harshmotw-db commented on code in PR #7944: URL: https://github.com/apache/arrow-rs/pull/7944#discussion_r2212320752
########## parquet-variant-compute/benches/variant_kernels.rs: ########## @@ -0,0 +1,237 @@ +// 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 arrow::array::{ArrayRef, StringArray}; +use arrow::util::test_util::seedable_rng; +use criterion::{criterion_group, criterion_main, Criterion}; +use parquet_variant::{Variant, VariantBuilder}; +use parquet_variant_compute::variant_get::{variant_get, GetOptions}; +use parquet_variant_compute::{batch_json_string_to_variant, VariantArray, VariantArrayBuilder}; +use rand::distr::Alphanumeric; +use rand::rngs::StdRng; +use rand::Rng; +use rand::SeedableRng; +use std::fmt::Write; +use std::sync::Arc; + +/// This function generates a vector of JSON strings, each representing a person +/// with random first name, last name, and age. +/// +/// Example: +/// ```json +/// { +/// "first" : random_string_of_1_to_20_characters, +/// "last" : random_string_of_1_to_20_characters, +/// "age": random_value_between_20_and_80, +/// } +/// ``` +fn small_repeated_json_structure(count: usize) -> impl Iterator<Item = String> { + let mut rng = seedable_rng(); + (0..count).map(move |_| { + let first: String = (0..rng.random_range(1..=20)) + .map(|_| rng.sample(Alphanumeric) as char) + .collect(); + let last: String = (0..rng.random_range(1..=20)) + .map(|_| rng.sample(Alphanumeric) as char) + .collect(); + let age: u8 = rng.random_range(20..=80); + format!("{{\"first\":\"{first}\",\"last\":\"{last}\",\"age\":{age}}}") + }) +} + +/// This function generates a vector of JSON strings which have many fields +/// and a random structure (including field names) +fn small_random_json_structure(count: usize) -> impl Iterator<Item = String> { + let mut generator = RandomJsonGenerator::new(); + (0..count).map(move |_| generator.next().to_string()) +} + +fn benchmark_batch_json_string_to_variant(c: &mut Criterion) { + let input_array = StringArray::from_iter_values(small_repeated_json_structure(8000)); + let array_ref: ArrayRef = Arc::new(input_array); + c.bench_function( + "batch_json_string_to_variant small_repeated_json 8k string", + |b| { + b.iter(|| { + let _ = batch_json_string_to_variant(&array_ref).unwrap(); + }); + }, + ); + + let input_array = StringArray::from_iter_values(small_random_json_structure(8000)); + let array_ref: ArrayRef = Arc::new(input_array); + c.bench_function( + "batch_json_string_to_variant small_random_json 8k string", + |b| { + b.iter(|| { + let _ = batch_json_string_to_variant(&array_ref).unwrap(); + }); + }, + ); +} + +fn create_primitive_variant(size: usize) -> VariantArray { + let mut rng = StdRng::seed_from_u64(42); + + let mut variant_builder = VariantArrayBuilder::new(1); + + for _ in 0..size { + let mut builder = VariantBuilder::new(); + builder.append_value(rng.random::<i64>()); + let (metadata, value) = builder.finish(); + variant_builder.append_variant(Variant::try_new(&metadata, &value).unwrap()); + } + + variant_builder.build() +} + +pub fn variant_get_bench(c: &mut Criterion) { + let variant_array = create_primitive_variant(8192); + let input: ArrayRef = Arc::new(variant_array); + + let options = GetOptions { + path: vec![].into(), + as_type: None, + cast_options: Default::default(), + }; + + c.bench_function("variant_get_primitive", |b| { + b.iter(|| variant_get(&input.clone(), options.clone())) + }); +} + +criterion_group!( + benches, + variant_get_bench, + benchmark_batch_json_string_to_variant +); +criterion_main!(benches); + +/// Creates JSON with random structure and fields. +/// +/// Each type is created in a random proportion, controlled by the +/// probabilities. The sum of all probabilities should be 1.0. +struct RandomJsonGenerator { + /// Random number generator + rng: StdRng, + /// the probability of generating a null value + null_probability: f64, + /// the probably of generating a string value + string_probability: f64, + /// the probably of generating a number value + number_probability: f64, + /// the probably of generating a boolean value + boolean_probability: f64, + /// the probably of generating an object value + object_probability: f64, + // probability of generating a JSON array is the remaining probability + /// The maximum depth of the generated JSON structure + max_depth: usize, + /// output buffer + output_buffer: String, +} + +impl RandomJsonGenerator { + fn new() -> Self { + let rng = seedable_rng(); + Self { + rng, + null_probability: 0.05, + string_probability: 0.25, + number_probability: 0.25, + boolean_probability: 0.10, + object_probability: 0.10, + max_depth: 5, + output_buffer: String::new(), + } + } + + fn next(&mut self) -> &str { + self.output_buffer.clear(); + self.append_random_json(0); + &self.output_buffer + } + + /// Appends a random JSON value to the output buffer. + fn append_random_json(&mut self, current_depth: usize) { + if current_depth >= self.max_depth { + write!(&mut self.output_buffer, "\"max_depth reached\"").unwrap(); + return; + } + // Generate a random number to determine the type + let random_value: f64 = self.rng.random(); + if random_value < self.null_probability { + write!(&mut self.output_buffer, "null").unwrap(); + } else if random_value < self.null_probability + self.string_probability { + // Generate a random string between 1 and 500 characters + let length = self.rng.random_range(1..=500); + let random_string: String = (0..length) + .map(|_| self.rng.sample(Alphanumeric) as char) + .collect(); + write!(&mut self.output_buffer, "\"{random_string}\"",).unwrap(); + } else if random_value + < self.null_probability + self.string_probability + self.number_probability + { + // Generate a random number + let random_number: f64 = self.rng.random_range(-1000.0..1000.0); + write!(&mut self.output_buffer, "{random_number}",).unwrap(); + } else if random_value + < self.null_probability + + self.string_probability + + self.number_probability + + self.boolean_probability + { + // Generate a random boolean + let random_boolean: bool = self.rng.random(); + write!(&mut self.output_buffer, "{random_boolean}",).unwrap(); + } else if random_value + < self.null_probability + + self.string_probability + + self.number_probability + + self.boolean_probability + + self.object_probability + { + // Generate a random object + let num_fields = self.rng.random_range(1..=10); + + write!(&mut self.output_buffer, "{{").unwrap(); + for i in 0..num_fields { + let key_length = self.rng.random_range(1..=20); + let key: String = (0..key_length) + .map(|_| self.rng.sample(Alphanumeric) as char) + .collect(); + write!(&mut self.output_buffer, "\"{key}\":").unwrap(); + self.append_random_json(current_depth + 1); + if i < num_fields - 1 { + write!(&mut self.output_buffer, ",").unwrap(); + } + } + write!(&mut self.output_buffer, "}}").unwrap(); + } else { + // Generate a random array + let length = self.rng.random_range(1..=10); Review Comment: Instead of having these as hard-coded constants, is there merit to having `maxArraySize` and `maxObjectSize` be parameters of RandomJsonGenerator? Similar parameters could also be added for string lengths if we're okay with crowding the struct. **Edit:** Having a `maxNestedWidth` which controls both `maxArraySize` and `maxObjectSize` sounds like a good idea. -- 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: github-unsubscr...@arrow.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org
