Open Stack

On 7 February 2014 23:02, Taurus Cheung <Taurus.Cheung at harmonicinc.com> wrote:
> Hi,
>
>
>
> I am working on deploying images to bare-metal machines using nova
> bare-metal. In existing implementation in nova-baremetal-deploy-helper.py,
> there's only 1 worker to write image to bare-metal machines. If there is a
> number of bare-metal instances to deploy, they need to queue up and wait to
> be served by the single worker. Would the future implementation be improved
> to support multiple workers?

I think we'd all like to do multiple deploys at once, but there are
significant thrashing risks in just running concurrent dd's - for
instance, datacentre networks are faster than single disks (so
cloud-scale architectures have - paradoxically to most folk :)) more
network bandwidth than persistent IO bandwidth. In fact this patch
(https://review.openstack.org/#/c/71219/) reduces a source of
thrashing (based on testing on our prod hardware) to improve overall
performance.

Longer term with Ironic I can see multicast/bittorrent/that sort of
thing being used to achieve efficient concurrency when deploying many
identical images.

-Rob

-- 
Robert Collins <rbtcollins at hp.com>
Distinguished Technologist
HP Converged Cloud