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Mon, 11 Jun 2012

1.5M CPU hours in 2012

1.5M CPU hours runs on the Vienna Scientific Cluster by my 3D+3V hard expanding loops code. It is simulating the Chromo-Weibel instability of a non-Abelian plasma in an 1d expanding background to account for the expansion of a Quark-Gluon plasma fireball in a heavy ion collision. The code is parallellised using Open MPI and one single run roughly needs 0.5TB memory to hold all the needed 5-dimensional matrices and ~ 72h to complete. The resulting heavy operation is of course matrix multiplication of those physical and auxilliary fields.

I tried to use git-annex on the resulting physical fields data output of ~ 150Gb and 300k files. Currently I do prefer git itself for it's speed and it only doubles the amounted space. I'm thrilled to see that git annex is still considering this "semi-extreme" usecase of lots of data files as it would help collaborators to have partial checkouts for laptop usage and quick checks. As the git-annex kickstarter is a rocket, i'd add my wish to see the current symlink mess go: desymlink git-annex.

Now it is the time to properly analyse all this data and get the full 3d paper follow up on Instabilities of an anisotropically expanding non-Abelian plasma: 1D+3V discretized hard-loop simulations (previous paper) out maybe soon. (;

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