Description

Fixes the bug where async instruments' aggregations were not being reset after each collection interval. Since they observe a total value, they should be reset each collection. For example

def total_number_of_processes_callback() -> Iterable[Measurement]:
    yield Measurement(get_current_cpu_time())

meter.create_observable_counter(
  "system_processes_count",
  cpu_time_callback,
  description="The total number of processes that have run on this machine",
)

The SDK would report the wrong values like so:

This PR fixes it so we correctly report the total num processes.

Type of change

Please delete options that are not relevant.

• Bug fix (non-breaking change which fixes an issue)

How Has This Been Tested?

Updated tests to capture behavior. Also manually tested with prometheus and scraping /proc/stat

Does This PR Require a Contrib Repo Change?

• No.

Checklist:

• Followed the style guidelines of this project
• Unit tests have been added