xiangfu0 commented on code in PR #19998: URL: https://github.com/apache/pinot/pull/19998#discussion_r4429206506
########## pinot-segment-spi/src/main/java/org/apache/pinot/segment/spi/index/metadata/MappedColumnMetadata.java: ########## @@ -0,0 +1,398 @@ +/** + * 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. + */ +package org.apache.pinot.segment.spi.index.metadata; + +import com.fasterxml.jackson.core.type.TypeReference; +import java.io.ByteArrayInputStream; +import java.io.DataInputStream; +import java.io.IOException; +import java.util.HashMap; +import java.util.HashSet; +import java.util.List; +import java.util.Map; +import java.util.Set; +import javax.annotation.Nullable; +import org.apache.pinot.segment.spi.ColumnMetadata; +import org.apache.pinot.segment.spi.compression.ChunkCompressionType; +import org.apache.pinot.segment.spi.index.IndexService; +import org.apache.pinot.segment.spi.index.IndexType; +import org.apache.pinot.segment.spi.partition.PartitionFunction; +import org.apache.pinot.segment.spi.partition.PartitionFunctionFactory; +import org.apache.pinot.spi.config.table.FieldConfig.EncodingType; +import org.apache.pinot.spi.data.FieldSpec; +import org.apache.pinot.spi.data.FieldSpec.DataType; +import org.apache.pinot.spi.utils.JsonUtils; + +/// A small view of one fixed record in [MappedSegmentMetadataStore]. No per-column values are copied into this view. +/// Data-source metadata delegates to this live view. Serving callers must hold the owning segment's acquired +/// reference for the full read; the segment manager's reference count delays destruction and unmapping until readers +/// release it. Standalone callers must keep the owning mapped metadata open. Buffer-backed reads after close throw. +public final class MappedColumnMetadata implements ColumnMetadata { + private final MappedSegmentMetadataStore _store; + private final int _ordinal; + @Nullable + private volatile PartitionFunction _partitionFunction; + private volatile boolean _partitionFunctionLoaded; + @Nullable + private volatile Set<Integer> _partitions; + private volatile boolean _partitionsLoaded; + @Nullable + private volatile Bounds _bounds; + @Nullable + private volatile IndexSize[] _indexes; + + private static final class Bounds { + @Nullable + private final Comparable<?> _minimum; + @Nullable + private final Comparable<?> _maximum; + + private Bounds(@Nullable Comparable<?> minimum, @Nullable Comparable<?> maximum) { + _minimum = minimum; + _maximum = maximum; + } + } + + MappedColumnMetadata(MappedSegmentMetadataStore store, int ordinal) { + _store = store; + _ordinal = ordinal; + } + + @Override + public FieldSpec getFieldSpec() { + // Field specs are shared across mapped segments; callers must treat the returned spec as read-only. + return _store.fieldSpec(_ordinal); + } + + @Override + public int getTotalDocs() { + return _store.getInt(_ordinal, MappedSegmentMetadataStore.TOTAL_DOCS); + } + + @Override + public int getCardinality() { + return _store.getInt(_ordinal, MappedSegmentMetadataStore.CARDINALITY); + } + + @Override + public boolean hasDictionary() { + return _store.flag(_ordinal, MappedSegmentMetadataStore.HAS_DICTIONARY); + } + + @Nullable + @Override + public EncodingType getForwardIndexEncoding() { + switch (_store.getInt(_ordinal, MappedSegmentMetadataStore.ENCODING)) { + case 0: + return null; + case 1: + return EncodingType.RAW; + case 2: + return EncodingType.DICTIONARY; + default: + throw new IllegalStateException("Invalid forward-index encoding"); + } + } + + @Override + public boolean isSorted() { + return _store.flag(_ordinal, MappedSegmentMetadataStore.SORTED); + } + + @Override + public boolean isNonNull() { + return _store.flag(_ordinal, MappedSegmentMetadataStore.NON_NULL); + } + + @Nullable + @Override + public Comparable<?> getMinValue() { + return bounds()._minimum; + } + + @Nullable + @Override + public Comparable<?> getMaxValue() { + return bounds()._maximum; + } + + private Bounds bounds() { + Bounds bounds = _bounds; + if (bounds == null) { + synchronized (this) { + bounds = _bounds; + if (bounds == null) { + bounds = new Bounds(_store.value(_ordinal, true), _store.value(_ordinal, false)); + _bounds = bounds; + } + } + } + return bounds; + } + + @Override + public boolean isMinMaxValueInvalid() { + return _store.flag(_ordinal, MappedSegmentMetadataStore.INVALID_MIN_MAX); + } + + @Override + public int getLengthOfShortestElement() { + return _store.getInt(_ordinal, MappedSegmentMetadataStore.SHORTEST); + } + + @Override + public int getLengthOfLongestElement() { + return _store.getInt(_ordinal, MappedSegmentMetadataStore.LONGEST); + } + + @Override + public boolean isAscii() { + return _store.flag(_ordinal, MappedSegmentMetadataStore.ASCII); + } + + @Override + public int getBitsPerElement() { + return _store.getInt(_ordinal, MappedSegmentMetadataStore.BITS); + } + + @Override + public int getTotalNumberOfEntries() { + return _store.getInt(_ordinal, MappedSegmentMetadataStore.TOTAL_ENTRIES); + } + + @Override + public int getMaxNumberOfMultiValues() { + return _store.getInt(_ordinal, MappedSegmentMetadataStore.MAX_MV); + } + + @Override + public int getMaxRowLengthInBytes() { + return _store.getInt(_ordinal, MappedSegmentMetadataStore.MAX_ROW); + } + + @Nullable + @Override + public PartitionFunction getPartitionFunction() { + if (!_partitionFunctionLoaded) { + synchronized (this) { + if (!_partitionFunctionLoaded) { + _partitionFunction = decodePartitionFunction(); + _partitionFunctionLoaded = true; + } + } + } + return _partitionFunction; + } + + @Nullable + private PartitionFunction decodePartitionFunction() { + byte[] bytes = _store.blob(_ordinal, MappedSegmentMetadataStore.PARTITION_FUNCTION); + if (bytes == null) { + return null; + } + try (DataInputStream input = new DataInputStream(new ByteArrayInputStream(bytes))) { + String name = MappedSegmentMetadataStore.readString(input); + int numPartitions = input.readInt(); + int configSize = input.readInt(); + Map<String, String> config = configSize != 0 ? new HashMap<>(configSize) : null; + for (int i = 0; i < configSize; i++) { + config.put(MappedSegmentMetadataStore.readString(input), MappedSegmentMetadataStore.readString(input)); + } + return PartitionFunctionFactory.getPartitionFunction(name, numPartitions, config); + } catch (IOException e) { + throw new IllegalStateException("Cannot decode partition function for " + getColumnName(), e); + } + } + + @Nullable + @Override + public Set<Integer> getPartitions() { + if (!_partitionsLoaded) { + synchronized (this) { + if (!_partitionsLoaded) { + _partitions = decodePartitions(); + _partitionsLoaded = true; + } + } + } + return _partitions; + } + + @Nullable + private Set<Integer> decodePartitions() { + byte[] bytes = _store.blob(_ordinal, MappedSegmentMetadataStore.PARTITIONS); + if (bytes == null) { + return null; + } + try (DataInputStream input = new DataInputStream(new ByteArrayInputStream(bytes))) { + int count = input.readInt(); + Set<Integer> partitions = new HashSet<>(count); + for (int i = 0; i < count; i++) { + partitions.add(input.readInt()); + } + return partitions; + } catch (IOException e) { + throw new IllegalStateException("Cannot decode partitions for " + getColumnName(), e); + } + } + + @Override + public boolean isAutoGenerated() { + return _store.flag(_ordinal, MappedSegmentMetadataStore.AUTO_GENERATED); + } + + @Override + public boolean isMaterializedChild() { + return getParentColumn() != null; + } + + @Nullable + @Override + public String getParentColumn() { + return _store.string(_ordinal, MappedSegmentMetadataStore.PARENT); + } + + @Nullable + @Override + public List<String> getSparseKeys() { + return readJson(MappedSegmentMetadataStore.SPARSE_KEYS, new TypeReference<List<String>>() { }); + } + + @Nullable + @Override + public Map<String, Integer> getSparseMultiValueKeys() { + return readJson(MappedSegmentMetadataStore.SPARSE_MULTI_VALUE_KEYS, + new TypeReference<Map<String, Integer>>() { }); + } + + @Nullable + @Override + public Map<String, DataType> getSparseKeyTypes() { + return readJson(MappedSegmentMetadataStore.SPARSE_KEY_TYPES, + new TypeReference<Map<String, DataType>>() { }); + } + + @Nullable + private <T> T readJson(int field, TypeReference<T> type) { + String json = _store.string(_ordinal, field); + if (json == null) { + return null; + } + try { + return JsonUtils.stringToObject(json, type); + } catch (IOException e) { + throw new IllegalStateException("Cannot decode OPEN_STRUCT metadata for " + getColumnName(), e); + } + } + + @Override + public int getNumIndexes() { + return _store.getInt(_ordinal, MappedSegmentMetadataStore.INDEX_COUNT); + } + + @Override + public short getIndexType(int position) { + return IndexService.getInstance().getNumericId(IndexService.getInstance().get(indexAt(position)._type)); + } + + @Override + public long getIndexSize(int position) { + return indexAt(position)._size; + } + + @Override + public long getIndexSizeFor(IndexType type) { + int count = getNumIndexes(); + for (int i = 0; i < count; i++) { + IndexSize entry = indexAt(i); + if (entry._type.equals(type.getId())) { + return entry._size; + } + } + return UNAVAILABLE; + } + + /// Kept for the segment-metadata REST JSON representation. + @SuppressWarnings("unused") + public Map<IndexType<?, ?, ?>, Long> getIndexSizeMap() { + Map<IndexType<?, ?, ?>, Long> sizes = new HashMap<>(); + int count = getNumIndexes(); + for (int i = 0; i < count; i++) { + IndexSize entry = indexAt(i); + sizes.put(IndexService.getInstance().get(entry._type), entry._size); + } + return sizes; + } + + private IndexSize indexAt(int position) { + IndexSize[] indexes = _indexes; + int count = indexes != null ? indexes.length : getNumIndexes(); + if (position < 0 || position >= count) { + throw new IndexOutOfBoundsException(position); + } + if (indexes == null) { + synchronized (this) { + indexes = _indexes; + if (indexes == null) { + byte[] bytes = _store.blob(_ordinal, MappedSegmentMetadataStore.INDEXES); + if (bytes == null) { + throw new IllegalStateException("Missing index sizes for " + getColumnName()); + } + indexes = new IndexSize[count]; + try (DataInputStream input = new DataInputStream(new ByteArrayInputStream(bytes))) { + for (int i = 0; i < count; i++) { + indexes[i] = new IndexSize(MappedSegmentMetadataStore.readString(input), input.readLong()); Review Comment: Measured on current head 47e02405cd with 32 complete synthetic v3 segments, each 1,000 INT columns and 100 rows, across three fresh JVMs per mode. The harness calls actual SegmentCompressionStatsReader.read(false) and read(true) for every segment, warms all column bounds and index sizes, and runs a min/max-pruned query before retained-heap collection. Post-warm heap increase was 30.57-30.62 MiB eager versus 26.57-26.69 MiB mapped, about 4 MiB or 13% less on this fixture. The PR description now includes the methods, load results, and limitations. Production-scale serving remains a separate open gate. -- 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]
