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We present MRNet, a software-based multicast/reduction network for building scalable performance and system administration tools. MRNet supports multiple simultaneous, asynchronous collective communication operations. MRNet is flexible, allowing tool builders to tailor its process network topology to suit their tool's requirements and the underlying(More)
As high-end computing machines continue to grow in size, issues such as fault tolerance and reliability limit application scalability. Current techniques to ensure progress across faults, like checkpoint-restart, are increasingly problematic at these scales due to excessive overheads predicted to more than double an application's time to solution.(More)
We present the Stack Trace Analysis Tool (STAT) to aid in debugging extreme-scale applications. STAT can reduce problem exploration spaces from thousands of processes to a few by sampling stack traces to form process equivalence classes, groups of processes exhibiting similar behavior. We can then use full-featured debuggers on representatives from these(More)
SUMMARY The NetSolve Grid Computing System was first developed in the mid 1990s to provide users with seamless access to remote computational hardware and software resources. Since then, the system has benefitted from many enhancements like security services, data management faculties and distributed storage infrastructures. This article is meant to provide(More)
Current fault tolerance protocols are not sufficiently scalable for the exascale era. The most-widely used method, coordinated checkpointing, places enormous demands on the I/O subsystem and imposes frequent synchronizations. Uncoordinated protocols use message logging which introduces message rate limitations or undesired memory and storage requirements to(More)
SUMMARY Performance monitoring of HPC applications offers opportunities for adaptive optimization based on dynamic performance behavior, unavailable in purely post-mortem performance views. However, a parallel performance monitoring system must have low overhead and high efficiency to make these opportunities tangible. We describe a scalable parallel(More)
Large-scale server deployments in the commercial internet space have been using group based protocols such as peer-to-peer and gossip to allow coordination of services and data across global distributed data centers. Here we look at applying these methods, which are themselves derived from early work in distributed systems, to large-scale, tightly-coupled(More)
Petascale systems will present several new challenges to performance and correctness tools. Such machines may contain millions of cores, requiring that tools use scalable data structures and analysis algorithms to collect and to process application data. In addition, at such scales, each tool itself will become a large parallel application – already,(More)