Inefficient use of db calls to get instance rules in virt/firewall.py

[Hans Lindgren]

When getting instance rules in virt/firewall.py a for loop is used to query the db for rules belonging to each individual security group in a list of security groups that itself comes from a separate query. See:

https://github.com/openstack/nova/blob/47e5199f67949f3cbd73114f4f45591cbc01bdd5/nova/virt/firewall.py#L349

This can be made much more efficient by querying all rules in a single db query joined by instance.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/259810

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/259810
Committed: https://git.openstack.org/cgit/openstack/nova/commit/?id=82636d678883788c3781164e3453b58bfa0661cf
Submitter: Jenkins
Branch: master

commit 82636d678883788c3781164e3453b58bfa0661cf
Author: Hans Lindgren <email address hidden>
Date: Fri Dec 11 11:19:07 2015 +0100

    Reduce the number of db/rpc calls to get instance rules

    When getting instance rules in virt/firewall.py a for loop is used to
    issue db queries for rules belonging to each individual security group
    in a list of security groups that itself is fetched using a separate
    query.

    This can be made much more efficient by querying all rules in a single
    db query joined by instance.

    Change-Id: I325f9c71fecde8297842fd608ac3cfd51ea9db71
    Closes-Bug: #1528041

[Thierry Carrez (ttx)]

This issue was fixed in the openstack/nova 13.0.0.0b2 development milestone.