I am experimenting with google compute engine (GCE) to run some scientific/engineering software. I have successfully tested the system on GCE using an 8 core, non-preemptible instance running over a long time period. I'm now testing with a 32 core preemptible instance but finding that the instance stops running after a relatively short time (certainly less than an hour). Although it's preemptible, I was under the impression from the docs that it was relatively unlikely to be stopped under typical circumstances.
I would like to know if there is some way to determine why the instance was stopped (I don't see any kind of log, at least in the web interface), get suggestions for causes of this, and suggestions for remedies or ways to prevent it.
In case it is relevant I'm in the trial period of GCE using free credit. By default you are only supposed to have a maximum of 24 cores, but I requested a quota increase to 32 cores so I could test my system on this instance type.
I am going to attempt a run with a non-preemptible instance to see if this makes any difference. I'll update this question with an edit later to report the results of this.