What problem does it solve?
This Skill helps you pinpoint why a Trino query is slow by interpreting EXPLAIN and EXPLAIN ANALYZE output, including distributed fragments, exchanges, skew, and operator-level bottlenecks.
Core Features & Use Cases
- Plan-type driven diagnosis: Read DISTRIBUTED, LOGICAL, IO, and VALIDATE views to confirm what the engine decided to do.
- Exchange and fragment analysis: Identify RemoteExchange patterns and fragment types (SINGLE/HASH/ROUND_ROBIN/BROADCAST/SOURCE) to reduce shuffle and network cost.
- Runtime metric interpretation: Detect skew using input row variance, spot spill and blocked-time issues, and compare estimated vs actual rows to catch stale stats and misplanning.
- Common slow-plan anti-patterns: Find missing partition pruning, predicate pushdown failures, cross joins, accidental extra repartitioning, and small-file split explosions.
Quick Start
Ask the agent to run EXPLAIN ANALYZE for your query and review the distributed fragments, RemoteExchange count, skew signals (input avg vs std.dev), and estimated-versus-actual row disparities to recommend the most likely fix.