Output a dispersion report that shows how many parts have each replica count
at each tier along with some additional context. Also the max_dispersion is a
good canary for what a reasonable overload might be.
Also display a warning on rebalance if the ring's dispersion is sub-optimal.
The primitive form of the dispersion graph is cached on the builder, but the
dispersion command will build it on the fly if you have a ring that was last
rebalanced before the change.
Also add --force option to rebalance to make it write a ring even if less than
1% of parts moved.
Try to clarify some dispersion and balance a little bit in the ring section of
the architectural overview.
Co-Authored-By: Christian Schwede <christian.schwede@enovance.com>
Co-Authored-By: Darrell Bishop <darrell@swiftstack.com>
Change-Id: I7696df25d092fac56588080722e0a4167ed2c824
Fixed some grammar issues, formatting issues, clarrified some
wording now that its easier to read fully rendered.
Change-Id: Ie803dd1a84d50de7663a7099c32d81807701e188
Add overview and example information for using Storage Policies.
DocImpact
Implements: blueprint storage-policies
Change-Id: I6f11f7a1bdaa6f3defb3baa56a820050e5f727f1
