Reviewed by Aditya Kumar Β· Last reviewed 2026-03-25
**Why it matters**: At scale, design choices directly impact reliability, latency, and cost. Wrong decisions compound across jobs and teams. Production Spark monitoring: Spark UI/History; application logs; metrics (executor failures, GC); alerting on failures and SLA. Debug:...
Why it matters: At scale, design choices directly impact reliability, latency, and cost. Wrong decisions compound across jobs and teams.
Production Spark monitoring: Spark UI/History; application logs; metrics (executor failures, GC); alerting on failures and SLA. Debug: check failed task logs; identify skew; validate data. Best practice: centralized logging; structured logs; dashboards; runbooks for common failures; trace job lineage.
Scalability trade-offs: Partition/parallelism limits; single points of failure; horizontal vs vertical scaling. Cost implications: Sizing, spot vs reserved, optimization ROI.
Red Flag: No runbooks. Pro-Move: 'Centralized logs; runbooks; trace lineage.'
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