Delay the init() of github.com/goccy/go-json

[ptodev]

PR Description

The github.com/goccy/go-json creates a cache in its init() function which takes about 20MB of memory. This happens even if no component uses this particular json library. There is a PR upstream to change the behaviour to a lazy initialisation, and other projects such as grafana/grafana have already been patched with a fork that does it.

I'm not 100% sure which features of which components use goccy/go-json, but I think it's these packages:

• Splunk HEC exporter
• Stanza
• OTTL

Notes to the Reviewer

This is a profile of a locally ran Alloy instance prior to the change:

This is a profile after the change:

This is its config:

otelcol.receiver.otlp "from_k6" {
    grpc {
        endpoint = "0.0.0.0:4320"
    }

    output {
    traces  = [otelcol.exporter.loadbalancing.default.input]
    }
}

otelcol.exporter.loadbalancing "default" {
  routing_key = "traceID"
    resolver {
        static {
            hostnames = ["localhost:55690"]
        }
    }
    protocol {
        otlp {
            client {
              tls {
                insecure = true
              }
            }
        }
    }
}

PR Checklist

• CHANGELOG.md updated
• Documentation added
• Tests updated
• Config converters updated

[wildum]

Awesome find, just a nit for the changelog entry

[mattdurham]

Seems reasonable and a well trod approach.