The Experts below are selected from a list of 25035 Experts worldwide ranked by ideXlab platform
Franck Cappello - One of the best experts on this subject based on the ideXlab platform.
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A Hybrid Local Storage Transfer Scheme for Live Migration of I/O Intensive Workloads
2012Co-Authors: Bogdan Nicolae, Franck CappelloAbstract:Live migration of virtual machines (VMs) is key feature of virtualization that is extensively leveraged in IaaS cloud environments: it is the basic building block of several important features, such as load balancing, pro-active fault tolerance, power management, Online Maintenance, etc. While most live migration efforts concentrate on how to transfer the memory from source to destination during the migration process, comparatively little attention has been devoted to the transfer of storage. This problem is gaining increasing importance: due to performance reasons, virtual machines that run large-scale, data-intensive applications tend to rely on local storage, which poses a difficult challenge on live migration: it needs to handle storage transfer in addition to memory transfer. This paper proposes a memory-migration independent approach that addresses this challenge. It relies on a hybrid active push / prioritized prefetch strategy, which makes it highly resilient to rapid changes of disk state exhibited by I/O intensive workloads. At the same time, it is minimally intrusive in order to ensure a maximum of portability with a wide range of hypervisors. Large scale experiments that involve multiple simultaneous migrations of both synthetic benchmarks and a real scientific application show improvements of up to 10x faster migration time, 10x less bandwidth consumption and 8x less performance degradation over state-of-art.
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HPDC - A hybrid local storage transfer scheme for live migration of I/O intensive workloads
Proceedings of the 21st international symposium on High-Performance Parallel and Distributed Computing - HPDC '12, 2012Co-Authors: Bogdan Nicolae, Franck CappelloAbstract:International audienceLive migration of virtual machines (VMs) is key feature of virtualization that is extensively leveraged in IaaS cloud environments: it is the basic building block of several important features, such as load balancing, pro-active fault tolerance, power management, Online Maintenance, etc. While most live migration efforts concentrate on how to transfer the memory from source to destination during the migration process, comparatively little attention has been devoted to the transfer of storage. This problem is gaining increasing importance: due to performance reasons, virtual machines that run large-scale, data-intensive applications tend to rely on local storage, which poses a difficult challenge on live migration: it needs to handle storage transfer in addition to memory transfer. This paper proposes a memory-migration independent approach that addresses this challenge. It relies on a hybrid active push / prioritized prefetch strategy, which makes it highly resilient to rapid changes of disk state exhibited by I/O intensive workloads. At the same time, it is minimally intrusive in order to ensure a maximum of portability with a wide range of hypervisors. Large scale experiments that involve multiple simultaneous migrations of both synthetic benchmarks and a real scientific application show improvements of up to 10x faster migration time, 10x less bandwidth consumption and 8x less performance degradation over state-of-art
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Towards Efficient Live Migration of I/O Intensive Workloads: A Transparent Storage Transfer Proposal
2011Co-Authors: Bogdan Nicolae, Franck CappelloAbstract:Live migration of virtual machines (VMs) is key feature of virtualization that is extensively leveraged in IaaS cloud environments: it is the basic building block of several important features, such as load balancing, pro-active fault tolerance, power management, Online Maintenance, etc. While most live migration efforts concentrate on how to transfer the memory from source to destination during the migration process, comparatively little attention has been devoted to the transfer of storage. This problem is gaining increasing importance: due to performance reasons, virtual machines that run I/O intensive workloads tend to rely on local storage, which poses a difficult challenge on live migration: it needs to handle storage transfer in addition to memory transfer. This paper proposes a completely hypervisor-transparent approach that addresses this challenge. It relies on a hybrid active push-prioritized prefetch strategy, which makes it highly resilient to rapid changes of disk state exhibited by I/O intensive workloads. At the same time, transparency ensures a maximum of portability with a wide range of hypervisors. Large scale experiments that involve multiple simultaneous migrations of both synthetic benchmarks and a real scientific application show improvements of up to 10x faster migration time, 5x less bandwidth consumption and 62% less performance degradation over state-of-art.
Bogdan Nicolae - One of the best experts on this subject based on the ideXlab platform.
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A Hybrid Local Storage Transfer Scheme for Live Migration of I/O Intensive Workloads
2012Co-Authors: Bogdan Nicolae, Franck CappelloAbstract:Live migration of virtual machines (VMs) is key feature of virtualization that is extensively leveraged in IaaS cloud environments: it is the basic building block of several important features, such as load balancing, pro-active fault tolerance, power management, Online Maintenance, etc. While most live migration efforts concentrate on how to transfer the memory from source to destination during the migration process, comparatively little attention has been devoted to the transfer of storage. This problem is gaining increasing importance: due to performance reasons, virtual machines that run large-scale, data-intensive applications tend to rely on local storage, which poses a difficult challenge on live migration: it needs to handle storage transfer in addition to memory transfer. This paper proposes a memory-migration independent approach that addresses this challenge. It relies on a hybrid active push / prioritized prefetch strategy, which makes it highly resilient to rapid changes of disk state exhibited by I/O intensive workloads. At the same time, it is minimally intrusive in order to ensure a maximum of portability with a wide range of hypervisors. Large scale experiments that involve multiple simultaneous migrations of both synthetic benchmarks and a real scientific application show improvements of up to 10x faster migration time, 10x less bandwidth consumption and 8x less performance degradation over state-of-art.
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HPDC - A hybrid local storage transfer scheme for live migration of I/O intensive workloads
Proceedings of the 21st international symposium on High-Performance Parallel and Distributed Computing - HPDC '12, 2012Co-Authors: Bogdan Nicolae, Franck CappelloAbstract:International audienceLive migration of virtual machines (VMs) is key feature of virtualization that is extensively leveraged in IaaS cloud environments: it is the basic building block of several important features, such as load balancing, pro-active fault tolerance, power management, Online Maintenance, etc. While most live migration efforts concentrate on how to transfer the memory from source to destination during the migration process, comparatively little attention has been devoted to the transfer of storage. This problem is gaining increasing importance: due to performance reasons, virtual machines that run large-scale, data-intensive applications tend to rely on local storage, which poses a difficult challenge on live migration: it needs to handle storage transfer in addition to memory transfer. This paper proposes a memory-migration independent approach that addresses this challenge. It relies on a hybrid active push / prioritized prefetch strategy, which makes it highly resilient to rapid changes of disk state exhibited by I/O intensive workloads. At the same time, it is minimally intrusive in order to ensure a maximum of portability with a wide range of hypervisors. Large scale experiments that involve multiple simultaneous migrations of both synthetic benchmarks and a real scientific application show improvements of up to 10x faster migration time, 10x less bandwidth consumption and 8x less performance degradation over state-of-art
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Towards Efficient Live Migration of I/O Intensive Workloads: A Transparent Storage Transfer Proposal
2011Co-Authors: Bogdan Nicolae, Franck CappelloAbstract:Live migration of virtual machines (VMs) is key feature of virtualization that is extensively leveraged in IaaS cloud environments: it is the basic building block of several important features, such as load balancing, pro-active fault tolerance, power management, Online Maintenance, etc. While most live migration efforts concentrate on how to transfer the memory from source to destination during the migration process, comparatively little attention has been devoted to the transfer of storage. This problem is gaining increasing importance: due to performance reasons, virtual machines that run I/O intensive workloads tend to rely on local storage, which poses a difficult challenge on live migration: it needs to handle storage transfer in addition to memory transfer. This paper proposes a completely hypervisor-transparent approach that addresses this challenge. It relies on a hybrid active push-prioritized prefetch strategy, which makes it highly resilient to rapid changes of disk state exhibited by I/O intensive workloads. At the same time, transparency ensures a maximum of portability with a wide range of hypervisors. Large scale experiments that involve multiple simultaneous migrations of both synthetic benchmarks and a real scientific application show improvements of up to 10x faster migration time, 5x less bandwidth consumption and 62% less performance degradation over state-of-art.
Robin Callister - One of the best experts on this subject based on the ideXlab platform.
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Evaluation of a commercial web-based weight loss and weight loss Maintenance program in overweight and obese adults: a randomized controlled trial
BMC Public Health, 2010Co-Authors: Clare E Collins, Philip J Morgan, Pennie Jones, Kate Fletcher, Julia Martin, Elroy J Aguiar, Ashlee Lucas, Melinda Neve, Patrick Mcelduff, Robin CallisterAbstract:Background Obesity rates in adults continue to rise and effective treatment programs with a broad reach are urgently required. This paper describes the study protocol for a web-based randomized controlled trial (RCT) of a commercially available program for overweight and obese adult males and females. The aim of this RCT was to determine and compare the efficacy of two web-based interventions for weight loss and Maintenance of lost weight. Methods/Design Overweight and obese adult males and females were stratified by gender and BMI and randomly assigned to one of three groups for 12-weeks: waitlist control, or basic or enhanced Online weight-loss. Control participants were re-randomized to the two weight loss groups at the end of the 12-week period. The basic and enhanced group participants had an option to continue or repeat the 12-week program. If the weight loss goal was achieved at the end of 12, otherwise on completion of 24 weeks of weight loss, participants were re-randomized to one of two Online Maintenance programs (Maintenance basic or Maintenance enhanced), until 18 months from commencing the weight loss program. Assessments took place at baseline, three, six, and 18 months after commencing the initial weight loss intervention with control participants repeating the initial assessment after three month of waiting. The primary outcome is body mass index (BMI). Other outcomes include weight, waist circumference, blood pressure, plasma markers of cardiovascular disease risk, dietary intake, eating behaviours, physical activity and quality of life. Both the weight loss and Maintenance of lost weight programs were based on social cognitive theory with participants advised to set goals, self-monitor weight, dietary intake and physical activity levels. The enhanced weight loss and Maintenance programs provided additional personalized, system-generated feedback on progress and use of the program. Details of the methodological aspects of recruitment, inclusion criteria, randomization, intervention programs, assessments and statistical analyses are described. Discussion Importantly, this paper describes how an RCT of a currently available commercial Online program in Australia addresses some of the short falls in the current literature pertaining to the efficacy of web-based weight loss programs. Australian New Zealand Clinical Trials Registry (ANZCTR) number: ACTRN12610000197033
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Evaluation of a commercial web-based weight loss and weight loss Maintenance program in overweight and obese adults: a randomized controlled trial
BMC public health, 2010Co-Authors: Clare E Collins, Philip J Morgan, Pennie Jones, Kate Fletcher, Julia Martin, Elroy J Aguiar, Ashlee Lucas, Melinda Neve, Patrick Mcelduff, Robin CallisterAbstract:Obesity rates in adults continue to rise and effective treatment programs with a broad reach are urgently required. This paper describes the study protocol for a web-based randomized controlled trial (RCT) of a commercially available program for overweight and obese adult males and females. The aim of this RCT was to determine and compare the efficacy of two web-based interventions for weight loss and Maintenance of lost weight. Overweight and obese adult males and females were stratified by gender and BMI and randomly assigned to one of three groups for 12-weeks: waitlist control, or basic or enhanced Online weight-loss. Control participants were re-randomized to the two weight loss groups at the end of the 12-week period. The basic and enhanced group participants had an option to continue or repeat the 12-week program. If the weight loss goal was achieved at the end of 12, otherwise on completion of 24 weeks of weight loss, participants were re-randomized to one of two Online Maintenance programs (Maintenance basic or Maintenance enhanced), until 18 months from commencing the weight loss program. Assessments took place at baseline, three, six, and 18 months after commencing the initial weight loss intervention with control participants repeating the initial assessment after three month of waiting. The primary outcome is body mass index (BMI). Other outcomes include weight, waist circumference, blood pressure, plasma markers of cardiovascular disease risk, dietary intake, eating behaviours, physical activity and quality of life.Both the weight loss and Maintenance of lost weight programs were based on social cognitive theory with participants advised to set goals, self-monitor weight, dietary intake and physical activity levels. The enhanced weight loss and Maintenance programs provided additional personalized, system-generated feedback on progress and use of the program. Details of the methodological aspects of recruitment, inclusion criteria, randomization, intervention programs, assessments and statistical analyses are described. Importantly, this paper describes how an RCT of a currently available commercial Online program in Australia addresses some of the short falls in the current literature pertaining to the efficacy of web-based weight loss programs.Australian New Zealand Clinical Trials Registry (ANZCTR) number: ACTRN12610000197033.
Wolfgang Bisle - One of the best experts on this subject based on the ideXlab platform.
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Content Adaptive Signal Compression for Remote SHM and NDT Operation
Structural Health Monitoring 2015, 2015Co-Authors: Marco Schaarschmidt, Clemens Westerkamp, Alexander Hennewig, Dennis Pieper, Holger Speckmann, Wolfgang BisleAbstract:Remote engineering systems are valuable tools to give visual assistance and remote support e.g. in Structural Health Monitoring (SHM) or Non-destructive Testing (NDT). They allow discussing a second opinion with a remote expert and thus reducing the human factor during testing and monitoring. For an optimal impression of the situation, the second person requires both a camera view of the location and the screen view of the SHM/NDT system used. The Online Maintenance Assistance (OMA) system implements this two-view collaboration. Remote partners can see and actively control measuring equipment, while observing details of the location in the camera window. Due to varying screen signals and communication properties, an adaption for optimal visual quality of the camera and screen signal compression is required. The adaption is performed in a Machine Learning System (MLS), which uses an adapted k-nearest neighbors algorithm to adapt signal compression parameters to the measurement task and the communication channel. doi: 10.12783/SHM2015/148
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An Online System for Remote SHM Operation with Content Adaptive Signal Compression
2014Co-Authors: Clemens Westerkamp, Alexander Hennewig, Holger Speckmann, Wolfgang Bisle, Nicolas Colin, Mona RafrafiAbstract:Remote engineering systems are valuable tools to give visual assistance and remote support e.g. in NDT (Non-destructive Testing) or SHM (Structural Health Monitoring). They allow discussing a second opinion with a remote expert and thus reducing the human factor during testing and monitoring. For an optimal impression of the situation, the second person requires both a camera view of the location and the screen view of the system used. The OMA system (Online Maintenance Assistance) implements this two-view collaboration. Remote partners can see and actively control the equipment, while observing details of the location in the camera window. Due to varying working conditions, screen signals and communication properties, an adaptive compression for both signals (camera and screen) is proposed. This permits to always maintain the best possible visual quality for the assessment performed by the remote partner. The OMA screen compression is valuable for dynamic signals like in most NDT applications. Slower NDT and SHM applications benefit from a smoother and more realistic handling of the controlled software. Currently compression profiles are switched manually, but a classificator will soon allow automatic adaptation. Since most of the OMA system is browser based, it can be used on laptops or tablets and will be available for the iOS based iPad soon. The compression benefits can be used for sensor data compression and direct sensor data communication as well. New OMA integrations include other testing technologies, devices and other and other signal related aspects. The authors are interested in other collaboration scenario with the neeed for multiple views on cameras and screens.
Clare E Collins - One of the best experts on this subject based on the ideXlab platform.
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Evaluation of a commercial web-based weight loss and weight loss Maintenance program in overweight and obese adults: a randomized controlled trial
BMC Public Health, 2010Co-Authors: Clare E Collins, Philip J Morgan, Pennie Jones, Kate Fletcher, Julia Martin, Elroy J Aguiar, Ashlee Lucas, Melinda Neve, Patrick Mcelduff, Robin CallisterAbstract:Background Obesity rates in adults continue to rise and effective treatment programs with a broad reach are urgently required. This paper describes the study protocol for a web-based randomized controlled trial (RCT) of a commercially available program for overweight and obese adult males and females. The aim of this RCT was to determine and compare the efficacy of two web-based interventions for weight loss and Maintenance of lost weight. Methods/Design Overweight and obese adult males and females were stratified by gender and BMI and randomly assigned to one of three groups for 12-weeks: waitlist control, or basic or enhanced Online weight-loss. Control participants were re-randomized to the two weight loss groups at the end of the 12-week period. The basic and enhanced group participants had an option to continue or repeat the 12-week program. If the weight loss goal was achieved at the end of 12, otherwise on completion of 24 weeks of weight loss, participants were re-randomized to one of two Online Maintenance programs (Maintenance basic or Maintenance enhanced), until 18 months from commencing the weight loss program. Assessments took place at baseline, three, six, and 18 months after commencing the initial weight loss intervention with control participants repeating the initial assessment after three month of waiting. The primary outcome is body mass index (BMI). Other outcomes include weight, waist circumference, blood pressure, plasma markers of cardiovascular disease risk, dietary intake, eating behaviours, physical activity and quality of life. Both the weight loss and Maintenance of lost weight programs were based on social cognitive theory with participants advised to set goals, self-monitor weight, dietary intake and physical activity levels. The enhanced weight loss and Maintenance programs provided additional personalized, system-generated feedback on progress and use of the program. Details of the methodological aspects of recruitment, inclusion criteria, randomization, intervention programs, assessments and statistical analyses are described. Discussion Importantly, this paper describes how an RCT of a currently available commercial Online program in Australia addresses some of the short falls in the current literature pertaining to the efficacy of web-based weight loss programs. Australian New Zealand Clinical Trials Registry (ANZCTR) number: ACTRN12610000197033
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Evaluation of a commercial web-based weight loss and weight loss Maintenance program in overweight and obese adults: a randomized controlled trial
BMC public health, 2010Co-Authors: Clare E Collins, Philip J Morgan, Pennie Jones, Kate Fletcher, Julia Martin, Elroy J Aguiar, Ashlee Lucas, Melinda Neve, Patrick Mcelduff, Robin CallisterAbstract:Obesity rates in adults continue to rise and effective treatment programs with a broad reach are urgently required. This paper describes the study protocol for a web-based randomized controlled trial (RCT) of a commercially available program for overweight and obese adult males and females. The aim of this RCT was to determine and compare the efficacy of two web-based interventions for weight loss and Maintenance of lost weight. Overweight and obese adult males and females were stratified by gender and BMI and randomly assigned to one of three groups for 12-weeks: waitlist control, or basic or enhanced Online weight-loss. Control participants were re-randomized to the two weight loss groups at the end of the 12-week period. The basic and enhanced group participants had an option to continue or repeat the 12-week program. If the weight loss goal was achieved at the end of 12, otherwise on completion of 24 weeks of weight loss, participants were re-randomized to one of two Online Maintenance programs (Maintenance basic or Maintenance enhanced), until 18 months from commencing the weight loss program. Assessments took place at baseline, three, six, and 18 months after commencing the initial weight loss intervention with control participants repeating the initial assessment after three month of waiting. The primary outcome is body mass index (BMI). Other outcomes include weight, waist circumference, blood pressure, plasma markers of cardiovascular disease risk, dietary intake, eating behaviours, physical activity and quality of life.Both the weight loss and Maintenance of lost weight programs were based on social cognitive theory with participants advised to set goals, self-monitor weight, dietary intake and physical activity levels. The enhanced weight loss and Maintenance programs provided additional personalized, system-generated feedback on progress and use of the program. Details of the methodological aspects of recruitment, inclusion criteria, randomization, intervention programs, assessments and statistical analyses are described. Importantly, this paper describes how an RCT of a currently available commercial Online program in Australia addresses some of the short falls in the current literature pertaining to the efficacy of web-based weight loss programs.Australian New Zealand Clinical Trials Registry (ANZCTR) number: ACTRN12610000197033.
