How to set up hardware preference for a given PCI board?

asked 2016-12-01 07:58:36 -0600

gomgom gravatar image

updated 2016-12-02 07:27:12 -0600


I'm a complete newbie, so I hope this question is not completely irrelevant. I'm still learning about the high level concepts in OpenStack, but have not found what I'm looking for so far.

We have an application which is optimized when running on a platform hosting a custom PCIe board. However it can also run without it, at a much lesser speed.

Is there a way to specify a preference for a given hardware, specifically servers hosting a given PCIe board, when assigning a VM to a server? The PCIe board in question is not a standard one, it is not a NIC or a graphic card.

If so, is the PCIe configuration for each server defined statically when they're installed by the site admin, or is there a module which takes care of discovering a server's configuration, and publishing it to Nova or whichever element is going to schedule VM deployment in this case?


edit retag flag offensive close merge delete

1 answer

Sort by ยป oldest newest most voted

answered 2016-12-02 07:26:41 -0600

gomgom gravatar image

OK, I guess I found some elements today, but still don't have answers to my problem.

My understanding is that the resource assignment will be done by Nova. The filter ComputeCapabilitiesFilter can be extended to add pretty much any type of custom capability, as an extra_specs field. This filter could be used to select servers hosting custom hardware.

However I am still not clear on the following:

  • my understanding is that the extra_specs attribute of each host is set manually by the admin. I'm looking for an automatic way of detecting, and updating hardware status (to account for hot swappable boards), so that each server would publish their configuration on a regular basis
  • the filter mechanism can filter out hosts, and ensure that a VM is instantiated on the proper hardware. But what if my VM's requirements vary, depending on the presence of my PCI board? It is takes 1 core, 2G or RAM with the PCI board, and 4 cores, 16G without it? Is there a way of modelling this type of dual requirement?
edit flag offensive delete link more

Get to know Ask OpenStack

Resources for moderators

Question Tools

1 follower


Asked: 2016-12-01 07:58:36 -0600

Seen: 50 times

Last updated: Dec 02 '16