performance degradation with gofish 1.14 and added redfish_manager_log metrics

[ulikl]

Hi,

we have seen a performance degradation for the exporter due to the introduction of redfish_manager_log and gofish upgrade to 1.14
from ca. 50seconds to over 2m.

Disabling the redfish_manager_log metrics gained 30seconds.
Is it possible to make the log metrics optional, as these are also quite a lot?

The main degradation is probably manly due to the concurrency changes and the default concurrency being 1.
see stmcginnis/gofish#261

See have tested with increasing the concurrency in
https://github.com/jenningsloy318/redfish_exporter/blob/master/collector/redfish_collector.go#L108

config := gofish.ClientConfig{
		Endpoint: url,
		Username: username,
		Password: password,
		Insecure: true,
		Endpoint:              url,
		Username:              username,
		Password:              password,
		Insecure:              true,
		MaxConcurrentRequests: 15,

Note: this need the latest gofish release 1.15.

With this we are back to the old runtimes.
We are still testing with concurrent calls of the redfish exporter.

Kind Regards,
Ulrike