kosiew commented on code in PR #24800: URL: https://github.com/apache/datafusion/pull/24800#discussion_r3912836586
########## datafusion/physical-expr/benches/equivalence_properties.rs: ########## @@ -0,0 +1,150 @@ +// 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. + +//! Benchmarks for the ordering satisfaction checks on [`EquivalenceProperties`]. +//! +//! These are called repeatedly during physical optimization (sort removal, +//! `EnforceSorting`, `EnforceDistribution`, and the requirement checks for +//! windows, joins and aggregates), so their cost shows up directly in planning +//! time. +//! +//! The benchmarks are parameterized by the number of equivalence classes, since +//! that -- not the schema width, which is behind an `Arc` -- is what these +//! checks carry around. + +use std::sync::Arc; + +use arrow::compute::SortOptions; +use arrow::datatypes::{DataType, Field, Schema, SchemaRef}; +use criterion::{BenchmarkId, Criterion, criterion_group, criterion_main}; +use datafusion_physical_expr::expressions::Column; +use datafusion_physical_expr::{ + EquivalenceProperties, LexOrdering, PhysicalExpr, PhysicalSortExpr, + PhysicalSortRequirement, +}; + +fn schema(n_cols: usize) -> SchemaRef { + Arc::new(Schema::new( + (0..n_cols) + .map(|i| Field::new(format!("c{i}"), DataType::Int32, true)) + .collect::<Vec<_>>(), + )) +} + +fn col(i: usize) -> Arc<dyn PhysicalExpr> { + Arc::new(Column::new(&format!("c{i}"), i)) +} + +fn asc(i: usize) -> PhysicalSortExpr { + PhysicalSortExpr::new(col(i), SortOptions::default()) +} + +/// Properties with three equivalent orderings and `n_classes` equivalence +/// classes, i.e. roughly what a scan feeding a join and a window function looks +/// like. Columns `c0..c7` carry the orderings; the equivalence classes are built +/// from the columns above them. +fn properties(n_classes: usize) -> EquivalenceProperties { + let schema = schema(8 + 2 * n_classes); + let mut props = EquivalenceProperties::new(schema); + props.add_orderings([ + vec![asc(0), asc(1), asc(2), asc(3)], + vec![asc(4), asc(5)], + vec![asc(6)], + ]); + for i in 0..n_classes { + props + .add_equal_conditions(col(8 + 2 * i), col(9 + 2 * i)) + .unwrap(); + } + props +} + +fn bench_ordering_satisfaction(c: &mut Criterion) { + let mut group = c.benchmark_group("equivalence_properties"); + + for n_classes in [2, 8, 32] { + let props = properties(n_classes); + + // A single sort key: the most common shape by far. + group.bench_with_input( Review Comment: Nice to have benchmark coverage for this. One thought: if the goal is to isolate the cost of the satisfaction checks themselves, could we pre-build the ordering/requirement inputs and use `iter_batched` so the per-iteration setup stays outside the timed routine? Right now the closures also create `Column`s and `PhysicalSortExpr`s, and the prefix benchmark builds the `LexOrdering`, so those costs are included in the measurements. If the intention is to measure the end-to-end caller cost instead, keeping the setup here makes sense, but it would be helpful to document that scope. We would still want any cloning that is part of the operation under test to remain inside the timed iteration. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected] --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
