deb-cinder/releasenotes/notes/add-stochastic-scheduling-option-99e10eae023fbcca.yaml
Ben Swartzlander de66e8f811 Add stochastic weight handler to scheduler
Add a config option to the scheduler host manager to select host
weight managers other than the default. Rename the existing default
weight manager TopHostWeightHandler because its behavior is to
always choose the top weight. Add a new weight manager which
randomly chooses the host using weights as probabilities.

DocImpact

Implements blueprint stochastic-weighing-scheduler

Change-Id: Ie5985066e68aef25600f8b76948adacd4c04263a
2016-08-02 20:16:01 +00:00

12 lines
606 B
YAML

---
features:
- Added a new config option `scheduler_weight_handler`. This is a global
option which specifies how the scheduler should choose from a listed of
weighted pools. By default the existing weigher is used which always
chooses the highest weight.
- Added a new weight handler `StochasticHostWeightHandler`. This weight
handler chooses pools randomly, where the random probabilities are
proportional to the weights, so higher weighted pools are chosen more
frequently, but not all the time. This weight handler spreads new
shares across available pools more fairly.