Open Stack

On 11 November 2013 12:04, Alexander Kuznetsov <akuznetsov at mirantis.com> wrote:
> Hi all,
>
> While studying Hadoop performance in a virtual environment, I found an
> interesting problem with Nova scheduling. In OpenStack cluster, we have
> overcommit policy, allowing to put on one compute more vms than resources
> available for them. While it might be suitable for general types of
> workload, this is definitely not the case for Hadoop clusters, which usually
> consume 100% of system resources.
>
> Is there any way to tell Nova to schedule specific instances (the ones which
> consume 100% of system resources) without overcommitting resources on
> compute node?

You could have a flavor with "no-overcommit" extra spec, and modify
the over-commit calculation in the scheduler on that case, but I don't
remember seeing that in there.

John