[ESPResSo-devel] [bug #44133] Temperature in LB_GPU is too high

[Axel Arnold]

Update of bug #44133 (project espressomd):

             Assigned to:                    None => jdegraaf               

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Follow-up Comment #2:

Regarding (4): Could you elaborate in what way global seed plus thread index
is improper seeding? Provided we use a reasonably uncorrelated RNG, that would
be correct and is actually a usual approach to many core seeding. Using for
example the RNG to initialize the seeds for the nodes in turn would be plain
wrong, because that introduces correlations.

If you see nearly identical progression of the kinetic energy, that rather
indicates that the RNG seed isn't used.

Regarding (5): That's likely the one you want to hunt down. The program might
initially start always the same because the initial memory contents is the
same, but with time due to MPI/PCI timing jitter you will get different memory
contents at places the code isn't supposed to read. And be advised that last
time we had such a reading of uninitialized memory, valgrind was unable to
detect it. printf debugging works though, but you need to be able to handle GB
size of logs.

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