overcloud-prep-images.sh does not finish

[Matthias Runge]

I'm running devmode: bash devmode.sh --no-gate --ovb -d -w /var/tmp/tripleo_local

Last commands in overcloud-prep-images.sh are:
## * Register nodes with Ironic.
## ::

openstack overcloud node import instackenv.json

## * Introspect hardware attributes of nodes.
## ::

        openstack overcloud node introspect --all-manageable
        openstack overcloud node provide --all-manageable

However, the last command does not timeout, or finish.

2018-01-10 11:02:29 | + openstack overcloud node import instackenv.json
2018-01-10 11:02:32 | Waiting for messages on queue 'tripleo' with no timeout.
2018-01-10 11:02:43 | Started Mistral Workflow tripleo.baremetal.v1.register_or_update. Execution ID: c48a7e58-3e35-4e49-9e82-712ad30a387c
2018-01-10 11:02:43 |
2018-01-10 11:02:43 |
2018-01-10 11:02:43 | Nodes set to managed.
2018-01-10 11:02:43 | Successfully registered node UUID a1c3a5e2-88d3-4437-be14-7a27eada1579
2018-01-10 11:02:43 | Successfully registered node UUID 41a0066e-7596-4014-b35e-a80035704361
2018-01-10 11:02:43 | + openstack overcloud node introspect --all-manageable
2018-01-10 11:02:46 | Waiting for messages on queue 'tripleo' with no timeout.
2018-01-10 11:27:09 | Waiting for introspection to finish...
2018-01-10 11:27:09 | Started Mistral Workflow tripleo.baremetal.v1.introspect_manageable_nodes. Execution ID: c6c83938-02db-4efe-9718-06b901915234
2018-01-10 11:27:09 | Introspection of node a1c3a5e2-88d3-4437-be14-7a27eada1579 timed out.
2018-01-10 11:27:09 | Introspection of node 41a0066e-7596-4014-b35e-a80035704361 timed out.
2018-01-10 11:27:09 | Retrying 2 nodes that failed introspection. Attempt 2 of 3
2018-01-10 11:27:09 | Introspection of node a1c3a5e2-88d3-4437-be14-7a27eada1579 completed. Status:SUCCESS. Errors:None
2018-01-10 11:27:09 | Introspection of node 41a0066e-7596-4014-b35e-a80035704361 completed. Status:SUCCESS. Errors:None
2018-01-10 11:27:09 | Successfully introspected nodes.
2018-01-10 11:27:09 | Nodes introspected successfully.
2018-01-10 11:27:09 | Introspection completed.
2018-01-10 11:27:09 | + openstack overcloud node provide --all-manageable
2018-01-10 11:27:12 | Waiting for messages on queue 'tripleo' with no timeout.

[Matthias Runge (mrunge)]

turns out, the vms ran out of memory.