3.5. Red Hat OpenStack Platform 10 Maintenance Release 16 January 2019

This update introduces vrouter multi-queue support required by a Juniper plug-in. 
One of Juniper's plug-ins relies on nova to create interfaces with the correct mode - multi-queue or single-queue.
vrouter VIFs (OpenContrail) now support multi-queue mode, which allows network performance to scale across multiple vCPUs. 
To use this feature, create an instance with more than one vCPU from an image that has the `hw_vif_multiqueue_enabled` property set to `true`.

This update adds maintenance release version information to the rhosp-release file.
For instance: 
....
$ cat ./etc/rhosp-release
Red Hat OpenStack Platform release 10.0.10 (Newton)
....

This update introduces a new config option, cpu_pinning_migration_quick_fail. 

The option only applies to instances with pinned CPUs. It controls the failing of live migrations in the scheduler if the required CPUs aren't available on the destination host.

When an instance with CPU pinning is live migrated, the upstream behavior is to keep the CPU mapping on the destination identical to the source. This can result in multiple instances pinned to the same host CPUs. OSP contains a downstream workaround (absent from upstream OpenStack) that prevents live migration if the required CPUs aren't available on the destination host.

The workaround's implementation places the same destination CPU availability restrictions on all other operations that involve scheduling an instance on a new host. These are cold migration, evacuation, resize and unshelve. For these operations, the instance CPU pinning is recalculated to fit the new host, making the restrictions unnecessary. For example, if the exact CPUs needed by an instance are not available on any compute host, a cold migration would fail. Without the workaround, a host would be found that can accept the instance by recalculating its CPU pinning.

You can disable this workaround by setting cpu_pinning_migration_quick_fail to False. With the quick-fail workaround disabled, live migration with CPU pinning reverts to the upstream behavior, but the restrictions are lifted from all other move operations, allowing them to work correctly.