Hashmap rating module

CloudKitty is shipped with core rating modules.

Hashmap composition

You can see hashmap as a simple tree:

digraph "Hashmap's data structure" { label="HashMap module data structure"; compound=true; compute; network [label="network.floating_ip"]; volume; subgraph cluster_0 { label="services"; style=dashed; {rank=same; compute -> network -> volume [style=invis];} } compute -> flavor; subgraph cluster_1 { label="fields:\nAssociate to metadata"; style=dashed; flavor; } // Mappings micro [label="value=m1.micro\ntype=flat\ncost=0.1"]; tiny [label="value=m1.tiny\ntype=flat\ncost=0.2"]; small [label="value=m1.small\ntype=flat\ncost=0.4"]; floating [label="\ntype=flat\ncost=0.5"]; // Thresholds 1024 [label="level=1024\ntype=flat\ncost=0.1"]; 10240 [label="level=10240\ntype=flat\ncost=0.2"]; subgraph cluster_2 { label="mappings"; style=dashed; {rank=same; micro -> tiny -> small -> floating [style=invis];} } subgraph cluster_3 { label="thresholds"; style=dashed; {rank=same; 1024 -> 10240 [style=invis];} } flavor -> micro; flavor -> tiny; flavor -> small; network -> floating; volume -> 1024; volume -> 10240; }

HashMap is composed of different resources and groups.

Group

A group is a way to group calculations of mappings. For example you might want to apply a set of rules to charge instance_uptime and another set to block storage volume. You don’t want the two to be linked so you’ll create one group for each calculation.

Service

A service is a way to map the rule to the type of data collected. Currently, the following services are available:

  • compute
  • image
  • volume
  • network.bw.in
  • network.bw.out
  • network.floating

Enabled services are defined in the configuration file. By default, only the compute service is enabled.

Field

A field is referring to a metadata field of a resource. For example on an instance object (compute), you can use the flavor to define specific rules.

With Ceilometer as the collector, the following fields are available for each service:

  • Compute: flavor, vcpus, memory (MB), image_id, availability_zone
  • Volume: name, volume_type, availability_zone
  • Image: disk_format, container_format, is_public, availability_zone

With Gnocchi as collector, the following fields are available for each service:

  • Compute: flavor_id, vcpus, image_id, memory (MB)
  • Image: container_format, disk_format

Mapping

A mapping is the final object, it’s what triggers calculation, for example a specific value of flavor on an instance. It maps cost to a value of metadata in case of field mapping. And directly a cost in case of service mapping.

A mapping can be project specific by providing a project id at creation and supports overloading, i.e. you can specify multiple mappings for the same value with different project ids and costs.

Threshold

A threshold entry is used to apply rating rules base on level. Its behaviour is similar to a mapping except that it applies the cost base on the level.

As for mapping, a threshold can be project specific by providing a project id at creation.

HashMap formula

Based on all the previous objects here’s the calculation formula : \(\sum_{n=1}^N G_n(qty.(T_{rate}\prod(M_{rate})(T_{flat}+M_{flat})))\)

G:Group
qty:Quantity of resource
T:Threshold
M:Mapping

For an active resource on a collection period, quantity is defined as follow:

  • compute: 1 (unit: instance)
  • image: upload image size (unit: MB)
  • volume: volume size (unit: GB)
  • network.bw.in: ingoing network usage (unit: MB)
  • network.bw.out: outgoing network usage (unit: MB)
  • network.floating: 1 (unit: ip)

Example

Compute uptime

Apply rating rule on the compute service to charge the instance based on it’s flavor and uptime:

Create a group instance_uptime_flavor:

$ cloudkitty hashmap-group-create -n instance_uptime_flavor
+----------+--------------------------------------+
| Property | Value                                |
+----------+--------------------------------------+
| group_id | 26d2d69a-4c42-47f1-9d44-2cdfad167f7d |
| name     | instance_uptime_flavor               |
+----------+--------------------------------------+

$ cloudkitty hashmap-group-list
+------------------------+--------------------------------------+
| Name                   | Group id                             |
+------------------------+--------------------------------------+
| instance_uptime_flavor | 26d2d69a-4c42-47f1-9d44-2cdfad167f7d |
+------------------------+--------------------------------------+

Create the service matching rule:

$ cloudkitty hashmap-service-create -n compute
+------------+--------------------------------------+
| Property   | Value                                |
+------------+--------------------------------------+
| name       | compute                              |
| service_id | 08ab2d27-fe95-400c-9602-e5ad5efdda8b |
+------------+--------------------------------------+

Create a field matching rule:

$ cloudkitty hashmap-field-create \
 -s 08ab2d27-fe95-400c-9602-e5ad5efdda8b -n flavor
+------------+--------------------------------------+
| Property   | Value                                |
+------------+--------------------------------------+
| field_id   | f37364af-6525-40fc-ae08-6d4087429862 |
| name       | flavor                               |
| service_id | 08ab2d27-fe95-400c-9602-e5ad5efdda8b |
+------------+--------------------------------------+

Create a mapping in the group instance_uptime_flavor that will map m1.tiny instance to a cost of 0.01:

$ cloudkitty hashmap-mapping-create \
 -f f37364af-6525-40fc-ae08-6d4087429862 \
 -v m1.tiny -t flat -c 0.01 -g 26d2d69a-4c42-47f1-9d44-2cdfad167f7d
+------------+--------------------------------------+
| Property   | Value                                |
+------------+--------------------------------------+
| cost       | 0.01                                 |
| field_id   | f37364af-6525-40fc-ae08-6d4087429862 |
| group_id   | 26d2d69a-4c42-47f1-9d44-2cdfad167f7d |
| mapping_id | df592a91-a6a5-41fa-ba2e-2f763eaa36e5 |
| service_id | None                                 |
| tenant_id  | None                                 |
| type       | flat                                 |
| value      | m1.tiny                              |
+------------+--------------------------------------+

In this example every machine in any project with the flavor m1.tiny will be charged 0.01 per collection period.

Volume per gb with discount

Now let’s do some threshold based rating.

Create a group volume_thresholds:

$ cloudkitty hashmap-group-create -n volume_thresholds
+----------+--------------------------------------+
| Property | Value                                |
+----------+--------------------------------------+
| group_id | dd3dc30e-0e63-11e6-9f83-ab4208c1fe2d |
| name     | volume_thresholds                    |
+----------+--------------------------------------+

$ cloudkitty hashmap-group-list
+-------------------+--------------------------------------+
| Name              | Group id                             |
+-------------------+--------------------------------------+
| volume_thresholds | dd3dc30e-0e63-11e6-9f83-ab4208c1fe2d |
+-------------------+--------------------------------------+

Create the service matching rule:

$ cloudkitty hashmap-service-create -n volume
+------------+--------------------------------------+
| Property   | Value                                |
+------------+--------------------------------------+
| name       | volume                               |
| service_id | 16a48060-0e64-11e6-8e4e-1b285514a36e |
+------------+--------------------------------------+

Now let’s setup the price per gigabyte:

$ cloudkitty hashmap-mapping-create \
 -s 16a48060-0e64-11e6-8e4e-1b285514a36e \
 -t flat -c 0.001 -g dd3dc30e-0e63-11e6-9f83-ab4208c1fe2d
+------------+--------------------------------------+
| Property   | Value                                |
+------------+--------------------------------------+
| cost       | 0.001                                |
| field_id   | None                                 |
| group_id   | dd3dc30e-0e63-11e6-9f83-ab4208c1fe2d |
| mapping_id | 41669786-240b-11e6-872c-af96ddb6619c |
| service_id | 16a48060-0e64-11e6-8e4e-1b285514a36e |
| tenant_id  | None                                 |
| type       | flat                                 |
| value      |                                      |
+------------+--------------------------------------+

We have the basic price per gigabyte be we now want to apply a discount on huge data volumes. Create the thresholds in the group volume_thresholds that will map different volume quantity to costs:

Here we set a threshold when going past 50GB, and apply a 2% discount (0.98):

$ cloudkitty hashmap-threshold-create \
 -s 16a48060-0e64-11e6-8e4e-1b285514a36e \
 -l 50 -t rate -c 0.98 -g dd3dc30e-0e63-11e6-9f83-ab4208c1fe2d
+--------------+--------------------------------------+
| Property     | Value                                |
+--------------+--------------------------------------+
| cost         | 0.98                                 |
| field_id     | None                                 |
| group_id     | dd3dc30e-0e63-11e6-9f83-ab4208c1fe2d |
| level        | 50                                   |
| threshold_id | 8eb45bfc-0e64-11e6-ad0e-07a62425f284 |
| service_id   | 16a48060-0e64-11e6-8e4e-1b285514a36e |
| tenant_id    | None                                 |
| type         | rate                                 |
+--------------+--------------------------------------+

Here we set the same threshold for project 8f1e8645a0e7496a95a4fdf4b2795b2c but with a 3% discount (0.97):

$ cloudkitty hashmap-threshold-create \
 -s 16a48060-0e64-11e6-8e4e-1b285514a36e \
 -l 50 -t rate -c 0.98 -g dd3dc30e-0e63-11e6-9f83-ab4208c1fe2d \
 -p 8f1e8645a0e7496a95a4fdf4b2795b2c
+--------------+--------------------------------------+
| Property     | Value                                |
+--------------+--------------------------------------+
| cost         | 0.97                                 |
| field_id     | None                                 |
| group_id     | dd3dc30e-0e63-11e6-9f83-ab4208c1fe2d |
| level        | 50                                   |
| threshold_id | 8eb45bfc-0e64-11e6-ad0e-07a62425f284 |
| service_id   | 16a48060-0e64-11e6-8e4e-1b285514a36e |
| tenant_id    | 8f1e8645a0e7496a95a4fdf4b2795b2c     |
| type         | rate                                 |
+--------------+--------------------------------------+

Here we set a threshold when going past 200GB, and apply a 5% discount (0.95):

$ cloudkitty hashmap-threshold-create \
 -s 16a48060-0e64-11e6-8e4e-1b285514a36e \
 -l 200 -t rate -c 0.95 -g dd3dc30e-0e63-11e6-9f83-ab4208c1fe2d
+--------------+--------------------------------------+
| Property     | Value                                |
+--------------+--------------------------------------+
| cost         | 0.95                                 |
| field_id     | None                                 |
| group_id     | dd3dc30e-0e63-11e6-9f83-ab4208c1fe2d |
| level        | 200                                  |
| threshold_id | baf180c8-0e64-11e6-abb3-cbae153a6d44 |
| service_id   | 16a48060-0e64-11e6-8e4e-1b285514a36e |
| tenant_id    | None                                 |
| type         | rate                                 |
+--------------+--------------------------------------+

In this example every volume is charged 0.01 per GB but if the size goes past 50GB you’ll get a 2% discount, if you even go further you’ll get 5% discount (only one level apply at a time).

For project 8f1e8645a0e7496a95a4fdf4b2795b2c only, you’ll get a 3% discount instead of 2% when the size goes past 50GB and the same %5 discount it it goes further.

20GB:0.02 per collection period.
50GB:0.049 per collection period (0.0485 for project 8f1e8645a0e7496a95a4fdf4b2795b2c).
80GB:0.0784 per collection period (0.0776 for project 8f1e8645a0e7496a95a4fdf4b2795b2c).
250GB:0.2375 per collection period.