npawar commented on a change in pull request #6466: URL: https://github.com/apache/incubator-pinot/pull/6466#discussion_r574162371
########## File path: pinot-broker/src/main/java/org/apache/pinot/broker/routing/segmentpruner/EmptySegmentPruner.java ########## @@ -0,0 +1,130 @@ +/** + * 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.broker.routing.segmentpruner; + +import java.util.ArrayList; +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.helix.AccessOption; +import org.apache.helix.ZNRecord; +import org.apache.helix.model.ExternalView; +import org.apache.helix.model.IdealState; +import org.apache.helix.store.zk.ZkHelixPropertyStore; +import org.apache.pinot.common.metadata.ZKMetadataProvider; +import org.apache.pinot.common.request.BrokerRequest; +import org.apache.pinot.common.utils.CommonConstants; +import org.apache.pinot.spi.config.table.TableConfig; +import org.slf4j.Logger; +import org.slf4j.LoggerFactory; + + +/** + * The {@code EmptySegmentPruner} prunes segments if they have 0 totalDocs. + * Does not prune segments with -1 total docs (that can be either error case or CONSUMING segment) + */ +public class EmptySegmentPruner implements SegmentPruner { + private static final Logger LOGGER = LoggerFactory.getLogger(EmptySegmentPruner.class); + + private final String _tableNameWithType; + private final ZkHelixPropertyStore<ZNRecord> _propertyStore; + private final String _segmentZKMetadataPathPrefix; + + private final Map<String, Long> _segmentTotalDocsMap = new HashMap<>(); + private final Set<String> _emptySegments = new HashSet<>(); + + public EmptySegmentPruner(TableConfig tableConfig, ZkHelixPropertyStore<ZNRecord> propertyStore) { + _tableNameWithType = tableConfig.getTableName(); + _propertyStore = propertyStore; + _segmentZKMetadataPathPrefix = ZKMetadataProvider.constructPropertyStorePathForResource(_tableNameWithType) + "/"; + } + + @Override + public void init(ExternalView externalView, IdealState idealState, Set<String> onlineSegments) { + // Bulk load info for all online segments + int numSegments = onlineSegments.size(); + List<String> segments = new ArrayList<>(numSegments); + List<String> segmentZKMetadataPaths = new ArrayList<>(numSegments); + for (String segment : onlineSegments) { + segments.add(segment); + segmentZKMetadataPaths.add(_segmentZKMetadataPathPrefix + segment); + } + List<ZNRecord> znRecords = _propertyStore.get(segmentZKMetadataPaths, null, AccessOption.PERSISTENT, false); + for (int i = 0; i < numSegments; i++) { + String segment = segments.get(i); + long totalDocs = extractTotalDocsFromSegmentZKMetaZNRecord(segment, znRecords.get(i)); + _segmentTotalDocsMap.put(segment, totalDocs); + if (totalDocs == 0) { + _emptySegments.add(segment); + } + } + } + + private long extractTotalDocsFromSegmentZKMetaZNRecord(String segment, @Nullable ZNRecord znRecord) { + if (znRecord == null) { + LOGGER.warn("Failed to find segment ZK metadata for segment: {}, table: {}", segment, _tableNameWithType); + return -1; + } + return znRecord.getLongField(CommonConstants.Segment.TOTAL_DOCS, -1); + } + + @Override + public synchronized void onExternalViewChange(ExternalView externalView, IdealState idealState, + Set<String> onlineSegments) { + // NOTE: We don't update all the segment ZK metadata for every external view change, but only the new added/removed + // ones. The refreshed segment ZK metadata change won't be picked up. + for (String segment : onlineSegments) { + _segmentTotalDocsMap.computeIfAbsent(segment, k -> { + long totalDocs = extractTotalDocsFromSegmentZKMetaZNRecord(k, + _propertyStore.get(_segmentZKMetadataPathPrefix + k, null, AccessOption.PERSISTENT)); + if (totalDocs == 0) { + _emptySegments.add(segment); + } + return totalDocs; + }); + } + _segmentTotalDocsMap.keySet().retainAll(onlineSegments); + _emptySegments.retainAll(onlineSegments); + } + + @Override + public synchronized void refreshSegment(String segment) { + long totalDocs = extractTotalDocsFromSegmentZKMetaZNRecord(segment, + _propertyStore.get(_segmentZKMetadataPathPrefix + segment, null, AccessOption.PERSISTENT)); + _segmentTotalDocsMap.put(segment, totalDocs); + if (totalDocs == 0) { + _emptySegments.add(segment); + } else { + _emptySegments.remove(segment); + } + } + + /** + * Prune out segments which are empty + */ + @Override + public Set<String> prune(BrokerRequest brokerRequest, Set<String> segments) { + Set<String> selectedSegments = new HashSet<>(segments); Review comment: i remembered why I'd done it that way. The segments set was immutable, and operating on it directly resulted in Unsupported Operation exception ---------------------------------------------------------------- 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. For queries about this service, please contact Infrastructure at: us...@infra.apache.org --------------------------------------------------------------------- To unsubscribe, e-mail: commits-unsubscr...@pinot.apache.org For additional commands, e-mail: commits-h...@pinot.apache.org
