-2 to 10 minute downtimes. +1 to doing the evolution gracefully. There is a spec for doing that from the H summit; someone just needs to implement it.
-Rob On 25 October 2013 09:30, Michael Still <mi...@stillhq.com> wrote: > Hi. > > Because I am a grumpy old man I have just -2'ed > https://review.openstack.org/#/c/39685/ and I wanted to explain my > rationale. Mostly I am hoping for a consensus to form -- if I am wrong > then I'll happy remove my vote from this patch. > > This patch does the reasonably sensible thing of converting two > columns from being text to varchar, which reduces their expense to the > database. Given the data stored is already of limited length, it > doesn't impact our functionality at all either. > > However, when I run it with medium sized (30 million instances) > databases, the change does cause a 10 minute downtime. I don't > personally think the change is worth such a large outage, but perhaps > everyone else disagrees. > > Discuss. > > Thanks, > Michael > > PS: I could see a more complicated approach where we did these changes > "in flight" by adding columns, using a periodic task to copy data to > the new columns, and then dropping the old. That's a lot more > complicated to implement though. > > -- > Rackspace Australia > > _______________________________________________ > OpenStack-dev mailing list > OpenStack-dev@lists.openstack.org > http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev -- Robert Collins <rbtcoll...@hp.com> Distinguished Technologist HP Converged Cloud _______________________________________________ OpenStack-dev mailing list OpenStack-dev@lists.openstack.org http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev
