Comment 5 for bug 1750337

As I discussed with Ihar on IRC, it might be that host is just overloaded. There is 8 test workers, and each of them spawns neutron-server with 1 rpc_worker, 1 rpc_state_report_workers and 8 api_workers. So it's at least 80 workers spawned together.
I will try to limit number of api-workers in neutron-server to 2 and check if that will help.