Hi all,
I'd appreciate if the experts can point me in one direction or another. If
there are existing mechanisms, we don't want to reinvent the wheel. If there
aren't, I'd be interested in exploring clean ways to extend and enhance nova
scheduling.
Thank you very much.
Cheers,
Sundar
From: Sundar Nadathur
Sent: Monday, August 24, 2015 10:48 PM
To: '[email protected]'
Subject: [Nova] Placing VMs based on multiple criteria
Hi,
Please advise me whether the following scenario requires changes to nova
scheduler or can be handled with existing scheduling mechanisms.
I have a type of PCIe device (not necessarily a NIC or HBA). The device can be
configured with a set of user-defined resources - say A, B, C. Each resource
can be shared between a limited number of VMs -- say A can be shared among 4
VMs, B among 8, etc. A VM image may request the need for a specific list of
features, say A and B. Then I want to place the VM on a host according to these
criteria:
1. If there are hosts with a PCIe device that already has A and B
configured, and has a free instance each of A and B, the VM must be placed on
one of those hosts.
2. Otherwise, find a host with this PCIe device that can be configured
with one instance each of A and B.
It is not clear that this can be handled through 3rd party metadata. Suppose we
create host aggregates with properties like "resource=A" and "resource=B", and
also associate properties like "resource=A" with VM images. (A and B are UUIDs
representing user-defined resources.) Perhaps Nova scheduler can match the
properties to select host aggregates that have all properties that the VM
requires. However:
a. This would not be dynamic (i.e. track the free instances of each
resource), and
b. This addresses only #1 above.
Is there any way I can leverage existing scheduler mechanisms to solve this VM
placement problem? If not, do you have thoughts/comments on what changes are
needed?
Thanks, and apologies in advance if I am not clear. Please feel free to ask
questions.
Cheers,
Sundar
________________________________
Confidentiality Notice.
This message may contain information that is confidential or otherwise
protected from disclosure. If you are not the intended recipient, you are
hereby notified that any use, disclosure, dissemination, distribution, or
copying of this message, or any attachments, is strictly prohibited. If you
have received this message in error, please advise the sender by reply e-mail,
and delete the message and any attachments. Thank you.
__________________________________________________________________________
OpenStack Development Mailing List (not for usage questions)
Unsubscribe: [email protected]?subject:unsubscribe
http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev
