pvary commented on code in PR #10484: URL: https://github.com/apache/iceberg/pull/10484#discussion_r1698428895
########## flink/v1.19/flink/src/main/java/org/apache/iceberg/flink/maintenance/operator/TriggerManager.java: ########## @@ -0,0 +1,295 @@ +/* + * 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.iceberg.flink.maintenance.operator; + +import java.io.IOException; +import java.util.List; +import java.util.stream.Collectors; +import org.apache.flink.annotation.Internal; +import org.apache.flink.api.common.state.ListState; +import org.apache.flink.api.common.state.ListStateDescriptor; +import org.apache.flink.api.common.state.ValueState; +import org.apache.flink.api.common.state.ValueStateDescriptor; +import org.apache.flink.api.common.typeinfo.TypeInformation; +import org.apache.flink.api.common.typeinfo.Types; +import org.apache.flink.configuration.Configuration; +import org.apache.flink.metrics.Counter; +import org.apache.flink.runtime.state.FunctionInitializationContext; +import org.apache.flink.runtime.state.FunctionSnapshotContext; +import org.apache.flink.streaming.api.TimerService; +import org.apache.flink.streaming.api.checkpoint.CheckpointedFunction; +import org.apache.flink.streaming.api.functions.KeyedProcessFunction; +import org.apache.flink.util.Collector; +import org.apache.iceberg.SerializableTable; +import org.apache.iceberg.flink.TableLoader; +import org.apache.iceberg.relocated.com.google.common.base.Preconditions; +import org.apache.iceberg.relocated.com.google.common.collect.Lists; +import org.slf4j.Logger; +import org.slf4j.LoggerFactory; + +/** . */ +@Internal +class TriggerManager extends KeyedProcessFunction<Boolean, TableChange, Trigger> + implements CheckpointedFunction { + private static final Logger LOG = LoggerFactory.getLogger(TriggerManager.class); + + private final TableLoader tableLoader; + private final TriggerLockFactory lockFactory; + private final List<String> taskNames; + private final List<TriggerEvaluator> evaluators; + private final long minFireDelayMs; + private final long lockCheckDelayMs; + private final boolean clearLocks; + private transient Counter rateLimiterTriggeredCounter; + private transient Counter concurrentRunTriggeredCounter; + private transient Counter nothingToTriggerCounter; + private transient List<Counter> triggerCounters; + private transient ValueState<Long> nextEvaluationTime; + private transient ListState<TableChange> accumulatedChanges; + private transient ListState<Long> lastTriggerTimes; + private transient TriggerLockFactory.Lock lock; + private transient TriggerLockFactory.Lock recoveryLock; + private transient boolean isCleanUp = false; + private transient boolean inited = false; + private transient int startsFrom = 0; + + TriggerManager( + TableLoader tableLoader, + TriggerLockFactory lockFactory, + List<String> taskNames, + List<TriggerEvaluator> evaluators, + long minFireDelayMs, + long lockCheckDelayMs, + boolean clearLocks) { + Preconditions.checkNotNull(tableLoader, "Table loader should no be null"); + Preconditions.checkNotNull(lockFactory, "Lock factory should no be null"); + Preconditions.checkArgument( + evaluators != null && !evaluators.isEmpty(), "Evaluators should not be empty"); + Preconditions.checkArgument( + taskNames.size() == evaluators.size(), "Provide a name and evaluator for all of the tasks"); + Preconditions.checkArgument(minFireDelayMs > 0, "Minimum fire delay should be at least 1."); + Preconditions.checkArgument( + lockCheckDelayMs > 0, "Minimum lock delay rate should be at least 1."); + + this.tableLoader = tableLoader; + this.lockFactory = lockFactory; + this.taskNames = taskNames; + this.evaluators = evaluators; + this.minFireDelayMs = minFireDelayMs; + this.lockCheckDelayMs = lockCheckDelayMs; + this.clearLocks = clearLocks; + } + + @Override + public void open(Configuration parameters) throws Exception { + this.rateLimiterTriggeredCounter = + getRuntimeContext() + .getMetricGroup() + .addGroup(MetricConstants.GROUP_KEY, MetricConstants.GROUP_VALUE_DEFAULT) + .counter(MetricConstants.RATE_LIMITER_TRIGGERED); + this.concurrentRunTriggeredCounter = + getRuntimeContext() + .getMetricGroup() + .addGroup(MetricConstants.GROUP_KEY, MetricConstants.GROUP_VALUE_DEFAULT) + .counter(MetricConstants.CONCURRENT_RUN_TRIGGERED); + this.nothingToTriggerCounter = + getRuntimeContext() + .getMetricGroup() + .addGroup(MetricConstants.GROUP_KEY, MetricConstants.GROUP_VALUE_DEFAULT) + .counter(MetricConstants.NOTHING_TO_TRIGGER); + this.triggerCounters = + taskNames.stream() + .map( + name -> + getRuntimeContext() + .getMetricGroup() + .addGroup(MetricConstants.GROUP_KEY, name) + .counter(MetricConstants.TRIGGERED)) + .collect(Collectors.toList()); + + this.nextEvaluationTime = + getRuntimeContext() + .getState(new ValueStateDescriptor<>("triggerManagerNextTriggerTime", Types.LONG)); + this.accumulatedChanges = + getRuntimeContext() + .getListState( + new ListStateDescriptor<>( + "triggerManagerAccumulatedChange", TypeInformation.of(TableChange.class))); + this.lastTriggerTimes = + getRuntimeContext() + .getListState(new ListStateDescriptor<>("triggerManagerLastTriggerTime", Types.LONG)); + } + + @Override + public void snapshotState(FunctionSnapshotContext context) throws Exception { + // Do nothing + } + + @Override + public void initializeState(FunctionInitializationContext context) { + LOG.info("Initializing state restored: {}, clearLocks: {}", context.isRestored(), clearLocks); + this.lock = lockFactory.createLock(); + this.recoveryLock = lockFactory.createRecoveryLock(); + if (context.isRestored()) { + isCleanUp = true; + } else if (clearLocks) { + // Remove old lock if we are not restoring the job + lock.unlock(); + } + } + + @Override + public void processElement(TableChange change, Context ctx, Collector<Trigger> out) + throws Exception { + long current = ctx.timerService().currentProcessingTime(); + Long nextTime = nextEvaluationTime.value(); + init(out, ctx.timerService(), current); + + // Add the new changes to the already accumulated ones + List<TableChange> accumulated = Lists.newArrayList(accumulatedChanges.get()); + accumulated.forEach(tableChange -> tableChange.merge(change)); + accumulatedChanges.update(accumulated); + + if (nextTime == null) { + checkAndFire(current, ctx.timerService(), out); + } else { + LOG.info( + "Trigger manager rate limiter triggered current: {}, next: {}, accumulated changes: {}", + current, + nextTime, + accumulated); + rateLimiterTriggeredCounter.inc(); + } + } + + @Override + public void onTimer(long timestamp, OnTimerContext ctx, Collector<Trigger> out) throws Exception { + init(out, ctx.timerService(), timestamp); + nextEvaluationTime.clear(); + checkAndFire(ctx.timerService().currentProcessingTime(), ctx.timerService(), out); + } + + private void checkAndFire(long current, TimerService timerService, Collector<Trigger> out) + throws Exception { + if (isCleanUp) { + if (recoveryLock.isHeld()) { + LOG.debug("The cleanup lock is still held at {}", current); + schedule(timerService, current + lockCheckDelayMs); + return; + } else { + LOG.info("The cleanup is finished at {}", current); + isCleanUp = false; + } + } + + List<TableChange> changes = Lists.newArrayList(accumulatedChanges.get()); + List<Long> times = Lists.newArrayList(lastTriggerTimes.get()); + Integer taskToStart = nextTrigger(evaluators, changes, times, current, startsFrom); + if (taskToStart == null) { + // Nothing to execute + if (startsFrom == 0) { + nothingToTriggerCounter.inc(); + LOG.debug("Nothing to execute at {} for collected: {}", current, changes); + } + + startsFrom = 0; + return; + } + + if (lock.tryLock()) { + TableChange change = changes.get(taskToStart); + SerializableTable table = + (SerializableTable) SerializableTable.copyOf(tableLoader.loadTable()); + out.collect(Trigger.create(current, table, taskToStart)); + LOG.debug("Fired event with time: {}, collected: {} for {}", current, change, table.name()); + triggerCounters.get(taskToStart).inc(); + changes.set(taskToStart, TableChange.empty()); + accumulatedChanges.update(changes); + schedule(timerService, current + minFireDelayMs); + startsFrom = taskToStart + 1; + } else { + // The lock is already held by someone + LOG.info("Delaying task on failed lock check: {}", current); + + startsFrom = taskToStart; + concurrentRunTriggeredCounter.inc(); + schedule(timerService, current + lockCheckDelayMs); + } + + timerService.registerProcessingTimeTimer(nextEvaluationTime.value()); + } + + private void schedule(TimerService timerService, long time) throws IOException { + nextEvaluationTime.update(time); + timerService.registerProcessingTimeTimer(time); + } + + private static Integer nextTrigger( + List<TriggerEvaluator> evaluators, + List<TableChange> changes, + List<Long> lastTriggerTimes, + long currentTime, + int startPos) { + int normalizedStartingPos = startPos % evaluators.size(); + int current = normalizedStartingPos; + do { + if (evaluators + .get(current) + .check(changes.get(current), lastTriggerTimes.get(current), currentTime)) { + return current; + } + + current = (current + 1) % evaluators.size(); + } while (current != normalizedStartingPos); + + return null; + } + + private void init(Collector<Trigger> out, TimerService timerService, long current) + throws Exception { + if (!inited) { + // Initialize with empty changes and current timestamp + if (!accumulatedChanges.get().iterator().hasNext()) { + List<TableChange> changes = Lists.newArrayListWithCapacity(evaluators.size()); + List<Long> triggerTimes = Lists.newArrayListWithCapacity(evaluators.size()); + for (int i = 0; i < evaluators.size(); ++i) { + changes.add(TableChange.empty()); + triggerTimes.add(current); + } + + accumulatedChanges.update(changes); + lastTriggerTimes.update(triggerTimes); + } + + if (isCleanUp) { + // When the job state is restored, there could be ongoing tasks. + // To prevent collision with the new triggers the following is done: + // - add a cleanup lock + // - fire a clean-up trigger + // This ensures that the tasks of the previous trigger are executed, and the lock is removed + // in the end. + recoveryLock.tryLock(); Review Comment: Added a comment like this: ``` The result of the 'tryLock' is ignored as an already existing lock prevents collisions as well ``` > if tryLock failed, it is fine to send the Trigger.cleanUp event? Consider the situation that we tried to recover a failed job, created the recovery lock, but the job failed again before finishing the lock cleanup. In this case if we try to recover the failed job again, then we will have a lock, but no `Trigger.cleanUp` in the pipeline, so we need to fire a `Trigger.cleanUp` event, as the `state` of the table could be different from the `state` of the Flink job we are recovering. -- 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: issues-unsubscr...@iceberg.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org --------------------------------------------------------------------- To unsubscribe, e-mail: issues-unsubscr...@iceberg.apache.org For additional commands, e-mail: issues-h...@iceberg.apache.org
