ChenSammi commented on code in PR #8972: URL: https://github.com/apache/ozone/pull/8972#discussion_r2306924689
########## hadoop-hdds/container-service/src/main/java/org/apache/hadoop/ozone/container/diskbalancer/VolumeDataDensityCalculation.java: ########## @@ -0,0 +1,83 @@ +/* + * 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.hadoop.ozone.container.diskbalancer; + +import com.google.common.base.Preconditions; +import java.util.Map; +import org.apache.hadoop.hdds.fs.SpaceUsageSource; +import org.apache.hadoop.ozone.container.common.utils.StorageVolumeUtil; +import org.apache.hadoop.ozone.container.common.volume.HddsVolume; +import org.apache.hadoop.ozone.container.common.volume.MutableVolumeSet; +import org.slf4j.Logger; +import org.slf4j.LoggerFactory; + +/** + * Standalone utility class for calculating VolumeDataDensity. + * This class uses the same logic as DefaultVolumeChoosingPolicy to ensure + * consistency between operational balancing decisions and reporting. + * + * This calculation is independent and can be used by any component that needs + * to calculate volume density without depending on DiskBalancerService. + */ +public final class VolumeDataDensityCalculation { + + private static final Logger LOG = LoggerFactory.getLogger(VolumeDataDensityCalculation.class); + + private VolumeDataDensityCalculation() { + } + + /** + * Calculate VolumeDataDensity using the same logic as DefaultVolumeChoosingPolicy. + * This ensures consistency between operational balancing decisions and reporting. + * + * @param volumeSet The MutableVolumeSet containing all volumes + * @param deltaMap Map of volume to delta sizes (ongoing operations), can be null + * @return VolumeDataDensity sum across all volumes + */ + public static double calculate(MutableVolumeSet volumeSet, Map<HddsVolume, Long> deltaMap) { + if (volumeSet == null) { + LOG.warn("VolumeSet is null, returning 0.0 for VolumeDataDensity"); + return 0.0; + } + + try { + double volumeDensitySum = 0.0; + + // Get ideal usage + double idealUsage = volumeSet.getIdealUsage(); + + // Calculate density for each volume + for (HddsVolume volume : StorageVolumeUtil.getHddsVolumesList(volumeSet.getVolumesList())) { + SpaceUsageSource usage = volume.getCurrentUsage(); + Preconditions.checkArgument(usage.getCapacity() != 0); + + long deltaSize = (deltaMap != null) ? deltaMap.getOrDefault(volume, 0L) : 0L; + double currentUsage = (double)((usage.getCapacity() - usage.getAvailable()) + + deltaSize + volume.getCommittedBytes()) / usage.getCapacity(); + + // Calculate density as absolute difference from ideal usage + double volumeDensity = Math.abs(currentUsage - idealUsage); + volumeDensitySum += volumeDensity; + } + return volumeDensitySum; + } catch (Exception e) { + LOG.error("Error calculating VolumeDataDensity", e); + return 0.0; Review Comment: Let's change it to -1.0, to represent that VolumeDataDensity is not available. -- 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]
