cinder/releasenotes/notes/add-stochastic-scheduling-option-99e10eae023fbcca.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.
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 2016-07-22 14:04:59 -04:00			`---`
			`features:`
Fix release notes formatting We use double ticks to format config options, driver FQNs etc. in few release notes to improve readability. This patch updates the remaining release notes to follow the same convention. Change-Id: Ied4e5e02cc781405206edc2322567e5e5e3e170f 2016-09-13 10:54:00 +05:30			- Added a new config option ``scheduler_weight_handler``. This is a global
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 2016-07-22 14:04:59 -04:00			`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.`
Fix release notes formatting We use double ticks to format config options, driver FQNs etc. in few release notes to improve readability. This patch updates the remaining release notes to follow the same convention. Change-Id: Ied4e5e02cc781405206edc2322567e5e5e3e170f 2016-09-13 10:54:00 +05:30			- Added a new weight handler ``StochasticHostWeightHandler``. This weight
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 2016-07-22 14:04:59 -04:00			`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.`