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Displaying 1-42 out of 42 total
Monitoring and analysing a Grid Middleware Node
Found in: Grid Computing, IEEE/ACM International Workshop on
By Ramon Nou, Ferran Julia, David Carrera, Kevin Hogan, Jordi Caubet, Jesus Labarta, Jordi Torres
Issue Date:September 2006
pp. 309-310
Distributed grid applications are becoming more and more popular as the use of complex grid middlewares becomes extensive, and more facilities are offered by these complex pieces of software. But as grid middlewares grow and offer more advanced features, t...
 
Optimal Resource Allocation in a Virtualized Software Aging Platform with Software Rejuvenation
Found in: Software Reliability Engineering, International Symposium on
By Javier Alonso,Ã?ñigo Goiri,Jordi Guitart,Ricard Gavaldà,Jordi Torres
Issue Date:December 2011
pp. 250-259
Nowadays, virtualized platforms have become the most popular option to deploy complex enough services. The reason is that virtualization allows resource providers to increase resource utilization. Deployed services are expected to be always available, but ...
 
Energy-Aware Scheduling in Virtualized Datacenters
Found in: Cluster Computing, IEEE International Conference on
By Ã?ñigo Goiri, Ferran Julià, Ramón Nou, Josep Ll. Berral, Jordi Guitart, Jordi Torres
Issue Date:September 2010
pp. 58-67
The reduction of energy consumption in large-scale datacenters is being accomplished through an extensive use of virtualization, which enables the consolidation of multiple workloads in a smaller number of machines. Nevertheless, virtualization also incurs...
 
Characterizing Cloud Federation for Enhancing Providers' Profit
Found in: Cloud Computing, IEEE International Conference on
By Ã?ñigo Goiri, Jordi Guitart, Jordi Torres
Issue Date:July 2010
pp. 123-130
Cloud federation has been proposed as a new paradigm that allows providers to avoid the limitation of owning only a restricted amount of resources, which forces them to reject new customers when they have not enough local resources to fulfill their custome...
 
Introducing Virtual Execution Environments for Application Lifecycle Management and SLA-Driven Resource Distribution within Service Providers
Found in: Network Computing and Applications, IEEE International Symposium on
By Iñigo Goiri, Ferran Julià, Jorge Ejarque, Marc de Palol, Rosa M. Badia, Jordi Guitart, Jordi Torres
Issue Date:July 2009
pp. 211-218
Resource management is a key challenge that service providers must adequately face in order to ensure their profitability. This paper describes a proof-of-concept framework for facilitating resource management in service providers, which allows reducing co...
 
SLA-Driven Semantically-Enhanced Dynamic Resource Allocator for Virtualized Service Providers
Found in: eScience, IEEE International Conference on
By Jorge Ejarque, Marc de Palol, Íñigo Goiri, Ferran Julià, Jordi Guitart, Rosa M. Badia, Jordi Torres
Issue Date:December 2008
pp. 8-15
In order to be profitable, service providers must be able to undertake complex management tasks such as provisioning, deployment, execution and adaptation in an autonomic way. This paper introduces a framework, the Semantically-Enhanced Resource Allocator ...
 
High-available grid services through the use of virtualized clustering
Found in: Grid Computing, IEEE/ACM International Workshop on
By Javier Alonso, Luis Silva, Artur Andrzejak, Paulo Silva, Jordi Torres
Issue Date:September 2007
pp. 34-41
Grid applications comprise several components and web-services that make them highly prone to the occurrence of transient software failures and aging problems. This type of failures often incur in undesired performance levels and unexpected partial crashes...
 
Session-Based Adaptive Overload Control for Secure Dynamic Web Applications
Found in: Parallel Processing, International Conference on
By Jordi Guitart, David Carrera, Vincenç Beltran, Jordi Torres, Eduard Ayguadé
Issue Date:June 2005
pp. 341-349
As dynamic web content and security capabilities are becoming popular in current web sites, the performance demand or application servers that host the sites is increasing, leading sometimes these servers to overload. As a result, response times may grow t...
 
Characterizing Secure Dynamic Web Applications Scalability
Found in: Parallel and Distributed Processing Symposium, International
By Jordi Guitart, Vicenç Beltran, David Carrera, Jordi Torres, Eduard Ayguadé
Issue Date:April 2005
pp. 108a
Security in the access to web contents and the interaction with web sites is becoming one of the most important issues in Internet. Servers need to provide certain levels of security so that the user feels comfortable when running the applications that pro...
 
Tuning Dynamic Web Applications using Fine-Grain Analysis
Found in: Parallel, Distributed, and Network-Based Processing, Euromicro Conference on
By Jordi Guitart, David Carrera, Jordi Torres, Eduard Ayguadé, Jesús Labarta
Issue Date:February 2005
pp. 84-91
In this paper we present a methodology to analyze the behavior and performance of Java application servers using a performance analysis framework. This framework considers all levels involved in the application server execution (application, server, virtua...
 
Application/Kernel Cooperation Towards the Efficient Execution of Shared-Memory Parallel Java Codes
Found in: Parallel and Distributed Processing Symposium, International
By Jordi Guitart, Xavier Martorell, Jordi Torres, Eduard Ayguadé
Issue Date:April 2003
pp. 38a
In this paper we propose mechanisms to improve the performance of parallel Java applications executing on multiprogrammed shared-memory multiprocessors. The proposal is based on a dialog between each Java application and the underlying execution environmen...
 
Performance Analysis Tools for Parallel Java Applications on Shared-Memory Systems
Found in: Parallel Processing, International Conference on
By Jordi Guitart, Jordi Torres, Eduard Ayguadé, J. Mark Bull
Issue Date:September 2001
pp. 0357
Abstract: In this paper we describe an instrumentation environment for the performance analysis and visualization of parallel applications written in JOMP, an OpenMP-like interface for Java. The environment includes two complementary approaches. The first ...
 
GreenSlot: scheduling energy consumption in green datacenters
Found in: SC Conference
By Ã?ñigo Goiri,Ryan Beauchea,Kien Le,Thu D. Nguyen,Md. E. Haque,Jordi Guitart,Jordi Torres,Ricardo Bianchini
Issue Date:November 2011
pp. 1-11
In this paper, we propose GreenSlot, a parallel batch job scheduler for a datacenter powered by a photovoltaic solar array and the electrical grid (as a backup). GreenSlot predicts the amount of solar energy that will be available in the near future, and s...
 
Intelligent Placement of Datacenters for Internet Services
Found in: Distributed Computing Systems, International Conference on
By Ã?ñigo Goiri, Kien Le, Jordi Guitart, Jordi Torres, Ricardo Bianchini
Issue Date:June 2011
pp. 131-142
Popular Internet services are hosted by multiple geographically distributed data centers. The location of the data centers has a direct impact on the services' response times, capital and operational costs, and (indirect) carbon dioxide emissions. Selectin...
 
Using Semantics for Resource Allocation in Computing Service Providers
Found in: Services Computing, IEEE International Conference on
By Jorge Ejarque, Marc de Palol, Inigo Goiri, Ferran Julia, Jordi Guitart, Jordi Torres, Rosa M. Badia
Issue Date:July 2008
pp. 583-587
Service providers (SP) business goals require an efficient management of their computational resources in order to perform provisioning, deployment, execution and adaptation which traditionally require human intervention. The Semantically-Enhanced Resource...
 
Tailoring Resources: The Energy Efficient Consolidation Strategy Goes Beyond Virtualization
Found in: Autonomic Computing, International Conference on
By Jordi Torres, David Carrera, Vicenç Beltran, Nicolás Poggi, Kevin Hogan, Josep Ll. Berral, Ricard Gavaldà, Eduard Ayguadé, Toni Moreno, Jordi Guitart
Issue Date:June 2008
pp. 197-198
Virtualization and consolidation are two complementary techniques widely adopted in a global strategy to reduce system management complexity. In this paper we show how two simple and well-known techniques can be combined to dramatically increase the energy...
 
Monitoring and Analysis Framework for Grid Middleware
Found in: Parallel, Distributed, and Network-Based Processing, Euromicro Conference on
By Ramon Nou, Ferran Julia, David Carrera, Kevin Hogan, Jordi Caubet, Jesus Labarta, Jordi Torres
Issue Date:February 2007
pp. 129-133
<p>As the use of complex grid middleware becomes widespread and more facilites are offered by these pieces of software, distributed Grid applications are becoming more and more popular. But as Grid middleware grows in size and offers more advanced fe...
 
Experiences with Simulations - A Light and Fast Model for Secure Web Applications
Found in: Parallel and Distributed Systems, International Conference on
By Ramon Nou, Jordi Guitart, David Carrera, Jordi Torres
Issue Date:July 2006
pp. 177-186
Using simulations of a complex system such as a Web Application Server provides us with a tool that allows the running of tests without using the resources needed in a real system; thus enabling a
 
Should the grid middleware look to self-managing capabilities?
Found in: Autonomous Decentralized Systems, International Symposium on
By Ramon Nou, Ferran Julià, Jordi Torres
Issue Date:March 2007
pp. 113-122
Grid technologies have enabled the clustering of a wide variety of geographically distributed resources and services. While providing this, the grid middleware layers that make up the supporting platform for grid applications have taken an increased level ...
 
Autonomic Placement of Mixed Batch and Transactional Workloads
Found in: IEEE Transactions on Parallel and Distributed Systems
By David Carrera,Malgorzata Steinder,Ian Whalley,Jordi Torres,Eduard Ayguadé
Issue Date:February 2012
pp. 219-231
To reduce the cost of infrastructure and electrical energy, enterprise datacenters consolidate workloads on the same physical hardware. Often, these workloads comprise both transactional and long-running analytic computations. Such consolidation brings new...
 
A Hybrid Web Server Architecture for e-Commerce Applications
Found in: Parallel and Distributed Systems, International Conference on
By David Carrera, Vicenc Beltran, Jordi Torres, Eduard Ayguade
Issue Date:July 2005
pp. 182-188
<p>The performance of an e-commerce application can be measured according to technical metrics but also following business indicators. The revenue obtained by a commercial web application is directly related to the amount of clients that complete bus...
 
WAS Control Center: An Autonomic Performance-Triggered Tracing Environment for WebSphere
Found in: Parallel, Distributed, and Network-Based Processing, Euromicro Conference on
By David Carrera, David Garcia, Jordi Torres, Eduard Ayguadé, Jesús Labarta
Issue Date:February 2005
pp. 26-32
Studying any aspect of an application server with high availability requirements can become a tedious task when a continuous monitoring of the server status is necessary. The creation of performance-driven autonomic systems can hurry up the analysis of thi...
 
Evaluating the Scalability of Java Event-Driven Web Servers
Found in: Parallel Processing, International Conference on
By Vicenç Beltran, David Carrera, Jordi Torres, Eduard Ayguadé
Issue Date:August 2004
pp. 134-142
The two major strategies used to construct high-performance web servers are thread pools and event-driven architectures. The Java platform is commonly used in web environments but up to the moment it did not provide any standard API to implement event-driv...
 
Power-Aware Multi-data Center Management Using Machine Learning
Found in: 2013 42nd International Conference on Parallel Processing (ICPP)
By Josep Ll Berral,Ricard Gavalda,Jordi Torres
Issue Date:October 2013
pp. 858-867
The cloud relies upon multi-data center (multi-DC) infrastructures distributed along the world, where people and enterprises pay for resources to offer their web-services to worldwide clients. Intelligent management is required to automate and manage these...
 
Enabling Distributed Key-Value Stores with Low Latency-Impact Snapshot Support
Found in: 2013 IEEE 12th International Symposium on Network Computing and Applications (NCA)
By Jorda Polo,Yolanda Becerra,David Carrera,Jordi Torres,Eduard Ayguade,Mike Spreitzer,Malgorzata Steinder
Issue Date:August 2013
pp. 65-72
Current distributed key-value stores generally provide greater scalability at the expense of weaker consistency and isolation. However, additional isolation support is becoming increasingly important in the environments in which these stores are deployed, ...
 
Adaptive Scheduling on Power-Aware Managed Data-Centers Using Machine Learning
Found in: Grid Computing, IEEE/ACM International Workshop on
By Josep Ll. Berral,Ricard Gavaldà,Jordi Torres
Issue Date:September 2011
pp. 66-73
Energy-related costs have become one of the major economic factors in IT data-centers, and companies and the research community are currently working on new efficient power-aware resource management strategies, also known as
 
Performance Management of Accelerated MapReduce Workloads in Heterogeneous Clusters
Found in: Parallel Processing, International Conference on
By Jordà Polo, David Carrera, Yolanda Becerra, Vicenç Beltran, Jordi Torres, Eduard Ayguadé
Issue Date:September 2010
pp. 653-662
Next generation data centers will be composed of thousands of hybrid systems in an attempt to increase overall cluster performance and to minimize energy consumption. New programming models, such as MapReduce, specifically designed to make the most of very...
 
Adaptive on-line software aging prediction based on machine learning
Found in: Dependable Systems and Networks, International Conference on
By Javier Alonso, Jordi Torres, Josep Ll. Berral, Ricard Gavalda
Issue Date:July 2010
pp. 507-516
The growing complexity of software systems is resulting in an increasing number of software faults. According to the literature, software faults are becoming one of the main sources of unplanned system outages, and have an important impact on company benef...
 
J2EE instrumentation for software aging root cause application component determination with AspectJ
Found in: Parallel and Distributed Processing Workshops and PhD Forum, 2011 IEEE International Symposium on
By Javier Alonso,Jordi Torres,Josep Ll. Berral,Ricard Gavalda
Issue Date:April 2010
pp. 1-8
Unplanned system outages have a negative impact on company revenues and image. While the last decades have seen a lot of efforts from industry and academia to avoid them, they still happen and their impact is increasing. According to many studies, one of t...
 
Using Virtualization to Improve Software Rejuvenation
Found in: IEEE Transactions on Computers
By Luis Moura Silva, Javier Alonso, Jordi Torres
Issue Date:November 2009
pp. 1525-1538
In this paper, we present an approach for software rejuvenation based on automated self-healing techniques that can be easily applied to off-the-shelf Application Servers. Software aging and transient failures are detected through continuous monitoring of ...
 
Heterogeneous QoS Resource Manager with Prediction
Found in: Autonomic and Autonomous Systems, International Conference on
By Ramon Nou, Jordi Torres
Issue Date:April 2009
pp. 69-74
As long as computers continue to get more CPU processing power, data centers need to optimize their power usage. We can do this and maintain the same complexity level as before by using virtualized environments. We can put a large number of small isolated ...
 
Predicting Web Server Crashes: A Case Study in Comparing Prediction Algorithms
Found in: Autonomic and Autonomous Systems, International Conference on
By Javier Alonso, Jordi Torres, Ricard Gavaldà
Issue Date:April 2009
pp. 264-269
Traditionally, performance has been the most important metrics when evaluating a system. However, in the last decades industry and academia have been paying increasing attention to another metric to evaluate servers: availability. A web server may serve ma...
 
Work in Progress: Building a Distributed Generic Stress Tool for Server Performance and Behavior Analysis
Found in: Autonomic and Autonomous Systems, International Conference on
By Ada Casanovas, Javier Alonso, Jordi Torres, Artur Andrzejak
Issue Date:April 2009
pp. 342-345
One of the primary tools for performance analysis of multi-tier systems are standardized
 
Improving Web Server Performance Through Main Memory Compression
Found in: Parallel and Distributed Systems, International Conference on
By Vicenç Beltran, Jordi Torres, Eduard Ayguadé
Issue Date:December 2008
pp. 303-310
Current web servers are highly multithreaded applications whose scalability benefits from the current multi-core/multiprocessor trend. However, some workloads cannot capitalize on this because their performance is limited by the available memory and/or the...
 
Understanding tuning complexity in multithreaded and hybrid web servers
Found in: Parallel and Distributed Processing Symposium, International
By Vicenc Beltran, Jordi Torres, Eduard Ayguade
Issue Date:April 2008
pp. 1-12
Adequately setting up a multi-threaded web server is a challenging task because its performance is determined by a combination of configurable web server parameters and unsteady external factors like the workload type, workload intensity and machine resour...
 
Reducing wasted resources to help achieve green data centers
Found in: Parallel and Distributed Processing Symposium, International
By Jordi Torres, David Carrera, Kevin Hogan, Ricard Gavalda, Vicenc Beltran, Nicolas Poggi
Issue Date:April 2008
pp. 1-8
In this paper we introduce a new approach to the consolidation strategy of a data center that allows an important reduction in the amount of active nodes required to process a heterogeneous workload without degrading the offered service level. This article...
 
Using Virtualization to Improve Software Rejuvenation
Found in: Network Computing and Applications, IEEE International Symposium on
By Luis Moura Silva, Javier Alonso, Paulo Silva, Jordi Torres, Artur Andrzejak
Issue Date:July 2007
pp. 33-44
In this paper, we present an approach for software rejuvenation based on automated self-healing techniques that can be easily applied to off-the-shelf Application Servers and Internet sites. Software aging and transient failures are detected through contin...
 
The need for self-managed access nodes in grid environments.
Found in: Engineering of Autonomic and Autonomous Systems, IEEE International Workshop on
By Ramon Nou, Ferran Julia, Jordi Torres
Issue Date:March 2007
pp. 5-13
The Grid is constantly growing and it is being used by more and more applications. In this scenario the entry node is an important component in the whole architecture and will become a contention point. In this paper we will demonstrate that the use of a s...
 
Adaptive MapReduce Scheduling in Shared Environments
Found in: 2014 14th IEEE/ACM International Symposium on Cluster, Cloud and Grid Computing (CCGrid)
By Jorda Polo,Yolanda Becerra,David Carrera,Jordi Torres,Eduard Ayguade,Malgorzata Steinder
Issue Date:May 2014
pp. 61-70
In this paper we present a MapReduce task scheduler for shared environments in which MapReduce is executed along with other resource-consuming workloads, such as transactional applications. All workloads may potentially share the same data store, some of t...
 
GreenHadoop: leveraging green energy in data-processing frameworks
Found in: Proceedings of the 7th ACM european conference on Computer Systems (EuroSys '12)
By Jordi Guitart, Jordi Torres, Kien Le, Ricardo Bianchini, Inigo Goiri, Thu D. Nguyen
Issue Date:April 2012
pp. 57-70
Interest has been growing in powering datacenters (at least partially) with renewable or "green" sources of energy, such as solar or wind. However, it is challenging to use these sources because, unlike the "brown" (carbon-intensive) energy drawn from the ...
     
Empowering automatic data-center management with machine learning
Found in: Proceedings of the 28th Annual ACM Symposium on Applied Computing (SAC '13)
By Jordi Torres, Josep Ll. Berral, Ricard Gavaldà
Issue Date:March 2013
pp. 170-172
The Cloud as computing paradigm has become nowadays crucial for most Internet business models. Managing and optimizing its performance on a moment-by-moment basis is not easy given as the amount and diversity of elements involved (hardware, applications, w...
     
Managing SLAs of heterogeneous workloads using dynamic application placement
Found in: Proceedings of the 17th international symposium on High performance distributed computing (HPDC '08)
By David Carrera, Eduard Ayguade, Ian Whalley, Jordi Torres, Malgorzata Steinder
Issue Date:June 2008
pp. 227-269
In this paper we address the problem of managing heterogeneous workloads in a virtualized data center. We consider two different workloads: transactional applications and long-running jobs. We present a technique that permits collocation of these workload ...
     
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