Re: [Engine-devel] [engine-devel] instance type as top-level entity

----- Original Message ----- > From: "Tomas Jelinek" <tjelinek(a)redhat.com&gt; > To: "engine-devel" <engine-devel(a)ovirt.org&gt; > Cc: "Omer Frenkel" <ofrenkel(a)redhat.com&gt; > Sent: Wednesday, December 4, 2013 2:14:06 PM > Subject: [engine-devel] instance type as top-level entity > > Hey all, > > I have started to work on the instance types[1] again and hit an issue. Since > the instance types are supposed to be top-level entities > (e.g. without the connection to DC/Cluster) but they are modeled as templates > it is not possible to store them to DB since the DB constraints violation on > vm_static table > (e.g. the vds_group_id has to be unique and point to an existing vds_group). > > So, I see 4 options: > > 1: drop the constraints on the vm_static.vds_group_id (the > vds_groups_vm_static constraint) > (most simple approach but would open the door to some issues which are now > guard on the DB level) > > 2: do the same magic [well, hacks :) ] as with the "blank" template which is > in the same situation > (not exactly a nice solution to have the instance types wired to one > specific cluster just to satisfy the constraint but return them all the > time) > > 3: do not store this data in vm_static but create some new table called e.g. > instance_type which would contain all of the fields from vm_static which are > needed by it > (actually the best approach AFAIK but to do it correctly it would require > some more refactoring to do some hierarchy of tables and not copy the > fields from table to table) > > 4: make the instance types not top-level (e.g. bound to specific DC/Cluster) > (would bring some issues for example with the default instance types which > should be present for all the DC/Clusters) > > Thoughts? > > Thank you, > Tomas > > [1]: http://www.ovirt.org/Features/Instance_Types > according to the wiki (and discussions we had) instance type is bounded to a cluster (even if only as a changeable default) so i dont think there is an issue..