Now showing items 21-38 of 38

    • Improving web server performance through main memory compression 

      Beltran Querol, Vicenç; Torres Viñals, Jordi; Ayguadé Parra, Eduard (IEEE Computer Society, 2008)
      Conference lecture
      Open Access
      Current web servers are highly multithreaded applications whose scalability benefits from the current multicore/multiprocessor trend. However, some workloads can not capitalize on this because their performance is limited by ...
    • Introducing the Task-Aware Storage I/O (TASIO) Library 

      Roca Nonell, Aleix; Beltran Querol, Vicenç; Mateo Bellido, Sergi (Springer, 2019-08-09)
      Part of book or chapter of book
      Open Access
      Task-based programming models are excellent tools to parallelize and seamlessly load balance an application workload. However, the integration of I/O intensive applications and task-based programming models is lacking. ...
    • Leveraging OmpSs to exploit hardware accelerators 

      Sainz, Florentino; Mateo Bellido, Sergi; Beltran Querol, Vicenç; Bosque, José L.; Martorell Bofill, Xavier; Ayguadé Parra, Eduard (Institute of Electrical and Electronics Engineers (IEEE), 2014)
      Conference report
      Restricted access - publisher's policy
      CUDA and OpenCL are the most widely used programming models to exploit hardware accelerators. Both programming models provide a C-based programming language to write accelerator kernels and a host API used to glue the host ...
    • On the adequacy of lightweight thread approaches for high-level parallel programming models 

      Castelló, Adrián; Mayo Gual, Rafael; Sala Penadés, Kevin; Beltran Querol, Vicenç; Balaji, Pavan; Peña, Antonio J. (Elsevier, 2018-07)
      Article
      Open Access
      High-level parallel programming models (PMs) are becoming crucial in order to extract the computational power of current on-node multi-threaded parallelism. The most popular PMs, such as OpenMP or OmpSs, are directive-based: ...
    • On the applicability of PEBS based online memory access tracking for heterogeneous memory management at scale 

      Roca Nonell, Aleix; Gerofi, Balazs; Bautista-Gomez, Leonardo; Martinet, Dominique; Beltran Querol, Vicenç; Ishikawa, Yutaka (Association for Computing Machinery (ACM), 2018-11)
      Conference lecture
      Open Access
      Operating systems have historically had to manage only a single type of memory device. The imminent availability of heterogeneous memory devices based on emerging memory technologies confronts the classic single memory ...
    • Optimizing resource utilization with software-based temporal multi-threading (sTMT) 

      Beltran Querol, Vicenç; Ayguadé Parra, Eduard (2013)
      Conference report
      Restricted access - publisher's policy
      Compute and memory access units are two of the most important resources to appropriately manage in current and future multi–/many–core architectures. Memory bandwidth and computational capacity need to be exploited in ...
    • Performance impact of the grid middleware 

      Carrera Pérez, David; Guitart Fernández, Jordi; Beltran Querol, Vicenç; Torres Viñals, Jordi; Ayguadé Parra, Eduard (American Scientific Publishers, 2006-01)
      Part of book or chapter of book
      Open Access
      The Open Grid Services Architecture (OGSA) defines a new vision of the Grid based on the use of Web Services (Grid Services). The standard interfaces, behaviors and schemes that are consistent with the OGSA specification ...
    • Saiph, a domain specific language for computational fluid dynamics simulations 

      Macià, Sandra; Beltran Querol, Vicenç; Mira, Daniel; Mateo, Sergi (Barcelona Supercomputing Center, 2017-05-04)
      Open Access
      Nowadays, High-Performance Computing (HPC) is assuming an increasingly central role in scientific research while computer architectures are becoming more and more hetero-geneous and using different parallel programming ...
    • Saiph: towards a DSL for high-performance computational fluid dynamics 

      Macià, Sandra; Mateo, Sergi; Martínez-Ferrer, Pedro J.; Beltran Querol, Vicenç; Mira, Daniel; Ayguadé Parra, Eduard (Association for Computing Machinery (ACM), 2018)
      Conference report
      Restricted access - publisher's policy
      Nowadays high-performance computing is taking an increasingly central role in scientific research while computer architectures are becoming more heterogeneous and complex with different parallel programming models and ...
    • Scaling irregular array-type reductions in OmpSs 

      Ciesko, Jan; Mateo Bellido, Sergi; Teruel, Xavier; Beltran Querol, Vicenç; Martorell Bofill, Xavier; Badia Sala, Rosa Maria; Labarta Mancho, Jesús José (Barcelona Supercomputing Center, 2015-05-05)
      Conference report
      Open Access
      Array-type reductions represent a frequently occurring algorithmic pattern in many scientific applications. A special case occurs if array elements are accessed in a non-linear, often random manner, which makes their ...
    • Simulating complex systems with a low-detail model 

      Nou Castell, Ramon; Guitart Fernández, Jordi; Beltran Querol, Vicenç; Carrera Pérez, David; Montero Mercadé, Lídia; Torres Viñals, Jordi; Ayguadé Parra, Eduard (2005-09)
      Conference report
      Open Access
      In this paper we show how modeling and simulating a complex system such as a web-server can help to evaluate di erent metrics and proposals to improve the performance without necessity of using a real system. Many times ...
    • Speeding up distributed MapReduce applications using hardware accelerators 

      Becerra Fontal, Yolanda; Beltran Querol, Vicenç; Carrera Pérez, David; González Tallada, Marc; Torres Viñals, Jordi; Ayguadé Parra, Eduard (2009-09)
      Conference report
      Open Access
      In an attempt to increase the performance/cost ratio, large compute clusters are becoming heterogeneous at multiple levels: from asymmetric processors, to different system architectures, operating systems and networks. ...
    • Supporting automatic recovery in offloaded distributed programming models through MPI-3 techniques 

      Peña, Antonio J.; Beltran Querol, Vicenç; Clauss, Carsten; Moschny, Thomas (ACM Digital Library, 2017-06-15)
      Conference lecture
      Open Access
      In this paper we describe the design of fault tolerance capabilities for general-purpose offload semantics, based on the OmpSs programming model. Using ParaStation MPI, a production MPI-3.1 implementation, we explore the ...
    • Task-based programming with OmpSs and its application 

      Fernandez, Alejandro; Beltran Querol, Vicenç; Martorell Bofill, Xavier; Badia,, R.M.; Ayguadé Parra, Eduard; Labarta Mancho, Jesús José (Springer, 2014)
      Conference report
      Open Access
      OmpSs is a task-based programming model that aims to provide portability and flexibility for sequential codes while the performance is achieved by the dynamic exploitation of the parallelism at task level. OmpSs targets ...
    • Task-parallel reductions in OpenMP and OmpSs 

      Ciesko, Jan; Mateo, Sergi; Teruel, Xavier; Beltran Querol, Vicenç; Martorell Bofill, Xavier; Badia,, R.M.; Ayguadé Parra, Eduard; Labarta Mancho, Jesús José (Springer, 2014)
      Conference report
      Open Access
      The wide adoption of parallel processing hardware in mainstream computing as well as the raising interest for efficient parallel programming in the developer community increase the demand for parallel programming model ...
    • The OmpSs reductions model and how to deal with scatter-updates 

      Ciesko, Jan; Mateo Bellido, Sergi; Teruel, Xavier; Beltran Querol, Vicenç; Martorell Bofill, Xavier; Badia Sala, Rosa Maria; Labarta Mancho, Jesús José (Barcelona Supercomputing Center, 2015-05-05)
      Conference report
      Open Access
      Scatter-updates represent a reoccurring algorithmic pattern in many scientific applications. Their scalable execution on modern systems is difficult due to performance limitations introduced by their irregular memory access ...
    • Towards data-flow parallelization for adaptive mesh refinement applications 

      Sala Penadés, Kevin; Rico Carro, Alejandro; Beltran Querol, Vicenç (Institute of Electrical and Electronics Engineers (IEEE), 2020)
      Conference report
      Open Access
      Adaptive Mesh Refinement (AMR) is a prevalent method used by distributed-memory simulation applications to adapt the accuracy of their solutions depending on the turbulent conditions in each of their domain regions. These ...
    • Variable batched DGEMM 

      Valero-Lara, Pedro; Martinez-Perez, Ivan; Mateo, Sergio; Sirvent Pardell, Raül; Beltran Querol, Vicenç; Martorell Bofill, Xavier; Labarta Mancho, Jesús José (Institute of Electrical and Electronics Engineers (IEEE), 2018)
      Conference report
      Open Access
      Many scientific applications are in need to solve a high number of small-size independent problems. These individual problems do not provide enough parallelism and then, these must be computed as a batch. Today, vendors ...