Reviewed by Aditya Kumar Ā· 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. Monitor Spark jobs: (1) Spark UIāstages, tasks, storage; (2) Spark History Server for completed; (3) Logsādriver, executor; (4)...
Why it matters: At scale, design choices directly impact reliability, latency, and cost. Wrong decisions compound across jobs and teams.
Monitor Spark jobs: (1) Spark UIāstages, tasks, storage; (2) Spark History Server for completed; (3) Logsādriver, executor; (4) MetricsāGanglia, Prometheus. Best practice: enable event logging; set up history server; monitor duration and failures; use Spark listener for custom metrics.
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 history server. Pro-Move: 'Event log S3; History Server; dashboards.'
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