Now showing items 1-20 of 48

    • A fault-tolerant algorithm for distributed resource allocation 

      Pessolani, Pablo; Jara, Oscar; Gonnet, Silvio; Cortés, Toni; Tinetti, Fernando (2017-11-01)
      Article
      Open Access
      Resource allocation is a usual problem that must be faced during a distributed system design. Despite the large number of algorithms proposed in literature to solve this problem, most papers lack of detailed descriptions ...
    • A study on data deduplication in HPC storage systems 

      Meister, Dirk; Kaiser, Jürgen; Brinkmann, Andre; Cortés, Toni; Kuhn, Michael; Kunkel, Julian (Institute of Electrical and Electronics Engineers (IEEE), 2012)
      Conference report
      Restricted access - publisher's policy
      Deduplication is a storage saving technique that is highly successful in enterprise backup environments. On a file system, a single data block might be stored multiple times across different files, for example, multiple ...
    • AbacusFS integrated storage and computational platform 

      Nuhic, Isak; Šterk, Marjan; Cortés, Toni (Institute of Electrical and Electronics Engineers (IEEE), 2012)
      Conference report
      Open Access
      Today's applications, especially those in the scientific community, deal with an ever growing amount of data. Among the problems that arise from this explosion of data are how to organize the data so that the information ...
    • Ad hoc file systems for high-performance computing 

      Brinkmann, Andre; Mohror, Kathryn; Yu, Weikuan; Carns, Philip; Cortés, Toni; Klasky, Scott A.; Miranda Bueno, Alberto; Pfreundt, Franz-Josef; Ross, Robert B.; Vef, Marc-André (2020-01-17)
      Article
      Open Access
      Storage backends of parallel compute clusters are still based mostly on magnetic disks, while newer and faster storage technologies such as flash-based SSDs or non-volatile random access memory (NVRAM) are deployed within ...
    • Adaptive request scheduling for the I/O forwarding layer using reinforcement learning 

      Bez, Jean Luca; Zanon Boito, Francieli; Nou Castell, Ramon; Miranda Bueno, Alberto; Cortés, Toni; Navaux, Philippe O.A. (Elsevier, 2020-11)
      Article
      Restricted access - publisher's policy
      In this paper, we propose an approach to adapt the I/O forwarding layer of HPC systems to applications’ access patterns. I/O optimization techniques can improve performance for the access patterns they were designed to ...
    • An architecture model for a distributed virtualization system 

      Pessolani, Pablo; Tinetti, Fernando; Cortés, Toni; Gonnet, Silvio (International Academy, Research, and Industry Association (IARIA), 2018)
      Conference report
      Restricted access - publisher's policy
      This article presents an architecture model for a Distributed Virtualization System, which could expand a virtual execution environment from a single physical machine to several nodes of a cluster. With current virtualization ...
    • An empirical evaluation of how the network impacts the performance and energy efficiency in RAMCloud 

      Taleb, Yacine; Ibrahim, Shadi; Antoniu, Gabriel; Cortés, Toni (Institute of Electrical and Electronics Engineers (IEEE), 2017)
      Conference report
      Open Access
      In-memory storage systems emerged as a de-facto building block for today's large scale Web architectures and Big Data processing frameworks. Many research and engineering efforts have been dedicated to improve their ...
    • Analyzing long-term access locality to find ways to improve distributed storage systems 

      Miranda Bueno, Alberto; Cortés, Toni (2012)
      Conference report
      Open Access
      An efficient design for a distributed filesystem originates from a deep understanding of common access patterns and user behavior which is obtained through a deep analysis of traces and snapshots. In this paper we analyze ...
    • Automatic I/O scheduler selection through online workload analysis 

      Nou Castell, Ramon; Giralt, Jacobo; Cortés, Toni (2013)
      Conference report
      Open Access
      I/O performance is a bottleneck for many workloads. The I/O scheduler plays an important role in it. It is typically configured once by the administrator and there is no selection that suits the system at every time. Every ...
    • Better cloud storage usability through name space virtualization 

      Artiaga Amouroux, Ernest; Marti Fraiz, Jonathan; Cortés, Toni (Institute of Electrical and Electronics Engineers (IEEE), 2013)
      Conference report
      Restricted access - publisher's policy
      Cloud-based storage synchronization and backup services are widely available. Nevertheless, their usability is often rigid and coarse-grained: for example, most services synchronize specific whole directories, but are not ...
    • CAPre: Code-Analysis based Prefetching for Persistent object stores 

      Touma, Rizkallah; Queralt Calafat, Anna; Cortés, Toni (Elsevier, 2019-11-12)
      Article
      Open Access
      Data prefetching aims to improve access times to data storage systems by predicting data records that are likely to be accessed by subsequent requests and retrieving them into a memory cache before they are needed. In the ...
    • Characterizing performance and energy-efficiency of the RAMCloud storage system 

      Taleb, Yacine; Ibrahim, Shadi; Antoniu, Gabriel; Cortés, Toni (Institute of Electrical and Electronics Engineers (IEEE), 2017)
      Conference report
      Open Access
      Most large popular web applications, like Facebook and Twitter, have been relying on large amounts of in-memory storage to cache data and offer a low response time. As the main memory capacity of clusters and clouds ...
    • Cooperative caching and prefetching in parallel/distributed file systems 

      Cortés, Toni (Universitat Politècnica de Catalunya, 1997-12-12)
      Doctoral thesis
      Open Access
    • CRAID: Online RAID upgrades using dynamic hot data reorganization 

      Miranda Bueno, Alberto; Cortés, Toni (USENIX Association, 2014)
      Conference report
      Open Access
      Current algorithms used to upgrade RAID arrays typically require large amounts of data to be migrated, even those that move only the minimum amount of data required to keep a balanced data load. This paper presents CRAID, ...
    • Dataclay: A distributed data store for effective inter-player data sharing 

      Marti Fraiz, Jonathan; Queralt Calafat, Anna; Gasull Moreira, Daniel; Barceló Cuerda, Alex; Costa Prats, Juan José; Cortés, Toni (2017-09-01)
      Article
      Open Access
      In the Big Data era, both the academic community and industry agree that a crucial point to obtain the maximum benefits from the explosive data growth is integrating information from different sources, and also combining ...
    • Direct lookup and hash-based metadata placement for local file systems 

      Lensing, Paul Hermann; Cortés, Toni; Brinkmann, Andre (Association for Computing Machinery (ACM), 2013)
      Conference report
      Restricted access - publisher's policy
      New challenges to file systems' metadata performance are imposed by the continuously growing number of files existing in file systems. The total amount of metadata can become too big to be cached, potentially leading to ...
    • Distributing orthogonal redundancy on adaptive disk arrays 

      González, José Luis; Cortés, Toni (Springer, 2008)
      Conference report
      Restricted access - publisher's policy
      When upgrading storage systems, the key is migrating data from old storage subsystems to the new ones for achieving a data layout able to deliver high performance I/O, increased capacity and strong data availability while ...
    • DYON: Managing a new scheduling class to improve system performance in multicore systems 

      Nou Castell, Ramon; Giralt Celiméndiz, Jacobo; Cortés, Toni (Springer, 2013)
      Conference report
      Open Access
      Due to the increase in the number of available cores in current systems, plenty of system software starts to use some of these cores to perform tasks that will help optimize the application behaviour. Unfortunately, current ...
    • ECHOFS: a scheduler-guided temporary filesystem to leverage node-local NVMS 

      Miranda, Alberto; Nou Castell, Ramon; Cortés, Toni (Institute of Electrical and Electronics Engineers (IEEE), 2018)
      Conference report
      Open Access
      The growth in data-intensive scientific applications poses strong demands on the HPC storage subsystem, as data needs to be copied from compute nodes to I/O nodes and vice versa for jobs to run. The emerging trend of adding ...
    • Evaluating the effectiveness of REDCAP to recover the locality missed by today's Linux Systems 

      González Férez, Pilar; Piernas, Juan; Cortés, Toni (2008-10)
      Conference lecture
      Open Access
      In order to know how different conditions influence the behavior of the RAM Enhanced Disk Cache Project (REDCAP), we have analyzed the impact of the file system and the REDCAP cache size. The results show that, for workloads ...