5 research outputs found
Cross-Layer Cloud Performance Monitoring, Analysis and Recovery
The basic idea of Cloud computing is to offer software and hardware resources as services. These services are provided at
different layers: Software (Software
as a Service: SaaS), Platform (Platform as a Service: PaaS) and Infrastructure
(Infrastructure as a Service: IaaS).
In such a complex environment, performance issues are quite likely and rather the norm than the exception.
Consequently, performance-related problems may frequently occur at all layers. Thus, it is necessary to monitor all Cloud layers and analyze their performance parameters to detect and rectify related problems.
This thesis presents a novel cross-layer reactive performance monitoring approach for Cloud computing environments, based on the methodology of Complex Event Processing (CEP). The proposed approach is called CEP4Cloud. It analyzes monitored events to detect performance-related problems and performs actions to fix them. The proposal is based on the use of (1) a novel multi-layer monitoring approach, (2) a new cross-layer analysis approach and (3) a novel recovery approach.
The proposed monitoring approach operates at all Cloud layers, while collecting related parameters. It makes use of existing monitoring tools and a new monitoring approach for Cloud services at the SaaS layer. The proposed SaaS monitoring approach is called AOP4CSM. It is based on aspect-oriented programming and monitors quality-of-service
parameters of the SaaS layer in a non-invasive manner. AOP4CSM neither modifies the server implementation nor the client
implementation.
The defined cross-layer analysis approach is called D-CEP4CMA. It is based on the methodology of Complex Event Processing (CEP). Instead of having to manually specify continuous queries on monitored event streams, CEP queries are derived from analyzing the correlations between monitored metrics across multiple Cloud layers. The results of the correlation analysis allow us to reduce the number of monitored parameters and enable us to perform a root cause analysis to identify the causes of performance-related problems. The derived analysis rules are implemented as queries in a CEP engine. D-CEP4CMA is designed to dynamically switch between different centralized and distributed CEP architectures depending on the load/memory of the CEP machine and network traffic conditions in the observed Cloud environment.
The proposed recovery approach is based on a novel action manager framework. It applies recovery actions at all Cloud layers. The novel action manager framework assigns a set of repair actions to each performance-related problem and checks the success of the applied action.
The results of several experiments illustrate the merits of the reactive performance monitoring approach and its main components (i.e., monitoring, analysis and recovery). First, experimental results show the efficiency of AOP4CSM (very low overhead).
Second, obtained results demonstrate the benefits of the analysis approach in terms of precision and recall compared to threshold-based methods. They also show the accuracy of the analysis approach in identifying the causes of performance-related problems. Furthermore, experiments illustrate the efficiency of D-CEP4CMA and its performance in terms of precision and recall compared to centralized and distributed CEP architectures.
Moreover, experimental results indicate that the time needed to fix a performance-related problem is reasonably short. They also show that the CPU overhead of using CEP4Cloud is negligible. Finally, experimental results demonstrate the merits of CEP4Cloud in terms of speeding up the repair and reducing the number of triggered alarms compared to baseline methods
DiffECG: A Generalized Probabilistic Diffusion Model for ECG Signals Synthesis
In recent years, deep generative models have gained attention as a promising
data augmentation solution for heart disease detection using deep learning
approaches applied to ECG signals. In this paper, we introduce a novel approach
based on denoising diffusion probabilistic models for ECG synthesis that covers
three scenarios: heartbeat generation, partial signal completion, and full
heartbeat forecasting. Our approach represents the first generalized
conditional approach for ECG synthesis, and our experimental results
demonstrate its effectiveness for various ECG-related tasks. Moreover, we show
that our approach outperforms other state-of-the-art ECG generative models and
can enhance the performance of state-of-the-art classifiers.Comment: under revie
Leveraging Statistical Shape Priors in GAN-based ECG Synthesis
Due to the difficulty of collecting electrocardiogram (ECG) data during
emergency situations, ECG data generation is an efficient solution for dealing
with highly imbalanced ECG training datasets. However, due to the complex
dynamics of ECG signals, the synthesis of such signals is a challenging task.
In this paper, we present a novel approach for ECG signal generation based on
Generative Adversarial Networks (GANs). Our approach combines GANs with
statistical ECG data modeling to leverage prior knowledge about ECG dynamics in
the generation process. To validate the proposed approach, we present
experiments using ECG signals from the MIT-BIH arrhythmia database. The
obtained results show the benefits of modeling temporal and amplitude
variations of ECG signals as 2-D shapes in generating realistic signals and
also improving the performance of state-of-the-art arrhythmia classification
baselines.Comment: 6 figures, 26 page
Cross-Layer Cloud Performance Monitoring, Analysis and Recovery
The basic idea of Cloud computing is to offer software and hardware resources as services. These services are provided at different layers: Software (Software as a Service: SaaS), Platform (Platform as a Service: PaaS) and Infrastructure (Infrastructure as a Service: IaaS). In such a complex environment, performance issues are quite likely and rather the norm than the exception. Consequently, performance-related problems may frequently occur at all layers. Thus, it is necessary to monitor all Cloud layers and analyze their performance parameters to detect and rectify related problems. This thesis presents a novel cross-layer reactive performance monitoring approach for Cloud computing environments, based on the methodology of Complex Event Processing (CEP). The proposed approach is called CEP4Cloud. It analyzes monitored events to detect performance-related problems and performs actions to fix them. The proposal is based on the use of (1) a novel multi-layer monitoring approach, (2) a new cross-layer analysis approach and (3) a novel recovery approach. The proposed monitoring approach operates at all Cloud layers, while collecting related parameters. It makes use of existing monitoring tools and a new monitoring approach for Cloud services at the SaaS layer. The proposed SaaS monitoring approach is called AOP4CSM. It is based on aspect-oriented programming and monitors quality-of-service parameters of the SaaS layer in a non-invasive manner. AOP4CSM neither modifies the server implementation nor the client implementation. The defined cross-layer analysis approach is called D-CEP4CMA. It is based on the methodology of Complex Event Processing (CEP). Instead of having to manually specify continuous queries on monitored event streams, CEP queries are derived from analyzing the correlations between monitored metrics across multiple Cloud layers. The results of the correlation analysis allow us to reduce the number of monitored parameters and enable us to perform a root cause analysis to identify the causes of performance-related problems. The derived analysis rules are implemented as queries in a CEP engine. D-CEP4CMA is designed to dynamically switch between different centralized and distributed CEP architectures depending on the load/memory of the CEP machine and network traffic conditions in the observed Cloud environment. The proposed recovery approach is based on a novel action manager framework. It applies recovery actions at all Cloud layers. The novel action manager framework assigns a set of repair actions to each performance-related problem and checks the success of the applied action. The results of several experiments illustrate the merits of the reactive performance monitoring approach and its main components (i.e., monitoring, analysis and recovery). First, experimental results show the efficiency of AOP4CSM (very low overhead). Second, obtained results demonstrate the benefits of the analysis approach in terms of precision and recall compared to threshold-based methods. They also show the accuracy of the analysis approach in identifying the causes of performance-related problems. Furthermore, experiments illustrate the efficiency of D-CEP4CMA and its performance in terms of precision and recall compared to centralized and distributed CEP architectures. Moreover, experimental results indicate that the time needed to fix a performance-related problem is reasonably short. They also show that the CPU overhead of using CEP4Cloud is negligible. Finally, experimental results demonstrate the merits of CEP4Cloud in terms of speeding up the repair and reducing the number of triggered alarms compared to baseline methods