gauss-mix randomly fails on CI

[vhotspur]

Randomly but quite often (I would say one in five builds, perhaps) gauss-mix benchmark fails when run as part of the CI.

It does not fail with some assertion/exception but rather stays in some endless loop (probably) as the job time-outs without any apparent reason (just gauss-mix is the last benchmark that was started).

From my experience this happens more often (maybe only?) in the standalone runs, i.e. when the main (fat) JAR is unpacked and we run single/gauss-mix.jar directly.

I was unable to reproduce the failure locally (even using the build artifact). At the moment it happily runs for several days on my machine without a glitch.

I do not expect we would solve this any time soon but it should be known at least.

[lbulej]

I also could not reproduce it locally, I saw it first in CI which has much less resources :-(