Enum AggregateChoice 

pub enum AggregateChoice {
    Measured,
    ArrowMetal,
    DataFusion,
}

Who runs an aggregate the rule replaced.

The rule sees the input’s row count at plan time but not its group count, and the same aggregate SQL is faster on ArrowMetal at some group counts and slower at others. So a replaced aggregate is decided when it runs: MetalExec collects its input, and under Measured it estimates the group count from a sample of the key columns on the CPU and looks the shape up in the measured table (src/agg_table.rs). It runs on ArrowMetal only where the sweep measured it ahead; otherwise it hands the node back to DataFusion’s own operators over the same batches.

Variants

Measured

Estimate the group count and look it up in the measured table (the default). At plan time the rule replaces an aggregate only when the table takes its shape at some group count at the input’s exact row count.

ArrowMetal

Always run a replaced aggregate on ArrowMetal (the benchmark’s crossover sweep, tests).

DataFusion

Always hand a replaced aggregate back to DataFusion (measures the hand-back itself, tests).

Trait Implementations

impl Clone for AggregateChoice

fn clone(&self) -> Self

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Copy for AggregateChoice

impl Debug for AggregateChoice

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for AggregateChoice

fn default() -> Self

Returns the “default value” for a type.

impl Eq for AggregateChoice

impl PartialEq for AggregateChoice

fn eq(&self, other: &Self) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl StructuralPartialEq for AggregateChoice