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Metrics

DataFusion operators expose runtime metrics so you can understand where time is spent and how much data flows through the pipeline. See more in EXPLAIN ANALYZE.

Common Metrics

BaselineMetrics

BaselineMetrics are available in most physical operators to capture common measurements.

Metric	Description
elapsed_compute	CPU time the operator actively spends processing work.
output_rows	Total number of rows the operator produces.
output_bytes	Memory usage of all output batches. Note: This value may be overestimated. If multiple output RecordBatch instances share underlying memory buffers, their sizes will be counted multiple times.
output_batches	Total number of output batches the operator produces.

Operator-specific Metrics

FilterExec

Metric	Description
selectivity	Selectivity of the filter, calculated as output_rows / input_rows

TODO

Add metrics for the remaining operators