status-go/metrics
Andrea Maria Piana 4685b9eaa9 Handle deadlock in peerpool
There was another deadlock in the peer pool.
Because we made the event handler asynchrnous, another deadlock popped
up, as the loop locks the global peerpool lock before processing events.
But the handlers also take the global look, effectively resulting in the
same situation we had before, i.e the loop is not running.

THE LOOP MUST BE RUNNING AT ALL TIMES OTHERWISE THE SERVER HANGS.
2021-02-02 07:58:17 +01:00
..
node Handle deadlock in peerpool 2021-02-02 07:58:17 +01:00
README.md add README for metrics (#1906) 2020-03-17 22:09:21 +01:00
metrics.go add a simple healtcheck for metrics endpoint 2019-11-04 16:29:14 +01:00

README.md

Description

This package configures Prometheus metrics for the node.

Technical Details

We use a trick to combine our metrics with Geth ones.

The NewMetricsServer() function in metrics.go calls our own Handler() function which in turn calls two handlers:

  • promhttp.HandlerFor() - Our own custom metrics from this package.
  • gethprom.Handler(reg) - Geth metrics defined in metrics

By calling both we can extend existing metrics.

Metrics

We add a few extra metrics on top of the normal Geth ones in node/metrics.go:

  • p2p_peers_count - Current numbers of peers split by name.
  • p2p_peers_absolute - Absolute number of connected peers.
  • p2p_peers_max - Maximum number of peers that can connect.

The p2p_peers_count metrics includes 3 labels:

  • type - Set to StatusIM for mobile and Statusd for daemon.
  • version - Version of status-go, always with the v prefix.
  • platform - Host platform, like android-arm64 or darwin-arm64

The way this data is acquired is using node names, which look like this:

StatusIM/vrelease-0.30.1-beta.2/android-arm/go1.11.5
Statusd/v0.34.0-beta.3/linux-amd64/go1.13.1
Geth/v1.9.9-stable-5aa131ca/linux-amd64/go1.13.3

This 4 segment format is standard for Ethereum as you can see on https://ethstats.net/.

We parse the names using labelsFromNodeName() from node/metrics.go.

Links