Now showing items 1-20 of 23

    • A scalable synthetic traffic model of Graph500 for computer networks analysis 

      Fuentes Sáez, Pablo; Benito, Mariano; Vallejo, Enrique; Bosque Orero, José Luis; Beivide Palacio, Ramon; Anghel, Andreea; Rodríguez Herrera, Germán; Gusat, Mitch; Minkenberg, Cyriel; Valero Cortés, Mateo (2017-12-25)
      Article
      Open Access
      The Graph500 benchmark attempts to steer the design of High-Performance Computing systems to maximize the performance under memory-constricted application workloads. A realistic simulation of such benchmarks for architectural ...
    • Architectural support for task dependence management with flexible software scheduling 

      Castillo, Emilio; Álvarez Martí, Lluc; Moreto Planas, Miquel; Casas, Marc; Vallejo, Enrique; Bosque, Jose L.; Beivide Palacio, Ramon; Valero Cortés, Mateo (Institute of Electrical and Electronics Engineers (IEEE), 2018)
      Conference report
      Open Access
      The growing complexity of multi-core architectures has motivated a wide range of software mechanisms to improve the orchestration of parallel executions. Task parallelism has become a very attractive approach thanks to its ...
    • CATA: Criticality aware task acceleration for multicore processors 

      Castillo, Emilio; Moreto Planas, Miquel; Casas, Marc; Álvarez Martí, Lluc; Vallejo, Enrique; Chronaki, Kallia; Badia Sala, Rosa Maria; Bosque Orero, José Luis; Beivide Palacio, Julio Ramón; Ayguadé Parra, Eduard; Labarta Mancho, Jesús José; Valero Cortés, Mateo (Institute of Electrical and Electronics Engineers (IEEE), 2016)
      Conference report
      Open Access
      Managing criticality in task-based programming models opens a wide range of performance and power optimization opportunities in future manycore systems. Criticality aware task schedulers can benefit from these opportunities ...
    • Contention-based nonminimal adaptive routing in high-radix networks 

      Fuentes Sáez, Pablo; Vallejo, Enrique; García, Marina; Beivide Palacio, Julio Ramón; Rodríguez, Germán; Minkenberg, Cyriel; Valero Cortés, Mateo (Institute of Electrical and Electronics Engineers (IEEE), 2015)
      Conference report
      Open Access
      Adaptive routing is an efficient congestion avoidance mechanism for modern Datacenter and HPC networks. Congestion detection traditionally relies on the occupancy of the router queues. However, this approach can hinder ...
    • Efficient bypass in mesh and torus NoCs 

      Pérez, Iván; Vallejo, Enrique; Beivide, Ramón (Elsevier, 2020)
      Article
      Open Access
      Minimizing latency and power are key goals in the design of NoC routers. Different proposals combine lookahead routing and router bypass to skip the arbitration and buffering, reducing router delay. However, the conditions ...
    • Efficient routing mechanisms for Dragonfly networks 

      García, Marina; Vallejo, Enrique; Beivide Palacio, Julio Ramón; Odriozola, Miguel; Valero Cortés, Mateo (Institute of Electrical and Electronics Engineers (IEEE), 2013)
      Conference lecture
      Open Access
      High-radix hierarchical networks are cost-effective topologies for large scale computers. In such networks, routers are organized in super nodes, with local and global interconnections. These networks, known as Dragonflies, ...
    • FlexVC: Flexible virtual channel management in low-diameter networks 

      Fuentes, Pablo; Vallejo, Enrique; Beivide Palacio, Ramon; Minkenberg, Cyriel; Valero Cortés, Mateo (Institute of Electrical and Electronics Engineers (IEEE), 2017)
      Conference report
      Open Access
      Deadlock avoidance mechanisms for lossless lowdistance networks typically increase the order of virtual channel (VC) index with each hop. This restricts the number of buffer resources depending on the routing mechanism and ...
    • Global misrouting policies in two-level hierarchical networks 

      Garcia, Marina; Vallejo, Enrique; Beivide Palacio, Julio Ramón; Odriozola, Miguel; Camarero Coterillo, Cristobal; Valero Cortés, Mateo; Labarta Mancho, Jesús José; Rodríguez, Germán (2013)
      Conference report
      Restricted access - publisher's policy
      Dragonfly networks are composed of interconnected groups of routers. Adaptive routing allows packets to be forwarded minimally or non-minimally adapting to the traffic conditions in the network. While minimal routing sends ...
    • Hybrid transactional memory to accelerate safe lock-based transactions 

      Vallejo, Enrique; Harris, Tim; Cristal Kestelman, Adrián; Unsal, Osman Sabri; Valero Cortés, Mateo (Association for Computing Machinery (ACM), 2008)
      Conference report
      Open Access
      To reduce the overhead of Software Transactional Memory (STM) there are many recent proposals to build hybrid systems that use architectural support either to accelerate parts of a particular STM algorithm (Ha-TM), or ...
    • Hybrid transactional memory with pessimistic concurrency control 

      Vallejo, Enrique; Sanyal, Sutirtha; Harris, Tim; Vallejo, Fernando; Beivide, Ramón; Unsal, Osman Sabri; Cristal Kestelman, Adrián; Valero Cortés, Mateo (2011-06)
      Article
      Restricted access - publisher's policy
      Transactional Memory (TM) intends to simplify the design and implementation of the shared-memory data structures used in parallel software. Many Software TM systems are based on writer-locks to protect the data being ...
    • Implementing Kilo-Instruction multiprocessors 

      Vallejo, Enrique; Galluzzi, Marco; Cristal Kestelman, Adrián; Vallejo, Fernando; Beivide Palacio, Ramon; Stenström, Per; Smith, James E.; Valero Cortés, Mateo (Institute of Electrical and Electronics Engineers (IEEE), 2004)
      Conference report
      Open Access
      Multiprocessors are coming into wide-spread use in many application areas, yet there are a number of challenges to achieving a good tradeoff between complexity and performance. For example, while implementing memory coherence ...
    • Implementing kilo-instruction multiprocessors 

      Vallejo, Enrique; Galluzzi, Marco; Cristal Kestelman, Adrián; Vallejo, Fernando; Beivide Palacio, Ramon; Stenström, Per; Smith, James E.; Valero Cortés, Mateo (2005)
      Research report
      Open Access
      Multiprocessors are coming into wide-spread use in many application areas, yet there are a number of challenges to achieving a good tradeoff between complexity and performance. For example, while implementing memory coherence ...
    • Implicit transactional memory in chip multiprocessors 

      Galluzzi, Marco; Vallejo, Enrique; Cristal Kestelman, Adrián; Vallejo, Fernando; Beivide Palacio, Ramon; Stenström, Per; Smith, James E.; Valero Cortés, Mateo (2007-06)
      Research report
      Open Access
      Chip Multiprocessors (CMPs) are an efficient way of designing and use the huge amount of transistors on a chip. Different cores on a chip can compose a shared memory system with a very low-latency interconnect at a very ...
    • Implicit transactional memory in kilo-instruction multiprocessors 

      Galluzzi, Marco; Vallejo, Enrique; Cristal Kestelman, Adrián; Vallejo, Fernando; Beivide Palacio, Julio Ramon; Stenström, Per; Smith, James E.; Valero Cortés, Mateo (2007-06)
      Research report
      Open Access
      Although they have been the main server technology for many years, multiprocessors are undergoing a renaissance due to multi-core chips and the attractive scalability properties of combining a number of such multi-core ...
    • Network unfairness in dragonfly topologies 

      Fuentes, Pablo; Vallejo, Enrique; Camarero, Cristóbal; Beivide Palacio, Ramon; Valero Cortés, Mateo (2016-12)
      Article
      Open Access
      Dragonfly networks arrange network routers in a two-level hierarchy, providing a competitive cost-performance solution for large systems. Non-minimal adaptive routing (adaptive misrouting) is employed to fully exploit the ...
    • OFAR-CM: Efficient Dragonfly networks with simple congestion management 

      García, Marina; Vallejo, Enrique; Beivide Palacio, Ramon; Valero Cortés, Mateo; Rodríguez, Germán (Institute of Electrical and Electronics Engineers (IEEE), 2013)
      Conference report
      Open Access
      Dragonfly networks are appealing topologies for large-scale Data center and HPC networks, that provide high throughput with low diameter and moderate cost. However, they are prone to congestion under certain frequent traffic ...
    • On-the-fly adaptive routing for dragonfly interconnection networks 

      García, Marina; Vallejo, Enrique; Beivide Palacio, Julio Ramón; Camarero Coterillo, Cristobal; Valero Cortés, Mateo; Rodríguez Herrera, Germán; Minkenberg, Cyriel (2015-03-01)
      Article
      Open Access
      Adaptive deadlock-free routing mechanisms are required to handle variable traffic patterns in dragonfly networks. However, distance-based deadlock avoidance mechanisms typically employed in Dragonflies increase the router ...
    • Solving multiprocessor drawbacks with kilo-instruction processors 

      Vallejo, Enrique; Galluzzi, Marco; Cristal Kestelman, Adrián; Vallejo, Fernando; Beivide Palacio, Ramon; Stenström, Per; Smith, James E.; Valero Cortés, Mateo (2005)
      Research report
      Open Access
      Nowadays, a good multiprocessor system design has to deal with many drawbacks in order to achieve a good tradeoff between complexity and performance. For example, while solving problems like coherence and consistency is ...
    • Task mapping in rectangular twisted tori 

      Camarero Coterillo, Cristobal; Vallejo, Enrique; Martínez Fernández, Maria del Carmen; Moreto Planas, Miquel; Beivide Palacio, Julio Ramón (Association for Computing Machinery (ACM), 2013)
      Conference report
      Open Access
      Twisted torus topologies have been proposed as an alternative to toroidal rectangular networks, improving distance parameters and providing network symmetry. However, twisting is apparently less amenable to task mapping ...
    • The Mont-Blanc prototype: an alternative approach for high-performance computing systems 

      Rajovic, Nikola; Ramírez Bellido, Alejandro; Rico, Alejandro; Mantovani, Filippo; Ruiz, Daniel; Villarubi, Oriol; Gómez, Constantino; Backes, Luna; Nieto, Diego; Servat, Harald; Martorell Bofill, Xavier; Labarta Mancho, Jesús José; Ayguadé Parra, Eduard; Valero Cortés, Mateo; Adeniyi-Jones, Chris; Derradji, Said; Gloaguen, Hervé; Lanucara, Piero; Sanna, Nico; Mehaut, Jean-François; Pouget, Kevin; Videau, Brice; Boyer, Eric; Allalen, Momme; Auweter, Axel; Brayford, David; Tafani, Daniele; Brömmel, Dirk; Halver, René; Meinke, Jan H.; Beivide Palacio, Ramon; Benito, Mariano; Vallejo, Enrique (2016)
      Research report
      Open Access
      High-performance computing (HPC) is recognized as one of the pillars for further advance of science, industry, medicine, and education. Current HPC systems are being developed to overcome emerging challenges in order to ...