Data and thread affinity in openmp programs
Christian Terboven, Dieter an Mey, Dirk Schmidl, Henry Jin, Thomas Reichstein · 2008
The slogan of last year's International Workshop on OpenMP was "A Practical Programming Model for the Multi-Core Era", although OpenMP still is fully hardware architecture agnostic. As a consequence the programmer is left alone with bad performance if threads and data happen to live apart. In this work we examine the programmer's possibilities to improve data and thread affinity in OpenMP programs for several toy applications and present how to apply the lessons learned on larger application codes. We filled a gap by implementing explicit data migration on Linux providing a next touch mechanism.