Monitoring Functions

    The http_request* metrics record the latency and statistics of /system/* routes to monitor the OpenFaaS gateway and its provider. The /async-function route is also recorded in these metrics to observe asynchronous ingestion rate and latency.

    These basic metrics can be used to track the health of your functions as well a general usage patterns. See the Prometheus documentation and for more details about the available options and query functions. Below are several queries you might want to include in a basic Grafana dashboard for observing your OpenFaaS functions

    Function replica count / scaling

    Return the total function replicas:

    Return the total number of successful function invocations:

    Function execution time

    Each of the metrics generated by the Gateway are labeled with and can be filtered by the function name, For example The invocation rate for just a single function (e.g. if the function name is echo) is given by

    The classic and of-watchdog both provide Prometheus instrumentation on TCP port 8081 on the path /metrics. This is to enable the use-case of HPAv2 from the Kubernetes ecosystem.

    MetricTypeDescriptionLabels
    http_request_duration_secondshistogramSeconds spent serving HTTP requests, path, status
    http_requests_totalcounterThe total number of HTTP requestsmethod, path, status

    Minimum watchdog versions

    The metrics endpoint was added in the following versions and is enabled automatically.

    • watchdog: 0.13.0
    • of-watchdog 0.5.0