[ElasticAPM] The limit of 1000 metricsets has been reached, no new metricsets will be created

[maxymvlasov (Maksym Vlasov)]

Elasticsearch version:
7.7.1
APM Server version:
7.6.2
APM Agent language and version:
Ruby
elastic-apm (3.7.0)
concurrent-ruby (~> 1.0)
http (>= 3.0)

Description of the problem including expected versus actual behavior. Please include screenshots (if relevant):
I would like understand what is it.

Here warning in code
And constant set

Provide logs and/or server output (if relevant):

W, [2020-06-10T21:55:16.640015 #91] WARN -- : [ElasticAPM] The limit of 1000 metricsets has been reached, no new metricsets will be created.
W, [2020-06-10T22:13:43.154728 #79] WARN -- : [ElasticAPM] The limit of 1000 metricsets has been reached, no new metricsets will be created.
W, [2020-06-10T22:15:52.308064 #67] WARN -- : [ElasticAPM] The limit of 1000 metricsets has been reached, no new metricsets will be created.

[mikker (Mikkel Malmberg)]

Hi Maksym.

This relates to the metrics and how many distinct metrics keys the agent will record. Every transaction and span kind translate to its own key. If you have many differently named endpoints for example, you'll end up with many different keys.

The limit is there to prevent a case where you'd have infinite keys.

Right now the limit is hardcoded but I suppose it makes sense to make it configurable.

I'll discuss it internally and get back to you.