Brian Kocoloski

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Performance isolation is emerging as a requirement for High Performance Computing (HPC) applications, particularly as HPC architectures turn to in situ data processing and application composition techniques to increase system throughput. These approaches require the co-location of disparate workloads on the same compute node, each with different resource(More)
Modified variants of Linux are likely to be the underlying operating systems for future exascale platforms. Despite the many advantages of this approach, a subset of applications exist in which a lightweight kernel (LWK) based OS is needed and/or preferred. We contend that virtualization is capable of supporting LWKs as virtual machines (VMs) running at(More)
With the growth of Infrastructure as a Service (IaaS) cloud providers, many have begun to seriously consider cloud services as a substrate for HPC applications. While the cloud promises many benefits for the HPC community, it currently does not come without drawbacks for application performance. These performance issues are generally the result of resource(More)
Current trends in exascale systems research indicate that heterogeneity will abound in both the hardware and software layers on future HPC systems. It is our position that exascale environments are likely to be constructed from independent partitions of hardware and system software called enclaves, with multiple enclaves co-located on the same physical(More)
Linux-based operating systems and runtimes (OS/Rs) have emerged as the environments of choice for the majority of HPC systems. While Linux-based OS/Rs have advantages such as extensive feature sets and developer familiarity, these features come at the cost of additional system overhead. In contrast to Linux, there is a substantial history of work in the HPC(More)
Current HPC system software lacks support for emerging application deployment scenarios that combine one or more simulations with in situ analytics, sometimes called multi-component or multi-enclave applications. This paper presents an initial design study, implementation, and evaluation of mechanisms supporting composite multi-enclave applications in the(More)
Linux-based operating systems and runtimes (OS/Rs) have emerged as the environments of choice for the majority of modern HPC systems. While Linux-based OS/Rs have advantages such as extensive feature sets as well as developer familiarity, these features come at the cost of additional overhead throughout the system. In contrast to Linux, there is a(More)
Performance variation is a significant problem for large scale HPC systems and will increase on future exascale systems. In this work, we show that performance variation impacts the performance and energy efficiency of contemporary large-scale computing systems in highly temporally inconsistent ways. We thus present a case for criticality models, a learning(More)
As supercomputers move to exascale, the number of cores per node continues to increase, but the I/O bandwidth between nodes is increasing more slowly. This leads to computational power outstripping I/O bandwidth. This growth, in turn, encourages moving as much of an HPC workflow as possible onto the node in order to minimize data movement. One particular(More)
The cost of inter-node I/O and data movement is becoming increasingly prohibitive for large scale High Performance Computing (HPC) applications. This trend is leading to the emergence of composed in situ applications that co-locate multiple components on the same node. However, these components may contend for underlying memory system resources. In this(More)