[loki-distributed] Add index-gateway container lifecycle

[froblesmartin]

We want to be able to set a postStart lifecycle in the index-gateways.

The reason for it is that, with a few queries, the index-gateway pods run out of memory, and on top of setting a timeout for the queries (query_timeout), we also want to clean up the tsdb-cache folder on restarts of the pods.

Docs about this:

• https://kubernetes.io/docs/concepts/workloads/pods/pod-lifecycle/
• https://kubernetes.io/docs/reference/generated/kubernetes-api/v1.33/#lifecycle-v1-core

The same thing was done for the ingester at #2527

[froblesmartin]

@Sheikh-Abubaker @jkroepke I think the automatic reviewers assigned to the PRs are not active lately. May you review this small PR?

[jkroepke]

I highly recommend migrate to the official loki helm chart. It doesnt get any updates any more, including app updates.

[froblesmartin]

I highly recommend migrate to the official loki helm chart. It doesnt get any updates any more, including app updates.

Is it this one https://github.com/grafana/loki/tree/main/production/helm/loki?

[jkroepke]

Yes!

[froblesmartin]

Yes!

Cool! I will check to migrate to it. In the meantime, could this PR get reviewed?

[froblesmartin]

@jkroepke I was checking the loki Helm charts, and I see a bit of a mixed info there. Should I open a PR adding a note to all of them mentioning that they are not maintained anymore and to switch to the new one?

For example:

• loki: it clearly states to use the new one, it is even empty
• loki-simple-scalable: same as the previous
• loki-stack: it says it is maintained by the community, is this true? or like all the other should not be used anymore?
• loki-canary: nothing is mentioned but it is not maintained either.
• loki-distributed: same as the canary

[jkroepke]

@Jayclifford345 maybe you can give an better overview here.

Generally, there is now an offical Loki Helm Chart, maintained by the Loki Team at https://github.com/grafana/loki

This repository grafana/helm-charts is purely community driven. All charts here are mainly maintained by the community. Each chart have distinct maintainers.

The conclusion is that the helm charts are maintained by inactive community members. Since everything is community driven here, there is no official commitment, including an official statement about the maintainer status.

In reality, now that there is an official Loki chart, the community efforts in context of the mentioned Loki charts might stop completely.

At the moment, some selected community member now helps the Loki team to maintain the chart.

For record, this is just my point of view, as community maintainer for the Grafana Helm Chart here.