io.trino.execution.scheduler.faulttolerant.ByEagerParentOutputStatsEstimator Maven / Gradle / Ivy
/*
* Licensed 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 io.trino.execution.scheduler.faulttolerant;
import com.google.common.primitives.ImmutableLongArray;
import io.trino.Session;
import io.trino.execution.StageId;
import io.trino.execution.scheduler.faulttolerant.EventDrivenFaultTolerantQueryScheduler.StageExecution;
import java.util.Optional;
import java.util.function.Function;
public class ByEagerParentOutputStatsEstimator
implements OutputStatsEstimator
{
public static class Factory
implements OutputStatsEstimatorFactory
{
@Override
public OutputStatsEstimator create(Session session)
{
return new ByEagerParentOutputStatsEstimator();
}
}
@Override
public Optional getEstimatedOutputStats(StageExecution stageExecution, Function stageExecutionLookup, boolean parentEager)
{
if (!parentEager) {
return Optional.empty();
}
// use empty estimate as fallback for eager parents. It matches current logic of assessing if node should be processed eagerly or not.
// Currently, we use eager task exectuion only for stages with small FINAL LIMIT which implies small input from child stages (child stages will
// enforce small input via PARTIAL LIMIT)
int outputPartitionsCount = stageExecution.getSinkPartitioningScheme().getPartitionCount();
ImmutableLongArray.Builder estimateBuilder = ImmutableLongArray.builder(outputPartitionsCount);
for (int i = 0; i < outputPartitionsCount; ++i) {
estimateBuilder.add(0);
}
return Optional.of(new OutputStatsEstimateResult(estimateBuilder.build(), 0, "FOR_EAGER_PARENT", false));
}
}