query/sidecar: same store.limits flags on both components

[arnoldyahad]

Thanos and Prometheus version used:

Thanos 0.34.1
Prometheus v2.51.1

What happened:
We are trying to implement limits on querying to avoid thanos-querier reaching OOM.

We want to utilize these 2 flags:

--store.limits.request-samples
--store.limits.request-series

We see in the docs they both appear for the Sidecar and the querier:
https://thanos.io/tip/components/sidecar.md/#flags
https://thanos.io/tip/components/query.md/#flags

but when setting the flags on querier it doesn't block anything.
but still shows them in the UI as they are set.

only when setting them on the Sidecar it actually blocks.

What you expected to happen:
Flags to work when they set either in sidecar or querier.
Also - if both flags are set in these 2 components - which takes precedence?

How to reproduce it (as minimally and precisely as possible):
set up prometheus + thanos sidecar in one pod and another pod of thanos querier.

set these 2 flags with values other than 0 on the querier:

--store.limits.request-samples=100
--store.limits.request-series=5

set these 2 flags with different values on the sidecar.
try to query prometheus through thanos querier - and see that the values that are set in the querier dont really apply anything.

is this the desire behavior?

[tizki]

I'm having the same issue, tried to debug it locally and it seems that the query doesn't get to the part in the code that checks those limits.
it's either a bug or wrong documentation.

[MichaHoffmann]

You were right, those flags were just ignored during query evaluation since we didnt use the limited proxy store in the queryable that is passed to the promql engine! I opened #7679 to fix it.

[yeya24]

Given that #7679 has been merged, can we close this issue?

[arnoldyahad]

@yeya24 @MichaHoffmann thanks a lot for answering and sorry for the delay,
i would ask to close the issue if i had a release to test it but looking at #7679 - its not a part of any release

is there going to be a release soon where i can test it?