serveral neutron server process CPU punching height

[susan Li]

The bug will happen when 2000 routers are created by rally script.

rally script:
"NeutronNetworks.create_N_routers_M_network_M_subnet": [
        {
            "args": {
                "num_of_routers":1,
                "num_of_networks":1,
                "network_create_args": {},
                "subnet_create_args": {},
                "subnet_cidr_start": "2.1.3.0/24",
                "subnets_per_network": 1,
                "router_create_args": {
                   "external_gateway_info": {
                    "network_id":"65a81c28-6ea3-47be-9e4d-ca34fc0b0844"
                    }
                }
            },
            "runner": {
                "type": "constant",
                "times": 1,
                "concurrency": 1
            },
            "context": {
                "users": {
                    "tenants": 1,
                    "users_per_tenant": 1
                },
                "quotas": {
                    "neutron": {
                        "network": -1,
                        "subnet": -1,
                        "router": -1
                    }
                }
            }
        }
    ]
environment：openstack K
             api-workers = 24

phenomenon:
PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
28582 neutron 20 0 1972384 1.513g 2112 R 100.0 2.4 690:03.53 neutron-server
28587 neutron 20 0 2042504 1.582g 2108 R 100.0 2.5 753:38.91 neutron-server
28579 neutron 20 0 2405900 1.919g 2108 R 100.0 3.1 714:32.32 neutron-server
28581 neutron 20 0 2833136 2.326g 2108 R 100.0 3.7 723:43.28 neutron-server
28586 neutron 20 0 1969648 1.509g 2108 R 100.0 2.4 679:06.97 neutron-server
28588 neutron 20 0 2097372 1.626g 2108 R 100.0 2.6 735:03.23 neutron-server
28589 neutron 20 0 2054628 1.593g 2108 R 100.0 2.5 711:27.87 neutron-server
31289 neutron 20 0 346980 51872 5300 S 9.9 0.1 295:11.30 neutron-zenic-a
 1842 root 20 0 911552 10188 1700 S 8.9 0.0 3249:10 tecs-tc-main

[Launchpad Janitor (janitor)]

[Expired for neutron because there has been no activity for 60 days.]