Public bug reported: More in-depth discussion can be found here:
http://lists.openstack.org/pipermail/openstack- dev/2015-February/056695.html Basically - there is a number of filters that need to be re-run even if we force a host. The reasons are two-fold. Placing some instances on some hosts is an obvious mistake and should be disallowed (instances with specific CPU pinning are an example), though this will be eventually rejected by the host. Second reason is that claims logic on compute hosts depends on limits being set by the filters, and if they are not some of the oversubscription as well as more complex placement logic will not work for the instance (see the following bug report as to how it impacts NUMA placement logic https://bugzilla.redhat.com/show_bug.cgi?id=1189906) Overall completely bypassing the filters is not ideal. ** Affects: nova Importance: Low Assignee: Sylvain Bauza (sylvain-bauza) Status: Confirmed ** Tags: scheduler -- You received this bug notification because you are a member of Yahoo! Engineering Team, which is subscribed to OpenStack Compute (nova). https://bugs.launchpad.net/bugs/1427772 Title: Instance that uses force-host still needs to run some filters Status in OpenStack Compute (Nova): Confirmed Bug description: More in-depth discussion can be found here: http://lists.openstack.org/pipermail/openstack- dev/2015-February/056695.html Basically - there is a number of filters that need to be re-run even if we force a host. The reasons are two-fold. Placing some instances on some hosts is an obvious mistake and should be disallowed (instances with specific CPU pinning are an example), though this will be eventually rejected by the host. Second reason is that claims logic on compute hosts depends on limits being set by the filters, and if they are not some of the oversubscription as well as more complex placement logic will not work for the instance (see the following bug report as to how it impacts NUMA placement logic https://bugzilla.redhat.com/show_bug.cgi?id=1189906) Overall completely bypassing the filters is not ideal. To manage notifications about this bug go to: https://bugs.launchpad.net/nova/+bug/1427772/+subscriptions -- Mailing list: https://launchpad.net/~yahoo-eng-team Post to : [email protected] Unsubscribe : https://launchpad.net/~yahoo-eng-team More help : https://help.launchpad.net/ListHelp
