenience. We also find that GameCenter is not as well favored as expected due to latency of GameCenter's servers, and that Bluetooth multiplayer is the most well favored for social play due to its similarity to real-life play. Despite there being a large overhead in developing and testing Bluetooth and GameCenter multiplayer due to Apple's development process, this is irrelevant since professional developers must enroll in this process anyway. Therefore, the most effective multiplayer mode to develop is mostly determined by whether Internet play is desirable: Bluetooth if not, GameCenter if so. Future studies involving more complete development work and more types of multiplayer modes could yield more promising results.
ContributorsBradley, Michael Robert (Author) / Collofello, James (Thesis director) / Wilkerson, Kelly (Committee member) / Barrett, The Honors College (Contributor) / School of Mathematical and Statistical Sciences (Contributor) / Computer Science and Engineering Program (Contributor)
Created2013-12
Description
Virtual machines and containers have steadily improved their performance over time as a result of innovations in their architecture and software ecosystems. Network functions and workloads are increasingly migrating to virtual environments, supported by developments in software defined networking (SDN) and network function virtualization (NFV). Previous performance analyses of virtual systems in this context often ignore significant performance gains that can be acheived with practical modifications to hypervisor and host systems. In this thesis, the network performance of containers and virtual machines are measured with standard network performance tools. The performance of these systems utilizing a standard 3.18.20 Linux kernel is compared to that of a realtime-tuned variant of the same kernel. This thesis motivates improving determinism in virtual systems with modifications to host and guest kernels and thoughtful process isolation. With the system modifications described, the median TCP bandwidth of KVM virtual machines over bridged network interfaces, is increased by 10.8% with a corresponding reduction in standard deviation of 87.6%. Docker containers see a 8.8% improvement in median bandwidth and 4.4% reduction in standard deviation of TCP measurements using similar bridged networking. System tuning also reduces the standard deviation of TCP request/response latency (TCP RR) over bridged interfaces by 86.8% for virtual machines and 97.9% for containers. Hardware devices assigned to virtual systems also see reductions in variance, although not as noteworthy.
ContributorsWelch, James Matthew (Author) / Syrotiuk, Violet R. (Thesis advisor) / Wu, Carole-Jean (Committee member) / Speyer, Gil (Committee member) / Arizona State University (Publisher)
Created2015
Description
The availability of a wide range of general purpose as well as accelerator cores on
modern smartphones means that a significant number of applications can be executed
on a smartphone simultaneously, resulting in an ever increasing demand on the memory
subsystem. While the increased computation capability is intended for improving
user experience, memory requests from each concurrent application exhibit unique
memory access patterns as well as specific timing constraints. If not considered, this
could lead to significant memory contention and result in lowered user experience.
This work first analyzes the impact of memory degradation caused by the interference
at the memory system for a broad range of commonly-used smartphone applications.
The real system characterization results show that smartphone applications,
such as web browsing and media playback, suffer significant performance degradation.
This is caused by shared resource contention at the application processor’s last-level
cache, the communication fabric, and the main memory.
Based on the detailed characterization results, rest of this thesis focuses on the
design of an effective memory interference mitigation technique. Since web browsing,
being one of the most commonly-used smartphone applications and represents many
html-based smartphone applications, my thesis focuses on meeting the performance
requirement of a web browser on a smartphone in the presence of background processes
and co-scheduled applications. My thesis proposes a light-weight user space frequency
governor to mitigate the degradation caused by interfering applications, by predicting
the performance and power consumption of web browsing. The governor selects an
optimal energy-efficient frequency setting periodically by using the statically-trained
performance and power models with dynamically-varying architecture and system
conditions, such as the memory access intensity of background processes and/or coscheduled applications, and temperature of cores. The governor has been extensively evaluated on a Nexus 5 smartphone over a diverse range of mobile workloads. By
operating at the most energy-efficient frequency setting in the presence of interference,
energy efficiency is improved by as much as 35% and with an average of 18% compared
to the existing interactive governor, while maintaining the satisfactory performance
of web page loading under 3 seconds.
modern smartphones means that a significant number of applications can be executed
on a smartphone simultaneously, resulting in an ever increasing demand on the memory
subsystem. While the increased computation capability is intended for improving
user experience, memory requests from each concurrent application exhibit unique
memory access patterns as well as specific timing constraints. If not considered, this
could lead to significant memory contention and result in lowered user experience.
This work first analyzes the impact of memory degradation caused by the interference
at the memory system for a broad range of commonly-used smartphone applications.
The real system characterization results show that smartphone applications,
such as web browsing and media playback, suffer significant performance degradation.
This is caused by shared resource contention at the application processor’s last-level
cache, the communication fabric, and the main memory.
Based on the detailed characterization results, rest of this thesis focuses on the
design of an effective memory interference mitigation technique. Since web browsing,
being one of the most commonly-used smartphone applications and represents many
html-based smartphone applications, my thesis focuses on meeting the performance
requirement of a web browser on a smartphone in the presence of background processes
and co-scheduled applications. My thesis proposes a light-weight user space frequency
governor to mitigate the degradation caused by interfering applications, by predicting
the performance and power consumption of web browsing. The governor selects an
optimal energy-efficient frequency setting periodically by using the statically-trained
performance and power models with dynamically-varying architecture and system
conditions, such as the memory access intensity of background processes and/or coscheduled applications, and temperature of cores. The governor has been extensively evaluated on a Nexus 5 smartphone over a diverse range of mobile workloads. By
operating at the most energy-efficient frequency setting in the presence of interference,
energy efficiency is improved by as much as 35% and with an average of 18% compared
to the existing interactive governor, while maintaining the satisfactory performance
of web page loading under 3 seconds.
ContributorsShingari, Davesh (Author) / Wu, Carole-Jean (Thesis advisor) / Vrudhula, Sarma (Committee member) / Shrivastava, Aviral (Committee member) / Arizona State University (Publisher)
Created2016
Description
Over the past several years, the three major mobile platforms have seen
tremendous growth and success; as a result, the platforms have been the target
of many malicious attacks. These attacks often request certain permissions in
order to carry out the malicious activities, and uninformed users usually grant
them. One prevalent example of this type of malware is one that requests
permission to the device’s SMS service, and once obtained, uses the SMS
service to accrue charges to the user. This type of attack is one of the most
prevalent on the Android application marketplace, and requires a long-term
solution. Replication of an attack is necessary to fully understand efficient
prevention methods, and due to the open-source nature of Android development,
to determine the likely mechanics of the attack as feasible.
This study uses the Hacker News application, an open source application
that is available for download through GitHub as a basis for creating a malware
application to study the SMS attack and explore prevention methods. From the
results and knowledge gained from both research and experimentation, a
proposition for a more secure operating system architecture was defined to
prevent and mitigate various attacks on mobile systems with a focus on SMS
attacks.
tremendous growth and success; as a result, the platforms have been the target
of many malicious attacks. These attacks often request certain permissions in
order to carry out the malicious activities, and uninformed users usually grant
them. One prevalent example of this type of malware is one that requests
permission to the device’s SMS service, and once obtained, uses the SMS
service to accrue charges to the user. This type of attack is one of the most
prevalent on the Android application marketplace, and requires a long-term
solution. Replication of an attack is necessary to fully understand efficient
prevention methods, and due to the open-source nature of Android development,
to determine the likely mechanics of the attack as feasible.
This study uses the Hacker News application, an open source application
that is available for download through GitHub as a basis for creating a malware
application to study the SMS attack and explore prevention methods. From the
results and knowledge gained from both research and experimentation, a
proposition for a more secure operating system architecture was defined to
prevent and mitigate various attacks on mobile systems with a focus on SMS
attacks.
ContributorsRomo, James Tyler (Co-author) / Rezende, Bryan (Co-author) / Whitaker, Jeremy (Co-author) / Ahn, Gail-Joon (Thesis director) / Wilkerson, Kelly (Committee member) / Conquest, Kevin (Committee member) / Barrett, The Honors College (Contributor) / Computer Science and Engineering Program (Contributor)
Created2013-05