kszucs commented on code in PR #45360: URL: https://github.com/apache/arrow/pull/45360#discussion_r1988119205
########## cpp/src/parquet/chunker_internal.cc: ########## @@ -0,0 +1,250 @@ +// 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 "parquet/chunker_internal.h" + +#include <cmath> +#include <string> +#include <vector> +#include "arrow/array.h" +#include "arrow/util/logging.h" +#include "parquet/chunker_internal_hashtable.h" +#include "parquet/exception.h" +#include "parquet/level_conversion.h" + +namespace parquet::internal { + +// create a fake null array class with a GetView method returning 0 always +class FakeNullArray { + public: + uint8_t GetView(int64_t i) const { return 0; } + + std::shared_ptr<::arrow::DataType> type() const { return ::arrow::null(); } + + int64_t null_count() const { return 0; } +}; + +static uint64_t GetMask(uint64_t min_size, uint64_t max_size, uint8_t norm_factor) { + // we aim for gaussian-like distribution of chunk sizes between min_size and max_size Review Comment: Yes, it is pretty close by default using `norm_factor=0`, `min_size=256KiB`, `max_size=1MiB`  Using `norm_factor=1`:  -- 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
