noob-se7en commented on code in PR #15261: URL: https://github.com/apache/pinot/pull/15261#discussion_r2009576026
########## pinot-core/src/main/java/org/apache/pinot/core/data/manager/realtime/SemaphoreAccessCoordinator.java: ########## @@ -0,0 +1,241 @@ +/** + * 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.core.data.manager.realtime; + +import com.google.common.base.Preconditions; +import java.util.Map; +import java.util.concurrent.Semaphore; +import java.util.concurrent.TimeUnit; +import java.util.concurrent.atomic.AtomicBoolean; +import java.util.concurrent.locks.Condition; +import java.util.concurrent.locks.Lock; +import java.util.concurrent.locks.ReentrantLock; +import javax.annotation.Nullable; +import org.apache.pinot.common.metadata.segment.SegmentZKMetadata; +import org.apache.pinot.common.utils.LLCSegmentName; +import org.apache.pinot.common.utils.helix.HelixHelper; +import org.apache.pinot.segment.local.data.manager.SegmentDataManager; +import org.apache.pinot.spi.config.table.ingestion.StreamIngestionConfig; +import org.apache.pinot.spi.utils.CommonConstants; +import org.slf4j.Logger; +import org.slf4j.LoggerFactory; + + +public class SemaphoreAccessCoordinator { + + private static final Logger LOGGER = LoggerFactory.getLogger(SemaphoreAccessCoordinator.class); + + private final Semaphore _semaphore; + private final boolean _enforceConsumptionInOrder; + private final Condition _condition; + private final Lock _lock; + private int _maxSegmentSeqNumLoaded = -1; + private boolean _relyOnIdealState = false; + private final RealtimeTableDataManager _realtimeTableDataManager; + private final AtomicBoolean _isFirstTransitionProcessed; + + public SemaphoreAccessCoordinator(Semaphore semaphore, boolean enforceConsumptionInOrder, + RealtimeTableDataManager realtimeTableDataManager) { + _semaphore = semaphore; + _lock = new ReentrantLock(); + _condition = _lock.newCondition(); + _enforceConsumptionInOrder = enforceConsumptionInOrder; + _realtimeTableDataManager = realtimeTableDataManager; + StreamIngestionConfig streamIngestionConfig = realtimeTableDataManager.getStreamIngestionConfig(); + boolean trackSegmentSeqNumber = false; + if (streamIngestionConfig != null) { + trackSegmentSeqNumber = streamIngestionConfig.isTrackSegmentSeqNumber(); + } + // if trackSegmentSeqNumber is false, server relies on ideal state to fetch previous segment to a segment. + if (!trackSegmentSeqNumber) { + _relyOnIdealState = true; + } + _isFirstTransitionProcessed = new AtomicBoolean(false); + } + + public void acquire(LLCSegmentName llcSegmentName) + throws InterruptedException { + + String segmentName = llcSegmentName.getSegmentName(); + + if (_enforceConsumptionInOrder) { + waitForPrevSegment(llcSegmentName); + } + + long startTimeMs = System.currentTimeMillis(); + while (!_semaphore.tryAcquire(5, TimeUnit.MINUTES)) { + LOGGER.warn("Failed to acquire partitionGroup consumer semaphore in: {} ms. Retrying.", + System.currentTimeMillis() - startTimeMs); + + // if segment is marked online/offline by any instance, just return the current offline -> consuming + // transition. + if (!_enforceConsumptionInOrder && !isSegmentInProgress(segmentName)) { + throw new SegmentAlreadyConsumedException("segment: " + segmentName + " status must be in progress"); + } + } + } + + public void release() { + _semaphore.release(); + } + + public Semaphore getSemaphore() { + return _semaphore; + } + + public void trackSegment(LLCSegmentName llcSegmentName) { + _lock.lock(); + try { + if (!_relyOnIdealState) { Review Comment: > 1. Never keep track of sequence number Is solution possible for this? If we are not relying on ideal state, Coordinator needs to have some state regarding which sequence number is in line to proceed ahead. Even with consumer signalling next segment, we need to maintain state as helix transitions can come up anytime in future. > 2. Use the combination of segmentDataManagerMap, recentlyDeletedSegments and ideal state to determine previous segment. Agree with `segmentDataManagerMap` and ideal state. But don't think we need `recentlyDeletedSegments`. -- 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: commits-unsubscr...@pinot.apache.org 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
