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DOE OSTI · 1168674

Synchronizing compute node time bases in a parallel computer

Chen, Dong·Faraj, Daniel A·Gooding, Thomas M·Heidelberger, Philip
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Abstract

Synchronizing time bases in a parallel computer that includes compute nodes organized for data communications in a tree network, where one compute node is designated as a root, and, for each compute node: calculating data transmission latency from the root to the compute node; configuring a thread as a pulse waiter; initializing a wakeup unit; and performing a local barrier operation; upon each node completing the local barrier operation, entering, by all compute nodes, a global barrier operation; upon all nodes entering the global barrier operation, sending, to all the compute nodes, a pulse signal; and for each compute node upon receiving the pulse signal: waking, by the wakeup unit, the pulse waiter; setting a time base for the compute node equal to the data transmission latency between the root node and the compute node; and exiting the global barrier operation.

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97 MATHEMATICS AND COMPUTING

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BibTeXRIS

Chen, Dong, Faraj, Daniel A, Gooding, Thomas M, Heidelberger, Philip. 2015-01-27. Synchronizing compute node time bases in a parallel computer. https://www.osti.gov/biblio/1168674

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