perf: Benchmarks for OTLP conversion

[cijothomas]

Mostly to get a baseline of where is time being spent. That should help guide future perf optimizations.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 82.8%. Comparing base (dfdc478) to head (b63fd90).

Additional details and impacted files

@@          Coverage Diff          @@
##            main   #3307   +/-   ##
=====================================
  Coverage   82.8%   82.8%           
=====================================
  Files        130     130           
  Lines      27289   27289           
=====================================
  Hits       22622   22622           
  Misses      4667    4667           

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[scottgerring]

I note that the benchmark suite is failing I think because libopenssl is missing from the machines now. @trask I don't know if you happen to know if something happened to those runners (or if maybe we added new ones?)

https://github.com/open-telemetry/opentelemetry-rust/actions/runs/22340134406/job/64950532919?pr=3307

[trask]

I note that the benchmark suite is failing I think because libopenssl is missing from the machines now. @trask I don't know if you happen to know if something happened to those runners (or if maybe we added new ones?)

https://github.com/open-telemetry/opentelemetry-rust/actions/runs/22340134406/job/64950532919?pr=3307

hm, not sure, I don't think anyone has done anything recently (other than reboot it from time to time)

can you open a new community issue for tracking and link to the original one (to help me remember what I did before 😄)

[scottgerring]

I note that the benchmark suite is failing I think because libopenssl is missing from the machines now. @trask I don't know if you happen to know if something happened to those runners (or if maybe we added new ones?)
https://github.com/open-telemetry/opentelemetry-rust/actions/runs/22340134406/job/64950532919?pr=3307

hm, not sure, I don't think anyone has done anything recently (other than reboot it from time to time)

can you open a new community issue for tracking and link to the original one (to help me remember what I did before 😄)

Done - #3296 - thanks!
It could also be we didn't used to depend on this for our benchmark suite but i'm uncertain.

[github-actions]

Thank you for your contribution! This PR has been automatically marked as stale because it has not had activity in the last 14 days. This may be due to a delay in review on our side or awaiting a response from you; either is fine, and we appreciate your patience.

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[scottgerring]

Hey @cijothomas had a quick look at this because of the benchmark failures - I think what is going on is that opentelemetry-prometheus is using its own benchmark harness, which is not criterion but rather the normal rust one. So it doesn't understand --save-baseline. I think we should line that crate up with the criterion usage otherwise to get it going again. I think this is also going to break on main for the period checking as it stands.