Replaced 'loki.source.kubernetes' with 'loki.source.file' in alloy DS
config. discovery.relabel.pod_logs already sets __path__ to the kubelet
log path (/var/log/pods/*<uid>/<container>/*.log) and varlog host-mount
was already present, so this is a one-line swap.
Why: apiserver was burning ~700m sustained on 'CONNECT pods/log' streams
(13 req/s, ~2200 sec/s of long-lived TCP connections). Streaming pod
logs through the apiserver instead of tailing kubelet's log files was
the dominant residual cost after the recent Loki/Alloy onboarding.
Measured before/after:
- Alloy DS: ~620m total (5 x ~125m) -> ~92m total (5 x ~18m)
- kube-apiserver: peak 1959m midnight burst, settled 632m
(Stuck-pod recovery: alloy-7zg7t on k8s-master needed --force delete
during rollout — FailedKillPod 'unable to signal init: permission denied'
on runc, transient runtime issue, unrelated to this change.)
5bc98851b9