Cut 0.23.0-rc.1 and cherry picked 3 critical commits from main.

[bwplotka]

Things I cherry picked:

• Query: Fix (*exemplarsStream).receive/(*metricMetadataStream).receive/(*targetsStreamStream).receive infinite loop when target response Unimplemented error (Exemplar: Can not set partial response. #4676) (Query: Fix (*Stream).receive infinite loop when target response Unimplemented error (#4676) #4681)
• pgrade Prometheus dependency version to v2.30.0 (upgrade Prometheus dependency version to v2.30.0 #4669)
• Sidecar: Fix process external label on promethues v2.28+ use units.Bytes config type (Sidecar: Fix process external label on promethues v2.28+ use units.Bytes config type #4657)

Also, let's make sure we merge this PR without squash.

Let's not try to add too many things in this release, we already waited long.

[onprem]

LGTM!

[hanjm]

Hi @yeya24 @bwplotka , #4680 add exemplar.partial-response flag also critical for compatible with old version sidecar. If there is a old version sidecar in sidecar cluster, thanos-query query exemplar will response fail.

[bwplotka]

@hanjm It's just a flag addition, so I did not have enough context to merge this one... We can't postpone release forever, can we release without it, since mitigation is known and exemplars are not core functionality?

[hanjm]

@hanjm It's just a flag addition, so I did not have enough context to merge this one... We can't postpone release forever, can we release without it, since mitigation is known and exemplars are not core functionality?

@bwplotka more context is: if without this flag. the exemplar-partial-response is always false. exemplar will response fail if many sidecar has one old version.

thanos/pkg/api/query/v1.go

Line 802 in ef03a32

if enablePartialResponse {

i just upgrade from 0.22 to 0.23.0 and the useful exemplar api break，then i fixed :) ，since exemplar is not core function it will be ok to release. thanks.

[bwplotka]

Yes, especially for power users like you and @yeya24 using main is the best choice (we do that too 🤗 )

[John-Lin]

Hi, team

I'm facing this errors after upgrade to v0.23.0 however I didn't use exemplar feature. As far as I know, it should not show error like this (I have no idea how to reproduce. I guess grafana enable exemplar feature by default cause this error)

level=error ts=2021-10-01T01:48:19.727416223Z caller=proxy.go:146 err="receiving exemplars from exemplars client &{0xc0162da000}: rpc error: code = Canceled desc = context canceled"
level=error ts=2021-10-01T01:48:23.383270697Z caller=proxy.go:146 err="fetching exemplars from exemplars client &{0xc0162da000}: rpc error: code = Canceled desc = context canceled"
level=error ts=2021-10-01T01:48:23.525155169Z caller=proxy.go:146 err="receiving exemplars from exemplars client &{0xc0000a4700}: rpc error: code = Canceled desc = context canceled"
level=error ts=2021-10-01T01:48:25.387262601Z caller=proxy.go:146 err="fetching exemplars from exemplars client &{0xc0162da000}: rpc error: code = Canceled desc = context canceled"

then I found these PRs #4680, #4681 might related. my question is will #4680, #4681 be merged in next release?
it seems like those PRs could fix this issue.