Ceilometer is OpenStack's metering project that collects usage data from OpenStack components like Nova, Glance, and Cinder. It allows for single collection of per-user/tenant usage data across all resources. Ceilometer is designed to be scalable, provide a simple REST API, and be extensible via plugins. DreamHost plans to use Ceilometer to measure usage for billing by customizing it to track instance hours, storage, and bandwidth usage.

1. Doug Hellmann
aka doughellmann/dhellmann (twitter/irc)
doug.hellmann@dreamhost.com
Nick Barcet
aka nijaba (twitter/irc)
nick.barcet@canonical.com
Ceilometer
The OpenStack Metering Project
15 Oct 2012 @ ODS Grizzly

2. What About Billing?
● Billing has been left out of OpenStack core so far as it
was not the primary problem and is not a trivial one...
● Yet almost every OpenStack deployment needs a way
to track usage information

3. Billing: 3 Step Process
Metering Collect usage data
Rating Transform usage data into billable
items and calculate costs
Billing Create invoice, collect payment

4. Ceilometer is Metering
Usage data collection is the ONLY thing
common to all clouds

5. Uses for Metering
● Billing
● Auditing
● Capacity Planning

6. Problems to Solve
● Collecting per user/tenant usage data
○ For every resource
○ From every OpenStack component
○ In a single place
● Retrieving usage data
○ From a single place
● Doing this with an open source project
○ Everyone did this in their own corner in the past :-(

7. Ceilometer Begins
● Started in May 2012

8. Ceilometer Rises
● Developed in StackForge
○ Same process as OpenStack
● Minimal set of meters defined
● Targeting OpenStack core
○ incubation pending

9. Design Requirements
● Scalable
○ …if your database is too

10. Design Requirements
● Scalable
○ …if your database is too
● Message signature
○ Non-repudiation built in

11. Design Requirements
● Scalable
○ …if your database is too
● Message signature
○ Non-repudiation built in
● Only one entry point to get data

12. Design Requirements
● Scalable
○ …if your database is too
● Message signature
○ Non-repudiation built in
● Only one entry point to get data
● Extensible, add your own:
○ Agent
○ Agent plugin
○ Storage engine
○ Meters

13. Design Requirements
● Scalable
○ …if your database is too
● Message signature
○ Non-repudiation built in
● Only one entry point to get data
● Extensible, add your own:
○ Agent
○ Agent plugin
○ Storage engine
○ Meters
● Use openstack-common components

14. Design Requirements
● Scalable
○ …if your database is too
● Message signature
○ Non-repudiation built in
● Only one entry point to get data
● Extensible, add your own:
○ Agent
○ Agent plugin
○ Storage engine
○ Meters
● Use openstack-common components
● Accept data from many sources

15. Data Triggers
Ceilometer inputs are generated three ways
User Action Creating, modifying, or deleting a
resource
Audit Regular audit events stating usage
generated by the service
Polling The ceilometer agent asks the service
for data periodically

16. Meter Categories
Ceilometer handles 3 types of meters
Cumulative Increasing over time (instance hours)
Gauge Discrete items (floating IPs, image
uploads) and fluctuating values (disk
I/O)
Delta Changing over time (bandwidth)

23. Simple REST API
Sum GET /v1/resources/(resource)/meters/(meter)/volume/sum
Maximum GET /v1/resources/(resource)/meters/(meter)/volume/max
Duration GET /v1/resources/(resource)/meters/(meter)/duration
Raw Events GET /v1/resources/(resource)/meters/(meter)
http://ceilometer.readthedocs.org/en/latest/api.html

24. Roadmap
Folsom Grizzly H
● Delivered last week ● Incubated Project ● Core Project
● Collects base metering ● User accessible API? ● TBD
○ nova ● Integration example with
○ glance Horizon
○ cinder ● New agents for other
○ quantum openstack components
● Basic API access ○ Swift
○ Heat?
● New uses of collector?
● SQLAlchemy storage
driver

25. DreamHost Use Case
● New Public Cloud Service
● Existing Billing System
● Existing Users and Accounts

26. Configuring Ceilometer
● Measure exactly what we want to bill for
○ instance hours
○ block storage
○ image uploads
○ bandwidth

27. Customizing Ceilometer
● Custom Bandwidth Meter
○ No charge for traffic "inside" DreamHost
○ Don't expose infrastructure details to customers
○ Measure at the router, not the VIF

28. Consuming Meter Data

29. Questions?
http://launchpad.net/ceilometer
http://ceilometer.readthedocs.org
freenode: #openstack-metering
email: openstack-dev [ceilometer]
Doug Hellmann Nick Barcet
aka doughellmann/dhellmann (twitter/irc) aka nijaba (twitter/irc)
doug.hellmann@dreamhost.com nick.barcet@canonical.com