feature: add option to control whether scraping go_collector mertics is disabled

[stanxing]

When I run the program and visit /metrics, I found they includes many go_collector metrics. This has nothing to do with php_fpm and can not be disabled. Mybe someone think it is helpful to debug exporter self. But I feel they are noise and take up a lot of space. So may be should have a flag to control whether this behavior is enabled.

➜ curl http://localhost:9253/metrics                   
# HELP go_gc_duration_seconds A summary of the pause duration of garbage collection cycles.
# TYPE go_gc_duration_seconds summary
go_gc_duration_seconds{quantile="0"} 0
go_gc_duration_seconds{quantile="0.25"} 0
go_gc_duration_seconds{quantile="0.5"} 0
go_gc_duration_seconds{quantile="0.75"} 0
go_gc_duration_seconds{quantile="1"} 0
go_gc_duration_seconds_sum 0
go_gc_duration_seconds_count 0
# HELP go_goroutines Number of goroutines that currently exist.
# TYPE go_goroutines gauge

...

[estahn]

After some research, there seems to be a consensus that this is useful. I would accept a PR for this.

I suggest naming the parameter web.disable-exporter-metrics to keep the same standard used in node-exporter.

                disableExporterMetrics = kingpin.Flag(
                        "web.disable-exporter-metrics",
                        "Exclude metrics about the exporter itself (promhttp_*, process_*, go_*).",
                ).Bool()

References:

• https://github.com/prometheus/node_exporter/pull/1148

[stanxing]

@estahn PR linked

[stale[bot]]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[mingalevme]

@estahn Why PR hasn't been merged?

[mingalevme]

If someone needs the original repo with the PR:

https://gist.github.com/mingalevme/28642bf1160a760f024d5155259d32a4