79 lines
3 KiB
Markdown
79 lines
3 KiB
Markdown
---
|
|
stage: Monitor
|
|
group: Health
|
|
info: To determine the technical writer assigned to the Stage/Group associated with this page, see https://about.gitlab.com/handbook/engineering/ux/technical-writing/#designated-technical-writers
|
|
---
|
|
|
|
# Working with Prometheus Metrics
|
|
|
|
## Adding to the library
|
|
|
|
We strive to support the 2-4 most important metrics for each common system service that supports Prometheus. If you are looking for support for a particular exporter which has not yet been added to the library, additions can be made [to the `common_metrics.yml`](https://gitlab.com/gitlab-org/gitlab/blob/master/config/prometheus/common_metrics.yml) file.
|
|
|
|
### Query identifier
|
|
|
|
The requirement for adding a new metric is to make each query to have an unique identifier which is used to update the metric later when changed:
|
|
|
|
```yaml
|
|
- group: Response metrics (NGINX Ingress)
|
|
metrics:
|
|
- title: "Throughput"
|
|
y_axis:
|
|
name: "Requests / Sec"
|
|
format: "number"
|
|
precision: 2
|
|
queries:
|
|
- id: response_metrics_nginx_ingress_throughput_status_code
|
|
query_range: 'sum(rate(nginx_upstream_responses_total{upstream=~"%{kube_namespace}-%{ci_environment_slug}-.*"}[2m])) by (status_code)'
|
|
unit: req / sec
|
|
label: Status Code
|
|
```
|
|
|
|
### Update existing metrics
|
|
|
|
After you add or change an existing common metric, you must [re-run the import script](../administration/raketasks/maintenance.md#import-common-metrics) that will query and update all existing metrics.
|
|
|
|
Or, you can create a database migration:
|
|
|
|
```ruby
|
|
class ImportCommonMetrics < ActiveRecord::Migration[4.2]
|
|
include Gitlab::Database::MigrationHelpers
|
|
|
|
DOWNTIME = false
|
|
|
|
def up
|
|
::Gitlab::DatabaseImporters::CommonMetrics::Importer.new.execute
|
|
end
|
|
|
|
def down
|
|
# no-op
|
|
end
|
|
end
|
|
```
|
|
|
|
If a query metric (which is identified by `id:`) is removed it will not be removed from database by default.
|
|
You might want to add additional database migration that makes a decision what to do with removed one.
|
|
For example: you might be interested in migrating all dependent data to a different metric.
|
|
|
|
## GitLab Prometheus metrics
|
|
|
|
GitLab provides [Prometheus metrics](../administration/monitoring/prometheus/gitlab_metrics.md)
|
|
to monitor itself.
|
|
|
|
### Adding a new metric
|
|
|
|
This section describes how to add new metrics for self-monitoring
|
|
([example](https://gitlab.com/gitlab-org/gitlab/-/merge_requests/15440)).
|
|
|
|
1. Select the [type of metric](https://gitlab.com/gitlab-org/prometheus-client-mmap#metrics):
|
|
|
|
- `Gitlab::Metrics.counter`
|
|
- `Gitlab::Metrics.gauge`
|
|
- `Gitlab::Metrics.histogram`
|
|
- `Gitlab::Metrics.summary`
|
|
|
|
1. Select the appropriate name for your metric. Refer to the guidelines
|
|
for [Prometheus metric names](https://prometheus.io/docs/practices/naming/#metric-names).
|
|
1. Update the list of [GitLab Prometheus metrics](../administration/monitoring/prometheus/gitlab_metrics.md).
|
|
1. Trigger the relevant page/code that will record the new metric.
|
|
1. Check that the new metric appears at `/-/metrics`.
|