chore: create benches small ints for count_distinct (#21521)

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- Closes #.

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Author: coderfender

datafusion/functions-aggregate/Cargo.toml

@@ -83,3 +83,7 @@ harness = false
 [[bench]]
 name = "first_last"
 harness = false
+
+[[bench]]
+name = "count_distinct"
+harness = false

datafusion/functions-aggregate/benches/approx_distinct.rs

@@ -17,7 +17,10 @@
 
 use std::sync::Arc;
 
-use arrow::array::{ArrayRef, Int64Array, StringArray, StringViewArray};
+use arrow::array::{
+    ArrayRef, Int8Array, Int16Array, Int64Array, StringArray, StringViewArray,
+    UInt8Array, UInt16Array,
+};
 use arrow::datatypes::{DataType, Field, Schema};
 use criterion::{Criterion, criterion_group, criterion_main};
 use datafusion_expr::function::AccumulatorArgs;
@@ -56,6 +59,38 @@ fn create_i64_array(n_distinct: usize) -> Int64Array {
         .collect()
 }
 
+fn create_u8_array(n_distinct: usize) -> UInt8Array {
+    let mut rng = StdRng::seed_from_u64(42);
+    let max_val = n_distinct.min(256) as u8;
+    (0..BATCH_SIZE)
+        .map(|_| Some(rng.random_range(0..max_val)))
+        .collect()
+}
+
+fn create_i8_array(n_distinct: usize) -> Int8Array {
+    let mut rng = StdRng::seed_from_u64(42);
+    let max_val = (n_distinct.min(256) / 2) as i8;
+    (0..BATCH_SIZE)
+        .map(|_| Some(rng.random_range(-max_val..max_val)))
+        .collect()
+}
+
+fn create_u16_array(n_distinct: usize) -> UInt16Array {
+    let mut rng = StdRng::seed_from_u64(42);
+    let max_val = n_distinct.min(65536) as u16;
+    (0..BATCH_SIZE)
+        .map(|_| Some(rng.random_range(0..max_val)))
+        .collect()
+}
+
+fn create_i16_array(n_distinct: usize) -> Int16Array {
+    let mut rng = StdRng::seed_from_u64(42);
+    let max_val = (n_distinct.min(65536) / 2) as i16;
+    (0..BATCH_SIZE)
+        .map(|_| Some(rng.random_range(-max_val..max_val)))
+        .collect()
+}
+
 /// Creates a pool of `n_distinct` random strings of the given length.
 fn create_string_pool(n_distinct: usize, string_length: usize) -> Vec<String> {
     let mut rng = StdRng::seed_from_u64(42);
@@ -133,6 +168,52 @@ fn approx_distinct_benchmark(c: &mut Criterion) {
             );
         }
     }
+
+    // Small integer types
+
+    // UInt8
+    let values = Arc::new(create_u8_array(200)) as ArrayRef;
+    c.bench_function("approx_distinct u8 bitmap", |b| {
+        b.iter(|| {
+            let mut accumulator = prepare_accumulator(DataType::UInt8);
+            accumulator
+                .update_batch(std::slice::from_ref(&values))
+                .unwrap()
+        })
+    });
+
+    // Int8
+    let values = Arc::new(create_i8_array(200)) as ArrayRef;
+    c.bench_function("approx_distinct i8 bitmap", |b| {
+        b.iter(|| {
+            let mut accumulator = prepare_accumulator(DataType::Int8);
+            accumulator
+                .update_batch(std::slice::from_ref(&values))
+                .unwrap()
+        })
+    });
+
+    // UInt16
+    let values = Arc::new(create_u16_array(50000)) as ArrayRef;
+    c.bench_function("approx_distinct u16 bitmap", |b| {
+        b.iter(|| {
+            let mut accumulator = prepare_accumulator(DataType::UInt16);
+            accumulator
+                .update_batch(std::slice::from_ref(&values))
+                .unwrap()
+        })
+    });
+
+    // Int16
+    let values = Arc::new(create_i16_array(50000)) as ArrayRef;
+    c.bench_function("approx_distinct i16 bitmap", |b| {
+        b.iter(|| {
+            let mut accumulator = prepare_accumulator(DataType::Int16);
+            accumulator
+                .update_batch(std::slice::from_ref(&values))
+                .unwrap()
+        })
+    });
 }
 
 criterion_group!(benches, approx_distinct_benchmark);

datafusion/functions-aggregate/benches/count_distinct.rs

@@ -0,0 +1,154 @@
+// 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::sync::Arc;
+
+use arrow::array::{
+    ArrayRef, Int8Array, Int16Array, Int64Array, UInt8Array, UInt16Array,
+};
+use arrow::datatypes::{DataType, Field, Schema};
+use criterion::{Criterion, criterion_group, criterion_main};
+use datafusion_expr::function::AccumulatorArgs;
+use datafusion_expr::{Accumulator, AggregateUDFImpl};
+use datafusion_functions_aggregate::count::Count;
+use datafusion_physical_expr::expressions::col;
+use rand::rngs::StdRng;
+use rand::{Rng, SeedableRng};
+
+const BATCH_SIZE: usize = 8192;
+
+fn prepare_accumulator(data_type: DataType) -> Box<dyn Accumulator> {
+    let schema = Arc::new(Schema::new(vec![Field::new("f", data_type, true)]));
+    let expr = col("f", &schema).unwrap();
+    let accumulator_args = AccumulatorArgs {
+        return_field: Field::new("f", DataType::Int64, true).into(),
+        schema: &schema,
+        expr_fields: &[expr.return_field(&schema).unwrap()],
+        ignore_nulls: false,
+        order_bys: &[],
+        is_reversed: false,
+        name: "count(distinct f)",
+        is_distinct: true,
+        exprs: &[expr],
+    };
+    Count::new().accumulator(accumulator_args).unwrap()
+}
+
+fn create_i64_array(n_distinct: usize) -> Int64Array {
+    let mut rng = StdRng::seed_from_u64(42);
+    (0..BATCH_SIZE)
+        .map(|_| Some(rng.random_range(0..n_distinct as i64)))
+        .collect()
+}
+
+fn create_u8_array(n_distinct: usize) -> UInt8Array {
+    let mut rng = StdRng::seed_from_u64(42);
+    let max_val = n_distinct.min(256) as u8;
+    (0..BATCH_SIZE)
+        .map(|_| Some(rng.random_range(0..max_val)))
+        .collect()
+}
+
+fn create_i8_array(n_distinct: usize) -> Int8Array {
+    let mut rng = StdRng::seed_from_u64(42);
+    let max_val = (n_distinct.min(256) / 2) as i8;
+    (0..BATCH_SIZE)
+        .map(|_| Some(rng.random_range(-max_val..max_val)))
+        .collect()
+}
+
+fn create_u16_array(n_distinct: usize) -> UInt16Array {
+    let mut rng = StdRng::seed_from_u64(42);
+    let max_val = n_distinct.min(65536) as u16;
+    (0..BATCH_SIZE)
+        .map(|_| Some(rng.random_range(0..max_val)))
+        .collect()
+}
+
+fn create_i16_array(n_distinct: usize) -> Int16Array {
+    let mut rng = StdRng::seed_from_u64(42);
+    let max_val = (n_distinct.min(65536) / 2) as i16;
+    (0..BATCH_SIZE)
+        .map(|_| Some(rng.random_range(-max_val..max_val)))
+        .collect()
+}
+
+fn count_distinct_benchmark(c: &mut Criterion) {
+    for pct in [80, 99] {
+        let n_distinct = BATCH_SIZE * pct / 100;
+
+        // Int64
+        let values = Arc::new(create_i64_array(n_distinct)) as ArrayRef;
+        c.bench_function(&format!("count_distinct i64 {pct}% distinct"), |b| {
+            b.iter(|| {
+                let mut accumulator = prepare_accumulator(DataType::Int64);
+                accumulator
+                    .update_batch(std::slice::from_ref(&values))
+                    .unwrap()
+            })
+        });
+    }
+
+    // Small integer types
+
+    // UInt8
+    let values = Arc::new(create_u8_array(200)) as ArrayRef;
+    c.bench_function("count_distinct u8 bitmap", |b| {
+        b.iter(|| {
+            let mut accumulator = prepare_accumulator(DataType::UInt8);
+            accumulator
+                .update_batch(std::slice::from_ref(&values))
+                .unwrap()
+        })
+    });
+
+    // Int8
+    let values = Arc::new(create_i8_array(200)) as ArrayRef;
+    c.bench_function("count_distinct i8 bitmap", |b| {
+        b.iter(|| {
+            let mut accumulator = prepare_accumulator(DataType::Int8);
+            accumulator
+                .update_batch(std::slice::from_ref(&values))
+                .unwrap()
+        })
+    });
+
+    // UInt16
+    let values = Arc::new(create_u16_array(50000)) as ArrayRef;
+    c.bench_function("count_distinct u16 bitmap", |b| {
+        b.iter(|| {
+            let mut accumulator = prepare_accumulator(DataType::UInt16);
+            accumulator
+                .update_batch(std::slice::from_ref(&values))
+                .unwrap()
+        })
+    });
+
+    // Int16
+    let values = Arc::new(create_i16_array(50000)) as ArrayRef;
+    c.bench_function("count_distinct i16 bitmap", |b| {
+        b.iter(|| {
+            let mut accumulator = prepare_accumulator(DataType::Int16);
+            accumulator
+                .update_batch(std::slice::from_ref(&values))
+                .unwrap()
+        })
+    });
+}
+
+criterion_group!(benches, count_distinct_benchmark);
+criterion_main!(benches);