LHC@home

most are waiting for a 3rd host to re-run WU and validate or not.

for 70891665, no one could agree so it's marked as can't validate as the maxiumium number of tries is 5. In this case it's probally a bad WU as the probabilty of 4 different computers being bad is very low.

Eric could comment on how a WU could be bad from a fundemental perspective

We have seen some corner cases were simulations do behave weirdly and inconsistently. In fact, one of the test jobs Eric made once is on of those that with certain compiler configurations do produce different results in different run environments. I suspect these corner cases are simulations where multiple particles are lost, which is the case for Eric's test, and I have identified one issue that could potentially be the cause of these inconsistencies. Essentially, the particle lost flag may be read from an index outside the array where it's stored.

Out-of-bounds indices can also be caused by the input file for the WU having invalid settings that are not caught by the input file parser. We've identified and fixed a few such cases in the very old parts of the code, but there may be more. Our test suite is not good at catching these as the tests tend to have valid input files. These bugs are generally discovered by our users.

---

SixTrack 5 Core Developer. github.com/SixTrack/SixTrack