Open Stack

Hi All,

In next couple of days we will resume our PCI passthrough/SR-IOV proposal.
With the help from Cisco folks I'm sure we will be able to propose it
pretty soon.

I suppose that on the first stage it might be enough to use
instance_types's extra specs to specify what exactly should be assigned to
the instance. I don't think that cloud users should have a control about
what and when should be attached (for sure not physical USBs). IMHO,
having special instance types (like with X PCI devices of type Y or with
GPU, etc) will be enough.

We can easily propagate information about device availability to the
scheduler and on scheduler level to make a decision about proper host.

Regarding querying HW resources - we implemented it on host settings
level. Of course we can add something on virt driver level, but it will be
quite different per each installation type.

Regards,
-Vladimir


-----Original Message-----
From: Vishvananda Ishaya [mailto:vishvananda at gmail.com]
Sent: Thursday, November 01, 2012 11:22 AM
To: OpenStack Development Mailing List
Cc: Ian Wells; vladimir at zadarastorage.com
Subject: Re: [openstack-dev] Some idea on device assignment support


On Nov 1, 2012, at 8:39 AM, heut2008 <heut2008 at gmail.com> wrote:

>
> should  we create  a new table to  manage all these  devices? or  each
> nova-compute node manage their own devices allocation,if there is no
> new table to record this.  we need each kind of passthrough  devices
> has a driver to keep track of how many resources is free and how many
> is in use,  these info  is updated to schedule  by sending capability
> info periodly.

I would prefer to avoid adding new tables unless we have to. It seems like
the HostState class in host_manager needs to be able to support arbitrary
keys for counting resources. Then we could create filter and weighting
functions based on these arbitrary keys and update the consume method to
consume resources from these keys based on instance_type_extra_specs.

Perhaps we need some kind of compute_metadata. there is a compute stats
table which we might be able to abuse for this purpose.

Vish