slider has an anti-affinity flag in roles (visible in resources.json?), which is ignored.
YARN-1042 promises this for YARN, slider will need
- flag in resources.json
- use in container requests
we may also want two policies: anti-affinity-desired, and -required. Then if required nodes get >1 container for the same component type on the same node, it'd have to request a new one and return the old one (Risk: getting the same one back).