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Over the last twenty years, the open source community has provided more and more software on which the world's High Performance Computing (HPC) systems depend for performance and productivity. The community has invested millions of dollars and years of effort to build key components. But although the investments in these separate software elements have been(More)
Nondeterministic nature of parallel programs is the major difficulty in debugging. Order-replay, a technique to solve this problem, is widely used because of its small overhead. It has, however, several serious drawbacks: all processes of the parallel program have to participate in replay even when some of them are clearly not involved with the bug; and the(More)
In order to reduce the overhead of synchronizing operations of shared memory multiprocessors, this paper proposes a mechanism, named specMEM, to execute memory accesses following a synchronizing operation speculatively before the completion of the synchronization is conrmed. A unique feature of our mechanism is that the detection of speculation failure and(More)
In recent years, the use of cache memory has been desired in hard real-time systems in order to reduce the memory access time. To enable it, accurate analysis of the worst-case execution time considering cache flushes is necessary since the cache may be flushed by preempting tasks in a mul-titask environment. This paper proposes a method to find the(More)
In our research project " Mega-Scale Computing Based on Low-Power Technology and Workload Modeling " , we claim that a million-scale parallel system could be built with densely mounted low-power commodity processors. " MegaProto " is a proof-of-concept low-power and high-performance cluster build only with commodity components to implement this claim. A(More)
ABCG2, also known as BCRP, is a high-capacity urate exporter, the dysfunction of which raises gout/hyperuricemia risk. Generally, hyperuricemia has been classified into urate 'overproduction type' and/or 'underexcretion type' based solely on renal urate excretion, without considering an extra-renal pathway. Here we show that decreased extra-renal urate(More)