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Title: Clock Agreement Among Parallel Supercomputer Nodes

This dataset presents measurements that quantify the clock synchronization time-agreement characteristics among several high performance computers including the current world's most powerful machine for open science, the U.S. Department of Energy's Titan machine sited at Oak Ridge National Laboratory. These ultra-fast machines derive much of their computational capability from extreme node counts (over 18000 nodes in the case of the Titan machine). Time-agreement is commonly utilized by parallel programming applications and tools, distributed programming application and tools, and system software. Our time-agreement measurements detail the degree of time variance between nodes and how that variance changes over time. The dataset includes empirical measurements and the accompanying spreadsheets.
Authors:
;
Publication Date:
DOE Contract Number:
AC05-00OR22725
Product Type:
Dataset
Research Org(s):
ORNL-OLCF (Oak Ridge Leadership Computing Facility, Oak Ridge National Laboratory, Oak Ridge, TN)
Collaborations:
Oak Ridge National Laboratory (ORNL)
Sponsoring Org:
USDOE Office of Science (SC)
Subject:
97 MATHEMATICS AND COMPUTING; Clock Agreement; Clock Synchronization; Time Service; Supercomputing; Empirical Measurements
OSTI Identifier:
1130048
  1. The Oak Ridge Leadership Computing Facility (OLCF) was established at Oak Ridge National Laboratory in 2004 with the mission of accelerating scientific discovery and engineering progress by providing outstanding computing and data management resources to high-priority research and development projects. OLCF unveiled Titan in 2013, which is capable of 27 petaflops. Titan is one of the first hybrid architecture systems—a combination of graphics processing units (GPUs), and the more conventional central processing units (CPUs) that have served as number crunchers in computers for decades. The OLCF gives the world’s most advanced computational researchers an opportunity to tackle problems that wouldmore » be unthinkable on other systems. The DOI Portal can be found at https://doi.ccs.ornl.gov/. « less
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