[BUG] ETSCronFlusher high memory consumption and binaries leak

[IIILSW]

Describe the bug
We have registered high memory consumption by the ETSCronFlusher process heap and large number of attached ref binaries.

In the course of our experiments, abandoning the use of Exporter and placing the process in hibernate after cleanup allowed us to reduce memory consumption under load by ~70mb

To Reproduce
Memory consumption increases steadily as the number of metrics and load increases (4k rps in our case)

Expected behavior
A clear and concise description of what you expected to happen.

Environment

• Elixir version: 1.14.4
• Erlang/OTP version: 25.3
• Grafana version: -
• Prometheus version: -

Additional context
Created PRs in prom_ex and telemetry_metrics_prometheus_core #55

[akoutmos]

This may fix the issue and will not require any changes to prometheus_core #200

[nthouliss]

Is it possible to get a published version with this patch? I had the same issue and this patch resolved it.

[weisslj]

@akoutmos same for us, we would really like to have a new version of prom_ex that includes this bug fix 🙏

[akoutmos]

Added this to my todo list for tomorrow! Sorry for the delay!

[akoutmos]

It has been done! Download version 1.9.0 for the fix 😄