Albino Aveleda - Academia.edu (original) (raw)

Papers by Albino Aveleda

Research paper thumbnail of ParGRES: a middleware for executing OLAP queries in parallel". In: COPPE/UFRJ

ParGRES is a middleware aimed to efficiently process heavy weight queries, typical of OLAP, on to... more ParGRES is a middleware aimed to efficiently process heavy weight queries, typical of OLAP, on top of a database cluster. ParGRES achieves query processing speed-up through intra-and inter-query parallelism in a PC cluster environment with database replication and virtual partitioning. It accelerates both individual queries and system throughput. Our experimental results show that ParGRES yields super-linear or near-linear speed-up. ParGRES middleware keeps application and database autonomy. As a result, it offers a non-intrusive migration solution from sequential to a parallel environment. Currently, ParGRES uses PostgreSQL, but it is not DBMS dependent, and has a Web administration tool. The main features of ParGRES are: automatic parsing of SQL queries to allow for intra-query parallel execution; query processing with inter-and intra-query parallelism; virtual dynamic partition definition; result composition; update processing; and dynamic load balancing. The main contribution of ParGRES is to combine inter and intra-query parallelism with dynamic load balancing for virtual partitions, all within an open source cost-effective solution.

Research paper thumbnail of HPC Environment Management: New Challenges in the Petaflop Era

Lecture Notes in Computer Science, 2011

High Performance Computing (HPC) is becoming much more popular nowadays. Currently, the biggest s... more High Performance Computing (HPC) is becoming much more popular nowadays. Currently, the biggest supercomputers in the world have hundreds of thousands of processors and consequently may have more software and hardware failures. HPC centers managers also have to deal with multiple clusters from different vendors with their particular architectures. However, since there are not enough HPC experts to manage all the new supercomputers, it is expected that non-experts will be managing those large clusters. In this paper we study the new challenges to manage HPC environments containing different clusters with different sizes and architectures. We review available tools and present LEMMing [1], an easy-to-use open source tool developed to support high performance computing centers. LEMMing integrates machine resources and the available management and monitoring tools on a single point of management.

Research paper thumbnail of Performance comparison of scientific applications on Cray architectures

The TOP500 project ranks the 500 th . most powerful computer systems in the world. This rank is b... more The TOP500 project ranks the 500 th . most powerful computer systems in the world. This rank is based on High-Performance LINPACK (HPL), a portable implementation of the LINPACK benchmark for distributed-memory computers. According to the TOP500's list published in June, 2010, most of the systems are Linux based clusters. However, the number of Windows based systems tends to grow in the next lists. In this paper the performance of a Linux and a Windows HPC Server cluster using the same hardware and scientific applications is evaluated. To assess performance, the HPL and NAS Parallel Benchmarks (NPB), as well as a real-world multi-physics application, named EdgeCFD, are used. This application is developed at NACAD-COPPE/UFRJ and it is an implicit edge-based coupled fluid flow and transport solver for large-scale problems optimized for modern clusters. EdgeCFD adopts peer-to-peer non-blocking communication pattern among processes. Tests were conducted for three MPI distributions MVAPICH2 (based on MPICH2 with Infiniband support), OpenMPI (High Performance Message Passing Library) and MS-MPI (Microsoft MPI based on MPICH2) on all benchmarks and applications of this study. All performance measurements show that Windows HPC Server is a viable option.

Research paper thumbnail of Integrating solution engines under a distributed processing environment: An alternative approach for static and dynamic security assessment of large scale power systems

2014 IEEE PES General Meeting | Conference & Exposition, 2014

Research paper thumbnail of Evaluation of Message Passing Communication Patterns in Finite Element Solution of Coupled Problems

Lecture Notes in Computer Science, 2011

This work presents a performance evaluation of single node and subdomain communication schemes av... more This work presents a performance evaluation of single node and subdomain communication schemes available in EdgeCFD, an implicit edgebased coupled fluid flow and transport code for solving large scale problems in modern clusters. A natural convection flow problem is considered to assess performance metrics. Tests, focused in single node multi-core performance, show that past Intel Xeon processors dramatically suffer when large workloads are imposed to a single node. However, the problem seems to be mitigated in the newest Intel Xeon processor. We also observe that MPI non-blocking pointto-point interface sub-domain communications, although more difficult to implement, are more effective than collective interface sub-domain communications. enhance scalability by reducing communication overhead. The Computational Fluid Dynamics (CFD) community is aware of these new developments .

Research paper thumbnail of ParGRES: uma camada de processamento paralelo de consultas sobre o PostgreSQL

ParGRES aims at the development of free software to efficiently process heavy weight queries invo... more ParGRES aims at the development of free software to efficiently process heavy weight queries involving large databases by using PostgreSQL DBMS on top of PC clusters. ParGRES is a middleware based on intra-and inter parallel query processing and uses database replication combined with virtual fragmentation.

Research paper thumbnail of ParGRES: Middleware para Processamento Paralelo de Consultas OLAP em Clusters de Banco de Dados

This paper describes ParGRES, a software for parallel processing of OLAP queries on top of databa... more This paper describes ParGRES, a software for parallel processing of OLAP queries on top of database clusters. ParGRES is a middleware between the application and the database tiers that provides transparent access from the application to the parallel environment. Query processing in ParGRES combines intra-and inter-query parallelism techniques, while using database replication and virtual fragmentation. Resumo. Este artigo descreve o ParGRES, um software que tem como objetivo possibilitar o processamento paralelo de consultas OLAP sobre um cluster de banco de dados. ParGRES funciona como um middleware entre a camada da aplicação OLAP e a camada de banco de dados, tornando o processamento paralelo transparente à aplicação. O processamento das consultas explora o paralelismo intra-e inter-consultas, usando replicação e fragmentação virtual de dados.

Research paper thumbnail of ParGRES: a middleware for executing OLAP queries in parallel

ParGRES is a middleware aimed to efficiently process heavy weight queries, typical of OLAP, on to... more ParGRES is a middleware aimed to efficiently process heavy weight queries, typical of OLAP, on top of a database cluster. ParGRES achieves query processing speed-up through intra-and inter-query parallelism in a PC cluster environment with database replication and virtual partitioning. It accelerates both individual queries and system throughput. Our experimental results show that ParGRES yields super-linear or near-linear speed-up. ParGRES middleware keeps application and database autonomy. As a result, it offers a non-intrusive migration solution from sequential to a parallel environment. Currently, ParGRES uses PostgreSQL, but it is not DBMS dependent, and has a Web administration tool. The main features of ParGRES are: automatic parsing of SQL queries to allow for intra-query parallel execution; query processing with inter-and intra-query parallelism; virtual dynamic partition definition; result composition; update processing; and dynamic load balancing. The main contribution of ParGRES is to combine inter and intra-query parallelism with dynamic load balancing for virtual partitions, all within an open source cost-effective solution.

Research paper thumbnail of Evaluation of Parallel and Communication Models in the Finite Element Solution of Coupled Viscous Flow and Transport Problems

This work presents a performance evaluation of single node performance and subdomain communicatio... more This work presents a performance evaluation of single node performance and subdomain communication schemes available in EdgeCFD, an implicit edge-based coupled fluid flow and transport code for solving large scale problems in modern clusters, supporting stabilized and variational multiscale finite element formulations. A natural convection flow test problem is shown to assess performance metrics. Tests focused on single node multi-core performance show those previous versions of the Intel Xeon processors dramatically suffer when large workloads are imposed to a single node. However, the problem seems to be mitigated in the newest Intel Xeon processor. We also observe that MPI non-blocking pointto-point interface sub-domain communications, although more difficult to implement, are more effective than collective interface sub-domain communications.

Research paper thumbnail of ParGRES: a middleware for executing OLAP queries in parallel". In: COPPE/UFRJ

ParGRES is a middleware aimed to efficiently process heavy weight queries, typical of OLAP, on to... more ParGRES is a middleware aimed to efficiently process heavy weight queries, typical of OLAP, on top of a database cluster. ParGRES achieves query processing speed-up through intra-and inter-query parallelism in a PC cluster environment with database replication and virtual partitioning. It accelerates both individual queries and system throughput. Our experimental results show that ParGRES yields super-linear or near-linear speed-up. ParGRES middleware keeps application and database autonomy. As a result, it offers a non-intrusive migration solution from sequential to a parallel environment. Currently, ParGRES uses PostgreSQL, but it is not DBMS dependent, and has a Web administration tool. The main features of ParGRES are: automatic parsing of SQL queries to allow for intra-query parallel execution; query processing with inter-and intra-query parallelism; virtual dynamic partition definition; result composition; update processing; and dynamic load balancing. The main contribution of ParGRES is to combine inter and intra-query parallelism with dynamic load balancing for virtual partitions, all within an open source cost-effective solution.

Research paper thumbnail of HPC Environment Management: New Challenges in the Petaflop Era

Lecture Notes in Computer Science, 2011

High Performance Computing (HPC) is becoming much more popular nowadays. Currently, the biggest s... more High Performance Computing (HPC) is becoming much more popular nowadays. Currently, the biggest supercomputers in the world have hundreds of thousands of processors and consequently may have more software and hardware failures. HPC centers managers also have to deal with multiple clusters from different vendors with their particular architectures. However, since there are not enough HPC experts to manage all the new supercomputers, it is expected that non-experts will be managing those large clusters. In this paper we study the new challenges to manage HPC environments containing different clusters with different sizes and architectures. We review available tools and present LEMMing [1], an easy-to-use open source tool developed to support high performance computing centers. LEMMing integrates machine resources and the available management and monitoring tools on a single point of management.

Research paper thumbnail of Performance comparison of scientific applications on Cray architectures

The TOP500 project ranks the 500 th . most powerful computer systems in the world. This rank is b... more The TOP500 project ranks the 500 th . most powerful computer systems in the world. This rank is based on High-Performance LINPACK (HPL), a portable implementation of the LINPACK benchmark for distributed-memory computers. According to the TOP500's list published in June, 2010, most of the systems are Linux based clusters. However, the number of Windows based systems tends to grow in the next lists. In this paper the performance of a Linux and a Windows HPC Server cluster using the same hardware and scientific applications is evaluated. To assess performance, the HPL and NAS Parallel Benchmarks (NPB), as well as a real-world multi-physics application, named EdgeCFD, are used. This application is developed at NACAD-COPPE/UFRJ and it is an implicit edge-based coupled fluid flow and transport solver for large-scale problems optimized for modern clusters. EdgeCFD adopts peer-to-peer non-blocking communication pattern among processes. Tests were conducted for three MPI distributions MVAPICH2 (based on MPICH2 with Infiniband support), OpenMPI (High Performance Message Passing Library) and MS-MPI (Microsoft MPI based on MPICH2) on all benchmarks and applications of this study. All performance measurements show that Windows HPC Server is a viable option.

Research paper thumbnail of Integrating solution engines under a distributed processing environment: An alternative approach for static and dynamic security assessment of large scale power systems

2014 IEEE PES General Meeting | Conference & Exposition, 2014

Research paper thumbnail of Evaluation of Message Passing Communication Patterns in Finite Element Solution of Coupled Problems

Lecture Notes in Computer Science, 2011

This work presents a performance evaluation of single node and subdomain communication schemes av... more This work presents a performance evaluation of single node and subdomain communication schemes available in EdgeCFD, an implicit edgebased coupled fluid flow and transport code for solving large scale problems in modern clusters. A natural convection flow problem is considered to assess performance metrics. Tests, focused in single node multi-core performance, show that past Intel Xeon processors dramatically suffer when large workloads are imposed to a single node. However, the problem seems to be mitigated in the newest Intel Xeon processor. We also observe that MPI non-blocking pointto-point interface sub-domain communications, although more difficult to implement, are more effective than collective interface sub-domain communications. enhance scalability by reducing communication overhead. The Computational Fluid Dynamics (CFD) community is aware of these new developments .

Research paper thumbnail of ParGRES: uma camada de processamento paralelo de consultas sobre o PostgreSQL

ParGRES aims at the development of free software to efficiently process heavy weight queries invo... more ParGRES aims at the development of free software to efficiently process heavy weight queries involving large databases by using PostgreSQL DBMS on top of PC clusters. ParGRES is a middleware based on intra-and inter parallel query processing and uses database replication combined with virtual fragmentation.

Research paper thumbnail of ParGRES: Middleware para Processamento Paralelo de Consultas OLAP em Clusters de Banco de Dados

This paper describes ParGRES, a software for parallel processing of OLAP queries on top of databa... more This paper describes ParGRES, a software for parallel processing of OLAP queries on top of database clusters. ParGRES is a middleware between the application and the database tiers that provides transparent access from the application to the parallel environment. Query processing in ParGRES combines intra-and inter-query parallelism techniques, while using database replication and virtual fragmentation. Resumo. Este artigo descreve o ParGRES, um software que tem como objetivo possibilitar o processamento paralelo de consultas OLAP sobre um cluster de banco de dados. ParGRES funciona como um middleware entre a camada da aplicação OLAP e a camada de banco de dados, tornando o processamento paralelo transparente à aplicação. O processamento das consultas explora o paralelismo intra-e inter-consultas, usando replicação e fragmentação virtual de dados.

Research paper thumbnail of ParGRES: a middleware for executing OLAP queries in parallel

ParGRES is a middleware aimed to efficiently process heavy weight queries, typical of OLAP, on to... more ParGRES is a middleware aimed to efficiently process heavy weight queries, typical of OLAP, on top of a database cluster. ParGRES achieves query processing speed-up through intra-and inter-query parallelism in a PC cluster environment with database replication and virtual partitioning. It accelerates both individual queries and system throughput. Our experimental results show that ParGRES yields super-linear or near-linear speed-up. ParGRES middleware keeps application and database autonomy. As a result, it offers a non-intrusive migration solution from sequential to a parallel environment. Currently, ParGRES uses PostgreSQL, but it is not DBMS dependent, and has a Web administration tool. The main features of ParGRES are: automatic parsing of SQL queries to allow for intra-query parallel execution; query processing with inter-and intra-query parallelism; virtual dynamic partition definition; result composition; update processing; and dynamic load balancing. The main contribution of ParGRES is to combine inter and intra-query parallelism with dynamic load balancing for virtual partitions, all within an open source cost-effective solution.

Research paper thumbnail of Evaluation of Parallel and Communication Models in the Finite Element Solution of Coupled Viscous Flow and Transport Problems

This work presents a performance evaluation of single node performance and subdomain communicatio... more This work presents a performance evaluation of single node performance and subdomain communication schemes available in EdgeCFD, an implicit edge-based coupled fluid flow and transport code for solving large scale problems in modern clusters, supporting stabilized and variational multiscale finite element formulations. A natural convection flow test problem is shown to assess performance metrics. Tests focused on single node multi-core performance show those previous versions of the Intel Xeon processors dramatically suffer when large workloads are imposed to a single node. However, the problem seems to be mitigated in the newest Intel Xeon processor. We also observe that MPI non-blocking pointto-point interface sub-domain communications, although more difficult to implement, are more effective than collective interface sub-domain communications.