pitrou commented on code in PR #43661: URL: https://github.com/apache/arrow/pull/43661#discussion_r2451523468
########## cpp/src/arrow/dataset/parquet_scan_benchmark.cc: ########## @@ -0,0 +1,96 @@ +// 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. + +#include "arrow/testing/gtest_util.h" +#include "benchmark/benchmark.h" + +#include "arrow/api.h" +#include "arrow/compute/initialize.h" +#include "arrow/dataset/dataset.h" +#include "arrow/dataset/file_parquet.h" +#include "arrow/dataset/scanner.h" +#include "arrow/io/memory.h" +#include "parquet/arrow/writer.h" + +namespace arrow { +namespace dataset { + +using parquet::arrow::WriteTable; + +Result<std::shared_ptr<Buffer>> WriteStringColParquetBuffer(int64_t nrows) { + auto schema = arrow::schema({arrow::field("my_string_col", arrow::utf8())}); + + arrow::StringBuilder builder; + for (int64_t i = 0; i < nrows; i++) { + ARROW_RETURN_NOT_OK(builder.Append("row_" + std::to_string(i))); + } + std::shared_ptr<arrow::Array> arr; + ARROW_RETURN_NOT_OK(builder.Finish(&arr)); + auto table = arrow::Table::Make(schema, {arr}); + + ARROW_ASSIGN_OR_RAISE(auto sink, arrow::io::BufferOutputStream::Create()); + ARROW_RETURN_NOT_OK(WriteTable(*table, arrow::default_memory_pool(), sink)); + return sink->Finish(); +} + +static void ParquetScanToTableCastStrings(benchmark::State& state) { + // GH-43660: Scan parquet data including a String column using a dataset object with + // LargeString in schema. + size_t num_batches = state.range(0); + size_t batch_size = state.range(1); + size_t nrows = num_batches * batch_size; + auto format = std::make_shared<ParquetFileFormat>(); + + // Create a buffer with a single String column and wrap with FileFragment + ASSERT_OK_AND_ASSIGN(std::shared_ptr<Buffer> buffer, + WriteStringColParquetBuffer(nrows)); + auto buffer_reader = std::make_shared<arrow::io::BufferReader>(buffer); + FileSource source(buffer_reader, buffer->size()); + ASSERT_OK_AND_ASSIGN(auto fragment, format->MakeFragment(source)); + std::vector<std::shared_ptr<FileFragment>> fragments{fragment}; + + // Create a dataset from FileFragment and set schema to LargeString (require casting). + auto schema = arrow::schema({field("my_string_col", arrow::large_utf8())}); + ASSERT_OK_AND_ASSIGN(auto dataset, FileSystemDataset::Make( + schema, compute::literal(true), format, + /*filesystem=*/nullptr, std::move(fragments))); + + ASSERT_OK_AND_ASSIGN(auto builder, dataset->NewScan()); + ASSERT_OK(builder->BatchSize(batch_size)); + ASSERT_OK_AND_ASSIGN(auto scanner, builder->Finish()); + + for (auto _ : state) { + ASSERT_OK_AND_ASSIGN(auto table, scanner->ToTable()); + benchmark::DoNotOptimize(table); + } + + state.SetItemsProcessed(state.iterations() * nrows); +} + +static void ParquetScanBenchmark_Customize(benchmark::internal::Benchmark* b) { + for (const int32_t num_batches : {1000}) { + for (const int batch_size : {10, 100, 1000}) { Review Comment: Those batch sizes are much too small for good performance, so I'm not sure why they're being benchmarked. You could instead try `{1000, 10000, 100000}`. -- 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]
