In our case we have specific Virtual Network Function images which require deployment with 1 NUMA node topology. Some of them require sr- iov ports and some not.
As from my point of view, NUMA scheduling could be more advanced and instance without pci device request should be placed on NUMA node with no PCI device attached. As example it could be an extra_spec for flavor to specify that guest NUMA nodes should be bind to host NUMA nodes with no associated with them PCI devices in pci_passthrough_whitelist ** Changed in: nova Status: Invalid => New -- 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/1614882 Title: NUMA node scheduling problem Status in OpenStack Compute (nova): New Bug description: Description =========== Instances without pci passthrough requests can overfill host NUMA nodes with dedicated for pci passthrough PCI devices. Instances placed on such NUMA nodes despite that there are plenty free resources in other host NUMA nodes. Such scheduling can lead to situation that further deployment of an instance with pci passthrough request will fail because of unavailable capacity in required NUMA node. Steps to reproduce ================== Test host with 2 NUMA nodes and PCI device attached to NUMA node 0. Create a flavor with hw:cpu_policy=dedicated Spawn several instances without pci passthrough with overall memory allocation equal memory capacity for NUMA node 0. Then deploy instance with sr-iov port. Scheduling fails with following error: 2016-08-18 11:17:15.470 55110 DEBUG nova.compute.manager [req-c6d96425 -e98b-4a63-8289-e56c40ac46d9 bb8e586fd1264034885fef3aae39e777 b770743f66c44840a999cc8cf60916cd - - -] [instance: b4470025-2a59-4772-9990-a96b55966214] Build of instance b4470025-2a59-4772-9990-a96b55966214 was re-scheduled: Insufficient compute resources: Requested instance NUMA topology together with requested PCI devices cannot fit the given host NUMA topology. _do_build_and_run_instance /usr/lib/python2.7/site- packages/nova/compute/manager.py:1945 Environment =========== Mitaka release Nova: 13.0.0 To manage notifications about this bug go to: https://bugs.launchpad.net/nova/+bug/1614882/+subscriptions -- Mailing list: https://launchpad.net/~yahoo-eng-team Post to : yahoo-eng-team@lists.launchpad.net Unsubscribe : https://launchpad.net/~yahoo-eng-team More help : https://help.launchpad.net/ListHelp