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etmc / tmLQCD

tmLQCD is a freely available software suite providing a set of tools to be used in lattice QCD simulations. This is mainly a HMC implementation (including PHMC and RHMC) for Wilson, Wilson Clover and Wilson twisted mass fermions and inverter for different versions of the Dirac operator. The code is fully parallelised and ships with optimisations for various modern architectures, such as commodity PC clusters and the Blue Gene family.
http://www.itkp.uni-bonn.de/~urbach/software.html
GNU General Public License v3.0
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ddU in return_check comes out as NaN or silly large when running without SSE with GCC #466

Open kostrzewa opened 5 years ago

kostrzewa commented 5 years ago

1) running without explicit SSE is now faster when compiled with GCC than if explicit SSE stuff is enabled (strange, huh?) (GCC 7.4.0) 2) in return_check.data, ddU comes out as NaN or some insanely large number in the return check for reasons which are not clear to me. When compiled with SSE, this is not the case.

Everything else seems to work correctly. In particular, there don't seem to be any problems in the clover derivative or the clover term where _su3_minus_su3 is used as well.

I cannot identify where the problem originates, but it does not seem to affect anything else. Still worth investigating!

kostrzewa commented 5 years ago

I haven't tested other architectures, nor do I really have the time to do so...

kostrzewa commented 5 years ago

seems to be related to threading...