faas-monitor

faas-monitor application periodically retrieve OpenFaaS functions metrics (such as response time, throughput, CPU utilization and more) and publish them to NATS included by default in OpenFaaS.

Available metrics

Function number of replicas
Function invocation rate
Function average response time
Function average processing time
Function average cold start time
Function throughput
Function nodes
Per replica CPU utilization
Per replica memory utilization

Architecture

faas-monitor makes use of available API of Prometheus, Kubernetes Metrics Server and API Server, and OpenFaaS gateway in order to get the most relevant functions' metrics.

Getting Started

Prerequisites

Before trying out this project make sure you have installed OpenFaaS on your kubernetes cluster.

Deploy your functions with the prometheus.io.scrape=true prometheus.io.port=8081 annotations if you are interested in the processing time metric.

Deployment

Edit deployment file in order to match components hostnames and set your preferred scrape period.

        ...

        env:
            - name: SCRAPE_PERIOD
              value: "60"
            - name: PROMETHEUS_URL
              value: "http://prometheus.openfaas:9090"
            - name: GATEWAY_URL
              value: "http://gateway.openfaas:8080"
            - name: NATS_URL
              value: "http://nats.openfaas:4222"
            - name: NATS_SUBJECT
              value: "metrics"

Deploy the application in a kubernetes cluster as follows: