fix: prevent unnecessary rolling restarts during node draining #1092
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When nodes are drained during K8S or OS upgrades, pods get deleted and recreated, but the StatefulSet revision doesn't change. The existing logic incorrectly triggered rolling restarts in these scenarios, causing all pods with lower ordinal numbers to be terminated simultaneously. This change adds revision comparison checks to prevent rolling restarts when StatefulSet current and update revisions match, indicating no actual spec changes occurred. Rolling restarts now only happen when there are legitimate configuration updates requiring pod recreation. Changes: - Add revision match checks in RollingRestartReconciler.Reconcile() - Enhance WorkingPodForRollingRestart() to skip when revisions match - Add debug logging to indicate when rolling restarts are skipped Fixes issues during node upgrades and other node draining scenarios where pods are recreated without spec changes. Signed-off-by: Itamar Syn-Hershko <[email protected]>
synhershko
requested review from
idanl21,
swoehrl-mw,
prudhvigodithi,
jochenkressin,
pchmielnik and
salyh
as code owners
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When nodes are drained during K8S or OS upgrades, pods get deleted and recreated, but the StatefulSet revision doesn't change. The existing logic incorrectly triggered rolling restarts in these scenarios, causing all pods with lower ordinal numbers to be terminated simultaneously.
This change adds revision comparison checks to prevent rolling restarts when StatefulSet current and update revisions match, indicating no actual spec changes occurred. Rolling restarts now only happen when there are legitimate configuration updates requiring pod recreation.
Changes:
Fixes issues during node upgrades and other node draining scenarios where pods are recreated without spec changes. Fixes #312.
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