Lagerist is a daemon that runs kernel traces to gather disk IO statistics, which are exposed as Histograms in the Prometheus format. The result, when graphed using the Grafana dashboard attached, looks like this:

Easiest via Docker:

docker run -d --name lagerist \
    --privileged \
    -v /proc:/proc \
    -v /dev:/dev:ro \
    -v /sys:/sys \
    -p 9789:9789 \
    svedrin/lagerist:latest