Unbounded Redis memory growth from pipeline execution retention

Redis memory usage grows unbounded because Spinnaker's Orca orchestration engine stores all pipeline executions forever by default. Without cleanup enabled, historical execution data accumulates indefinitely, eventually exhausting Redis memory and risking OOM conditions.

Enable old pipeline cleanup in ~/.hal/$DEPLOYMENT/profiles/orca-local.yml by setting pollers.oldPipelineCleanup.enabled: true. Configure retention thresholds: thresholdDays (default 30) controls deletion age, minimumPipelineExecutions (default 5) ensures recent executions are preserved, and intervalMs (default 3600000) sets cleanup frequency. Set tasks.controller.daysOfExecutionHistory to limit task execution retention.