High load on instance preventing live migration (Juno)
Hi,
I have run into situations where live migrations never seem to complete or error out.
Here is how I have been able to reproduce the problem.
Here is the instance I am migrating:
[root@osc1-mgmt-001 tmp]# nova show gb72-net-002-org-001
+--------------------------------------+---------------------------------------------------------------------+
| Property | Value |
+--------------------------------------+---------------------------------------------------------------------+
| OS-DCF:diskConfig | MANUAL |
| OS-EXT-AZ:availability_zone | nova |
| OS-EXT-SRV-ATTR:host | osc1-net-002.example.com |
| OS-EXT-SRV-ATTR:hypervisor_hostname | osc1-net-002.example.com |
| OS-EXT-SRV-ATTR:instance_name | gb72-net-002-org-001 |
| OS-EXT-STS:power_state | 1 |
| OS-EXT-STS:task_state | migrating |
| OS-EXT-STS:vm_state | active |
| OS-SRV-USG:launched_at | 2016-05-12T20:01:23.000000 |
| OS-SRV-USG:terminated_at | - |
| accessIPv4 | |
| accessIPv6 | |
| config_drive | |
| created | 2016-05-12T20:00:58Z |
| flavor | gb72_vm (668ca3b4-a7c0-4309-a11e-4fb5377e4180) |
| hostId | 44206a2390a038b0ede2a4375f1239b0cef917149bd5976fcada6781 |
| id | 3b176ee2-fcf3-41a6-b658-361ffd19639e |
| image | CentOS-7-x86_64-GenericCloud (588e035d-2e1e-4720-94c4-8b000bf9d2ef) |
| key_name | nk |
| metadata | {} |
| name | gb72-net-002-org-001 |
| os-extended-volumes:volumes_attached | [{"id": "16afe52c-31b0-4a3a-b718-aa1789df2852"}] |
| public-47 network | 10.29.105.13 |
| security_groups | default |
| status | MIGRATING |
| tenant_id | 9d011b7c8d104af1b887e229cee436d2 |
| updated | 2016-05-13T17:07:48Z |
| user_id | fa8b956c89304124967bb4bcea54124b |
+--------------------------------------+---------------------------------------------------------------------+
The flavor gb72_vm
is one I created and looks like this:
[root@osc1-mgmt-001 tmp]# nova flavor-show gb72_vm
+----------------------------+--------------------------------------+
| Property | Value |
+----------------------------+--------------------------------------+
| OS-FLV-DISABLED:disabled | False |
| OS-FLV-EXT-DATA:ephemeral | 0 |
| disk | 20 |
| extra_specs | {} |
| id | 668ca3b4-a7c0-4309-a11e-4fb5377e4180 |
| name | gb72_vm |
| os-flavor-access:is_public | True |
| ram | 72000 |
| rxtx_factor | 1.0 |
| swap | 16000 |
| vcpus | 8 |
+----------------------------+--------------------------------------+
After I launched the instance I installed stress
and I am running stress on the instance like so:
[centos@gb72-net-002-org-001 stress-1.0.4]$ stress -c 6 -m 4 --vm-bytes 512M
I am also running top
on the instance and this is what that looks like:
top - 17:17:02 up 21:15, 1 user, load average: 10.11, 10.08, 10.06
Tasks: 149 total, 12 running, 137 sleeping, 0 stopped, 0 zombie
%Cpu(s): 62.0 us, 38.0 sy, 0.0 ni, 0.0 id, 0.0 wa, 0.0 hi, 0.0 si, 0.0 st
KiB Mem : 72323392 total, 70503632 free, 1344768 used, 474988 buff/cache
KiB Swap: 16383996 total, 16383996 free, 0 used. 70740048 avail Mem
PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
10273 centos 20 0 7260 96 0 R 86.7 0.0 1008:21 stress
10276 centos 20 0 7260 96 0 R 84.7 0.0 1008:22 stress
10271 centos 20 0 7260 96 0 R 84.1 0.0 1008:00 stress
10275 centos 20 0 7260 96 0 R 82.1 0.0 1009:28 stress
10270 centos 20 0 531552 218716 176 R 80.7 0.3 1011:42 stress
10272 centos 20 0 531552 142940 176 R 80.4 0.2 1012:40 stress
10269 centos 20 0 7260 96 0 R 78.7 0.0 1008:38 stress
10274 centos 20 0 531552 333404 176 R 73.1 0.5 1012:32 stress
10267 centos 20 0 7260 96 0 R 70.4 0.0 1008:41 stress
10268 centos 20 0 531552 38452 176 R 65.8 0.1 1011:29 stress
1 root 20 0 191352 6652 3908 S 0.0 0.0 0:06.00 systemd
2 root 20 0 0 0 0 S 0.0 0.0 0:00.02 kthreadd
3 root 20 0 0 0 0 S 0.0 0.0 0:01.45 ksoftirqd/0
5 root ...