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—Roadrunner is a 1.38 Pflop/s-peak (double precision) hybrid-architecture supercomputer developed by LANL and IBM. It contains 12,240 IBM PowerXCell 8i processors and 12,240 AMD Opteron cores in 3,060 compute nodes. Roadrunner is the first supercomputer to run Linpack at a sustained speed in excess of 1 Pflop/s. In this paper we present a detailed(More)
In this work we present an initial performance evaluation of Intel's latest, second-generation quad-core processor, Nehalem, and provide a comparison to first-generation AMD and Intel quad-core processors Barcelona and Tigerton. Nehalem is the first In-tel processor to implement a NUMA architecture incorporating QuickPath Interconnect for interconnecting(More)
We describe the software architecture, technical features , and performance of TICK (Transparent Incre-mental Checkpointer at Kernel level), a system-level checkpointer implemented as a kernel thread, specifically designed to provide fault tolerance in Linux clusters. This implementation, based on the 2.6.11 Linux kernel, provides the essential(More)
Summary form only given. In the near future large-scale parallel computers will feature hundreds of thousands of processing nodes. In such systems, fault tolerance is critical as failures will occur very often. Checkpointing and rollback recovery has been extensively studied as an attempt to provide fault tolerance. However, current implementations do not(More)
Most standard cluster interconnect technologies are flexible with respect to network topology. This has spawned a substantial amount of research on topology-agnostic routing algorithms, which make no assumption about the network structure, thus providing the flexibility needed to route on irregular networks. Actually, such an irregularity should be often(More)
Networks of workstations (NOWs) are being considered as a cost-effective alternative to parallel computers. Most NOWs are arranged as a switch-based network and provide mechanisms for discovering the network topology. Hence, they provide support for both regular and irregular topologies, which makes routing and deadlock avoidance quite complicated. Current(More)
In order to take full advantage of multi-core processors careful attention must be given to the way in which each core interacts with main memory. In data-rich parallel applications multiple transfers between the main memory and local memory (cache or other) of each core will be required. It will be increasingly important to overlap these data transfers(More)
Interference of nearby jobs has been recently identified as the dominant reason for the high performance variability of parallel applications running on High Performance Computing (HPC) systems. Typically, HPC systems are dynamic with multiple jobs coming and leaving in an unpredictable fashion, sharing simultaneously the system interconnection network. In(More)
Checkpoint/restart is a general idea for which particular implementations enable various functionalities in computer systems, including process migration, gang scheduling, hibernation, and fault tolerance. For fault tolerance, in current practice, implementations can be at user-level or system-level. User-level implementations are relatively easy to(More)