Installation instructions for Google Managed Service for Prometheus
The following instructions assume that you are running Google Managed Service for Prometheus (GMP) in its managed collection mode and that you have installed krr.
krr depends upon 2 cAdvisor metrics:
container_cpu_usage_seconds_total
container_memory_working_set_bytes
In order for krr to work with GMP, we need to ensure that cAdvisor is enabled and that the GMP Operator is configured to collect these 2 metrics. This can be combined into a single step that involves revising the GMP Operator configuration file operatorconfig/config
in Namespace gmp-public
Google provides instructions for enabling Kubelet/cAdvisor. This requires adding a kubeletScraping
section to the configuration file.
We must also add a filter
section to the configuration file. The filter
matches the 2 metrics that krr uses.
operatorconfig.krr.patch.yaml
:
collection:
filter:
matchOneOf:
- '{__name__="container_cpu_usage_seconds_total"}'
- '{__name__="container_memory_working_set_bytes"}'
kubeletScraping:
interval: 30s
There are various ways to make this Resource change to the cluster.
You can kubectl edit
the file and manually add the changes:
KUBE_EDITOR="nano" \
kubectl edit operatorconfig/config \
--namespace=gmp-public
Or you can kubectl patch
the file:
kubectl patch operatorconfig/config \
--namespace=gmp-public \
--type=merge \
--patch-file=/path/to/operatorconfig.krr.patch.yaml
There are multiple ways to confirm that GMP is collecting the metrics needed by krr.
The simplest is to access Google Cloud Console "Metric Diagnostics" and confirm that the "Metrics" section includes the 2 metrics with (recent) "Metric Data Ingested":
https://console.cloud.google.com/monitoring/metrics-diagnostics?project={project}
NOTE Replace
{project}
with your Google Cloud Project ID.
Another way is to deploy the Frontend UI for GMP and use the UI to browse the metrics.
GMP implements the Prometheus HTTP API and, like krr, we can use this to query the metrics:
PROJECT="..." # Google Cloud Project ID
MONITORING="https://monitoring.googleapis.com/v1"
ENDPOINT="${MONITORING}/projects/${PROJECT}/location/global/prometheus"
TOKEN=$(gcloud auth print-access-token)
# Either
QUERY="count({__name__=\"container_cpu_usage_seconds_total\"})"
# Or
QUERY="count({__name__=\"container_memory_working_set_bytes\"})"
curl \
--silent \
--get \
--header "Authorization: Bearer ${TOKEN}" \
--data-urlencode "query=${QUERY}" \
${ENDPOINT}/api/v1/query
If you have jq installed, you can filter the results to output only the latest value:
| jq -r .data.result[0].value[1]
krr leverages Google Application Default Credentials (ADC). Ensure that ADC credentials are accessible (per Google's documentation) before running krr so that krr can authenticate to GMP.
PROJECT="..." # Google Cloud Project ID
MONITORING="https://monitoring.googleapis.com/v1"
ENDPOINT="${MONITORING}/projects/${PROJECT}/location/global/prometheus"
python krr.py simple \
--prometheus-url=${ENDPOINT}