The mirror reconcile path issued one direct apiserver GET per target
namespace on every pass. With N sources and M target namespaces each
resync produced N*M GET requests. On a 65-namespace cluster this
generated 63 GET/s and overloaded one control-plane node.
Changes:
- reconcileMirror now trusts the informer cache. Content drift is
detected via the source hash annotation. A stale resourceVersion
makes Update return a conflict, which requeues the source.
- The verify-source-freshness flag now defaults to false. The Helm
chart passes the value explicitly, so the chart default of false
matches the binary behaviour.
- Reconcile performs one namespace LIST per pass. Target resolution
and orphan cleanup share the result.
- Add load regression tests that count direct API reads in the
reconcile hot path.
exclude="true" opts a resource out of mirroring and tears down its existing mirrors; paused="true" freezes mirrors in place (no updates, no cleanup). Both respected by the source and namespace reconcilers. Also dedup target-namespace resolution via delegation, remove 8 unused annotation constants and their misleading godoc, and silence gosec G101 false positives on base64 test fixtures.
All registration goes through SetupWithManagerForResourceType (eager and
lazy paths in main.go); the legacy single-resource SetupWithManager and
its corev1 import were dead code that misled readers about how the
controller wires up.
C2: updateLastSyncStatus wrote the sync-status annotation on every
successful reconcile. Because the source's watch predicate is the
'enabled' label (server-side filter), that Update fires a watch event
that re-enters Reconcile. With reconciled/error counts varying across
cycles, the value differs each time, so the API server bumps RV and
the loop never quiesces. Now skips the Update when the value matches
the existing annotation.
C3: NamespaceReconciler's happy-path returned RequeueAfter=3s
unconditionally. Every namespace in the cluster re-reconciled every
3 seconds forever, generating constant List calls per source kind.
Now returns ctrl.Result{}; cache-staleness windows are handled by
the manager's resync period and source freshness verification.
C1: deleteAllMirrors used to issue a blind Delete on every namespace
matching the source name+GVK, which would destroy unrelated resources
(e.g. a 'default' SA, 'ca-bundle' ConfigMap) sharing the source name.
Now reads each candidate, verifies managed-by label and source-reference
annotation, and only deletes confirmed mirrors.
M1: BlacklistedSecretTypes was declared but never enforced. Enabling
mirroring on a service-account-token / bootstrap-token / helm release
Secret would mirror credentials cluster-wide. Now refused at Reconcile.
M3: deleteAllMirrors swallowed per-namespace errors and returned nil,
so callers removed the finalizer even on partial failure (orphans).
Errors are now joined and returned.
lukaszraczylo
