Mark out-of-order as stable

[jesusvazquez]

Proposal

Out-of-order has been out for a year now, and we've gained enough production experience to consider it as a stable feature.

Also out-of-order is a downstream dependency of OTEL Support because of how OTEL clients interact with Prometheus so as part of the initiative to have a better OTEL Support we need to mark this feature as stable.

Related issues

• Out-of-order post merge cleanup #11329
• Reuse the postings index when head and ooo head are overlapped #11628
• Perf: reuse postings when the head and the OOO head fall into the same query range #11644
• Simplify chunks.Meta by removing the OOO fields #11837
• refactor: markers related to OOO fields for tracking last added chunk (Post-merge cleanup) #12133
• TSDB: Provide an commit interface that does not write OOO samples #11730
• Nice to have:
  • Remove OOO Head compaction's dependency on the in-order Head compaction #11834
    • Scheduled OOO Compaction without dependency on in-order head Compaction #11847

Other actions

• Write documentation on how to enable out-of-order. (Done)
• Write a Prometheus blogpost announcing out-of-order as stable.
• Highlight this on the next release when it happens. (Done)

[roidelapluie]

Requires #11730

[Pushpendra100]

Hey @jesusvazquez , I am interested in doing this project as this is listed in LFX mentorship program. I have setup the repo and trying to understand the codebase. If you have any suggestion or information to share, please let me know.

[ArthurSens]

A good place to start might be reading the original Out-of-order proposal and understanding how it works :)

https://docs.google.com/document/d/1Kppm7qL9C-BJB1j6yb6-9ObG3AbdZnFUBYPNNWwDBYM/edit#heading=h.unv3m5m27vuc

[Atharva-Kanherkar]

Hi @ArthurSens!

Are there any pre-requisites for the application of LFX mentorship in this issue? (Other than an open mind and some existing skills :) )

[ArthurSens]

I'm not the mentor for this project, so I'm not the best person to ask that. I'd say that this project is somewhat complex, so understanding Prometheus internals might be a requirement.

But again, it would be better to ask the official mentors, as they might have different opinions and it's them who are going to make the selection :)

cc @jesusvazquez @bboreham

[Atharva-Kanherkar]

@ArthurSens Where can I contact them?

[jesusvazquez]

👋 @Atharva-Kanherkar a mentee has already been elected for the LFX project. Work is public at #prometheus-lfx-mentorship-out-of-order-stable in the CNCF slack! Although no more mentees will be included feel free to help or comment on things if you still have interest. Thanks!