The ephemeral disk and the swap disk locally in the nova-compute node when image_type=rbd

Bug #1420274 reported by Yogev Rabl
This bug affects 7 people
Affects Status Importance Assigned to Milestone
OpenStack Compute (nova)

Bug Description

Description of problem:
The Nova saves templates of the ephemeral and swap disks locally in the compute nodes, in /var/lib/nova/instances/_base directory

Version-Release number of selected component (if applicable):

How reproducible:

Steps to Reproduce:
1. Set Nova to work with Ceph as the back end of the compute nodes
2. Create a flavor that has ephemeral and swap disks
3. Launch an instance

Actual results:
Templates of the ephemeral and swap disks are been saved in the /var/lib/nova/instances/_base directory

Expected results:
These disks should be saved in the Ceph storage

Revision history for this message
Davanum Srinivas (DIMS) (dims-v) wrote :

How/what did you do in #1? example did you set images_type to 'rbd' in nova.conf?

Changed in nova:
status: New → Incomplete
Revision history for this message
Yogev Rabl (yrabl) wrote :

I have set the images_type to rbd, according to the manual in the formal Ceph documentation:

Changed in nova:
status: Incomplete → New
Revision history for this message
Sean Dague (sdague) wrote :

Marking as low as it is one storage back end. Operators were talking about this issue at the Philly midcycle, and I think this is mostly a ceph specific optimization that is needed here.

Changed in nova:
status: New → Confirmed
importance: Undecided → Low
tags: added: ceph
Revision history for this message
Michael Still (mikal) wrote :

I agree with Sean -- the image cache logic has no knowledge of the storage backends as best as I recall, it just makes things in _base and then moves them to whatever instance storage is configured. It would be interesting to get a feel for if operators thought this is a "big deal", or just a minor annoyance.

Revision history for this message
Eric Kolb (ekolb) wrote :

Yes, this annoying from an operators perspective. From what we experience the ephemeral disk gets created in /var/lib/nova/instances/_base/ first and then a "rbd import" is performed which can take significant time given large ephemeral disk definitions.

Changed in nova:
assignee: nobody → lyanchih (lyanchih)
Changed in nova:
assignee: Chung Chih, Hung (lyanchih) → nobody
Revision history for this message
Sean Dague (sdague) wrote :

Automatically discovered version juno in description. If this is incorrect, please update the description to include 'nova version: ...'

tags: added: openstack-version.juno
To post a comment you must log in.
This report contains Public information  
Everyone can see this information.

Other bug subscribers

Remote bug watches

Bug watches keep track of this bug in other bug trackers.