cinder/releasenotes/notes/rbd-stats-report-0c7e803bb0b1aedb.yaml
Gorka Eguileor 8469109016 RBD: Fix stats reporting
Current RBD code is incorrectly reporting the stats of the pool in the
following ways:

- `provisioned_capacity_gb` contains physical space used by cinder created
  volumes.
- `free_capacity_gb` is not taking into account that pools can have quota
  restrictions and they should be used as the reference for the free capacity.
- `total_capacity` dynamically changes, which means that there is no way to
  have a fixed over provisioning capacity.

This patch fixes the stats reporting making sure we return the right
values in `provisioned_capacity_gb` and `free_capacity_gb`, and allows
us to use a static calculation of the `total_capacity` using
`report_dynamic_total_capacity` configuration option.

We don't report `allocated_capacity_gb` because this is something that
is calculated by the Cinder core code and should not be reported by
drivers, even if it's not currently working as expected [1][2].

[1] https://bugs.launchpad.net/cinder/+bug/1712549
[2] https://bugs.launchpad.net/cinder/+bug/1706057

Change-Id: I1e82bf9d0b6cc0fb1d1fc2dd8b8ccc59aea3f73f
Closes-Bug: #1706060
2017-08-23 14:33:27 +02:00

19 lines
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YAML

---
features:
- |
RBD driver supports returning a static total capacity value instead of a
dynamic value like it's been doing. Configurable with
`report_dynamic_total_capacity` configuration option.
upgrade:
- |
RBD/Ceph backends should adjust `max_over_subscription_ratio` to take into
account that the driver is no longer reporting volume's physical usage but
it's provisioned size.
fixes:
- |
RBD stats report has been fixed, now properly reports
`allocated_capacity_gb` and `provisioned_capacity_gb` with the sum of the
sizes of the volumes (not physical sizes) for volumes created by Cinder and
all available in the pool respectively. Free capacity will now properly
handle quota size restrictions of the pool.