Gnocchi Charm

Storage of metrics in an OpenStack Cloud is a big data problem.

Ceilometer has used MongoDB since its initiation for storage of measures; however this has not proven scalable, and the telemetry project have moved to a default of using Gnocchi (a spin out of the telemetry project) for storage of measures.

We need to charm Gnocchi to allow OpenStack Operators to deploy and use telemetry services as part of an OpenStack cloud.

Problem Description

Gnocchi is a multi-tenant timeseries, metrics and resources database. It provides an HTTP REST interface to create and manipulate the data. It is designed to store metrics at a very large scale while providing access to metrics and resources information and history.

Proposed Change

The new Gnocchi charm should include, as a minimum, the following features:

  • Deployable in a highly available configuration

  • Allow clients and services to interact using SSL encryption

  • Charm progress displayed via workload status

The charm will use the default storage options:

  • Storage driver: Ceph (preferred)

  • Indexing driver: MySQL (not preferred but default for rest of OpenStack)

  • Coordination: Memcache (zookeeper and redis are alternative options)

The choice of coordination driver is limited to memcache, zookeeper or redis as these drivers support the required features for Gnocchi.

The Gnocchi charm will support OpenStack Mitaka and later on Ubuntu 16.04.

Graphical reporting for Ceilometer was dropped from Horizon during Ocata; the telemetry stack will make use of the Grafana Charm + the Gnocchi Plugin for graphical reporting on Gnocchi metrics.

Alternatives

None.

Implementation

Assignee(s)

Primary assignee:

jamespage

Gerrit Topic

Use Gerrit topic “gnocchi-charm” for all patches related to this spec.

git-review -t gnocchi-charm

Work Items

Reactive Interfaces

  • interface: gnocchi

Provide Gnocchi charm

  • Create skeleton charm layer based on OpenStack base layer and available interface layers to deploy Gnocchi.

  • Add support for upgrading Gnocchi

  • Add config option and accompanying support for upgrades via action-managed-upgrade.

  • Add support for deploying Gnocchi in a highly available configuration

  • Add support for the Gnocchi to display workload status

  • Add support SSL endpoints

  • Charm should have unit and functional tests.

Update Ceilometer and Aodh charms

  • Support for deployment with Gnocchi

Mojo specification deploying and testing Gnocchi

  • Update HA Mojo spec for deploying Gnocchi in an HA configuration.

Update telemetry bundle

  • Update telemetry bundle to deploy Gnocchi and Grafana.

Repositories

A new git repository will be required for the Gnocchi charm:

https://git.openstack.org/openstack/charm-gnocchi

Documentation

The Gnocchi charm should contain a README with instructions on deploying the charm. A blog post is optional but would be a useful addition.

Security

No additional security concerns.

Testing

Code changes will be covered by unit tests; functional testing will be done using a combination of Amulet, Bundle tester and Mojo specification.

Dependencies

  • No dependencies outside of this specification.