Could not publish attestation message due to `NoPeersSubscribedToTopic`

[jimmygchen]

Description

Seeing this warning a lot on some Holesky nodes with 200 peers:

Oct 02 02:05:43.029 WARN  Could not publish message                     error: NoPeersSubscribedToTopic, kind: beacon_attestation_5

Version

v8.0.0-rc.0

Present Behaviour

The beacon node doesn't have sufficient peers on the attestation subnets its publishing to. This is likely caused by a recent change (#7915), which prioritises uniform distribution across data column subnets instead of attestation subnets from the Fulu fork.

Expected Behaviour

The beacon node should have sufficient peers on its required attestation subnets most of the time and the frequency of this warning should be low.

[jimmygchen]

oh looks like my previous message wasn't sent and i've lost it.

The log showing why we're not getting those attestation subnet peers:

	Oct 08 22:59:27.757 WARN  Not enough time for a discovery search        subnet_id: Attestation(SubnetId(14))

It looks like we're sending the discovery request too late and the request is ignored. The fact that 99% of these warnings are on holesky hints that it may be related to the other performance issues we're seeing on holesky (delayed sync message processing etc)

[jimmygchen]

Not seeing this much on Hoodi / Sepolia, given that this is just a symptom from performance issues - I'm going to close this now.

The optimisation in #8176 may improve holesky performance.