bench: add benchmarks for first_value, last_value

datafusion/functions-aggregate/Cargo.toml

@@ -79,3 +79,7 @@ name = "min_max_bytes"
 [[bench]]
 name = "approx_distinct"
 harness = false
+
+[[bench]]
+name = "first_last"
+harness = false

datafusion/functions-aggregate/benches/first_last.rs

@@ -0,0 +1,262 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+use std::hint::black_box;
+use std::sync::Arc;
+
+use arrow::array::{ArrayRef, BooleanArray};
+use arrow::compute::SortOptions;
+use arrow::datatypes::{DataType, Field, Int64Type, Schema};
+use arrow::util::bench_util::{create_boolean_array, create_primitive_array};
+
+use datafusion_expr::{
+    Accumulator, AggregateUDFImpl, EmitTo, GroupsAccumulator, function::AccumulatorArgs,
+};
+use datafusion_functions_aggregate::first_last::{FirstValue, LastValue};
+use datafusion_physical_expr::PhysicalSortExpr;
+use datafusion_physical_expr::expressions::col;
+
+use criterion::{Criterion, criterion_group, criterion_main};
+
+fn prepare_groups_accumulator(is_first: bool) -> Box<dyn GroupsAccumulator> {
+    let schema = Arc::new(Schema::new(vec![
+        Field::new("value", DataType::Int64, true),
+        Field::new("ord", DataType::Int64, true),
+    ]));
+
+    let order_expr = col("ord", &schema).unwrap();
+    let sort_expr = PhysicalSortExpr {
+        expr: order_expr,
+        options: SortOptions::default(),
+    };
+
+    let value_field: Arc<Field> = Field::new("value", DataType::Int64, true).into();
+    let accumulator_args = AccumulatorArgs {
+        return_field: Arc::clone(&value_field),
+        schema: &schema,
+        expr_fields: &[value_field],
+        ignore_nulls: false,
+        order_bys: std::slice::from_ref(&sort_expr),
+        is_reversed: false,
+        name: if is_first {
+            "FIRST_VALUE(value ORDER BY ord)"
+        } else {
+            "LAST_VALUE(value ORDER BY ord)"
+        },
+        is_distinct: false,
+        exprs: &[col("value", &schema).unwrap()],
+    };
+
+    if is_first {
+        FirstValue::new()
+            .create_groups_accumulator(accumulator_args)
+            .unwrap()
+    } else {
+        LastValue::new()
+            .create_groups_accumulator(accumulator_args)
+            .unwrap()
+    }
+}
+
+fn prepare_accumulator(is_first: bool) -> Box<dyn Accumulator> {
+    let schema = Arc::new(Schema::new(vec![
+        Field::new("value", DataType::Int64, true),
+        Field::new("ord", DataType::Int64, true),
+    ]));
+
+    let order_expr = col("ord", &schema).unwrap();
+    let sort_expr = PhysicalSortExpr {
+        expr: order_expr,
+        options: SortOptions::default(),
+    };
+
+    let value_field: Arc<Field> = Field::new("value", DataType::Int64, true).into();
+    let accumulator_args = AccumulatorArgs {
+        return_field: Arc::clone(&value_field),
+        schema: &schema,
+        expr_fields: &[value_field],
+        ignore_nulls: false,
+        order_bys: std::slice::from_ref(&sort_expr),
+        is_reversed: false,
+        name: if is_first {
+            "FIRST_VALUE(value ORDER BY ord)"
+        } else {
+            "LAST_VALUE(value ORDER BY ord)"
+        },
+        is_distinct: false,
+        exprs: &[col("value", &schema).unwrap()],
+    };
+
+    if is_first {
+        FirstValue::new().accumulator(accumulator_args).unwrap()
+    } else {
+        LastValue::new().accumulator(accumulator_args).unwrap()
+    }
+}
+
+#[expect(clippy::needless_pass_by_value)]
+fn convert_to_state_bench(
+    c: &mut Criterion,
+    is_first: bool,
+    name: &str,
+    values: ArrayRef,
+    opt_filter: Option<&BooleanArray>,
+) {
+    c.bench_function(name, |b| {
+        b.iter(|| {
+            let accumulator = prepare_groups_accumulator(is_first);
+            black_box(
+                accumulator
+                    .convert_to_state(std::slice::from_ref(&values), opt_filter)
+                    .unwrap(),
+            )
+        })
+    });
+}
+
+#[expect(clippy::needless_pass_by_value)]
+fn evaluate_accumulator_bench(
+    c: &mut Criterion,
+    is_first: bool,
+    name: &str,
+    values: ArrayRef,
+    ord: ArrayRef,
+) {
+    c.bench_function(name, |b| {
+        b.iter_batched(
+            || {
+                // setup, not timed
+                let mut accumulator = prepare_accumulator(is_first);
+                accumulator
+                    .update_batch(&[Arc::clone(&values), Arc::clone(&ord)])
+                    .unwrap();
+                accumulator
+            },
+            |mut accumulator| black_box(accumulator.evaluate().unwrap()),
+            criterion::BatchSize::SmallInput,
+        )
+    });
+}
+
+#[expect(clippy::needless_pass_by_value)]
+#[expect(clippy::too_many_arguments)]
+fn evaluate_bench(
+    c: &mut Criterion,
+    is_first: bool,
+    emit_to: EmitTo,
+    name: &str,
+    values: ArrayRef,
+    ord: ArrayRef,
+    opt_filter: Option<&BooleanArray>,
+    num_groups: usize,
+) {
+    let n = values.len();
+    let group_indices: Vec<usize> = (0..n).map(|i| i % num_groups).collect();
+
+    c.bench_function(name, |b| {
+        b.iter_batched(
+            || {
+                // setup, not timed
+                let mut accumulator = prepare_groups_accumulator(is_first);
+                accumulator
+                    .update_batch(
+                        &[Arc::clone(&values), Arc::clone(&ord)],
+                        &group_indices,
+                        opt_filter,
+                        num_groups,
+                    )
+                    .unwrap();
+                accumulator
+            },
+            |mut accumulator| black_box(accumulator.evaluate(emit_to).unwrap()),
+            criterion::BatchSize::SmallInput,
+        )
+    });
+}
+
+fn first_last_benchmark(c: &mut Criterion) {
+    const N: usize = 65536;
+    const NUM_GROUPS: usize = 1024;
+
+    assert_eq!(N % NUM_GROUPS, 0);
+
+    for is_first in [true, false] {
+        for pct in [0, 90] {
+            let fn_name = if is_first {
+                "first_value"
+            } else {
+                "last_value"
+            };
+
+            let null_density = (pct as f32) / 100.0;
+            let values = Arc::new(create_primitive_array::<Int64Type>(N, null_density))
+                as ArrayRef;
+            let ord = Arc::new(create_primitive_array::<Int64Type>(N, null_density))
+                as ArrayRef;
+
+            evaluate_accumulator_bench(
+                c,
+                is_first,
+                &format!("{fn_name} evaluate_accumulator_bench nulls={pct}%"),
+                values.clone(),
+                ord.clone(),
+            );
+
+            for with_filter in [false, true] {
+                let filter = create_boolean_array(N, 0.0, 0.5);
+                let opt_filter = if with_filter { Some(&filter) } else { None };
+
+                convert_to_state_bench(
+                    c,
+                    is_first,
+                    &format!(
+                        "{fn_name} convert_to_state nulls={pct}%, filter={with_filter}"
+                    ),
+                    values.clone(),
+                    opt_filter,
+                );
+                evaluate_bench(
+                    c,
+                    is_first,
+                    EmitTo::First(2),
+                    &format!(
+                        "{fn_name} evaluate_bench nulls={pct}%, filter={with_filter}, first(2)"
+                    ),
+                    values.clone(),
+                    ord.clone(),
+                    opt_filter,
+                    NUM_GROUPS,
+                );
+                evaluate_bench(
+                    c,
+                    is_first,
+                    EmitTo::All,
+                    &format!(
+                        "{fn_name} evaluate_bench nulls={pct}%, filter={with_filter}, all"
+                    ),
+                    values.clone(),
+                    ord.clone(),
+                    opt_filter,
+                    NUM_GROUPS,
+                );
+            }
+        }
+    }
+}
+
+criterion_group!(benches, first_last_benchmark);
+criterion_main!(benches);