sodonnel commented on code in PR #4227: URL: https://github.com/apache/ozone/pull/4227#discussion_r1101379624
########## hadoop-hdds/server-scm/src/main/java/org/apache/hadoop/hdds/scm/container/replication/health/RatisUnhealthyReplicationCheckHandler.java: ########## @@ -0,0 +1,193 @@ +/** + * 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 + * <p> + * http://www.apache.org/licenses/LICENSE-2.0 + * <p> + * 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.hdds.scm.container.replication.health; + +import com.google.common.annotations.VisibleForTesting; +import org.apache.hadoop.hdds.scm.container.ContainerInfo; +import org.apache.hadoop.hdds.scm.container.ReplicationManagerReport; +import org.apache.hadoop.hdds.scm.container.replication.ContainerCheckRequest; +import org.apache.hadoop.hdds.scm.container.replication.ContainerHealthResult; +import org.apache.hadoop.hdds.scm.container.replication.RatisContainerReplicaCount; +import org.slf4j.Logger; +import org.slf4j.LoggerFactory; + + +import static org.apache.hadoop.hdds.protocol.proto.HddsProtos.ReplicationType.RATIS; + +/** + * This class handles UNHEALTHY RATIS replicas. Its responsibilities include: + * <ul> + * <li>If only unhealthy replicas exist, check if there are replication + * factor number of replicas and queue them for under/over replication if + * needed. + * </li> + * <li>If there is perfect replication of healthy replicas, remove any + * excess unhealthy replicas. + * </li> + * </ul> + */ +public class RatisUnhealthyReplicationCheckHandler extends AbstractCheck { + public static final Logger LOG = LoggerFactory.getLogger( + RatisUnhealthyReplicationCheckHandler.class); + + @Override + public boolean handle(ContainerCheckRequest request) { + if (request.getContainerInfo().getReplicationType() != RATIS) { + // This handler is only for Ratis containers. + return false; + } + ReplicationManagerReport report = request.getReport(); + ContainerInfo container = request.getContainerInfo(); + + /* + First, verify there's perfect replication without considering UNHEALTHY + replicas. + */ + if (!verifyPerfectReplication(request)) { + return false; + } + + // Now, consider UNHEALTHY replicas when calculating replication status + RatisContainerReplicaCount replicaCount = + new RatisContainerReplicaCount(container, + request.getContainerReplicas(), request.getPendingOps(), + request.getMaintenanceRedundancy(), true); + if (replicaCount.getUnhealthyReplicaCount() == 0) { + LOG.info("No UNHEALTHY replicas are present for container {} with " + + "replicas [{}].", container, request.getContainerReplicas()); + return false; + } else { + LOG.debug("Container {} has UNHEALTHY replicas. Checking its " + + "replication status.", container); + report.incrementAndSample(ReplicationManagerReport.HealthState.UNHEALTHY, + container.containerID()); + } + + ContainerHealthResult health = checkReplication(request); + if (health.getHealthState() + == ContainerHealthResult.HealthState.UNDER_REPLICATED) { + ContainerHealthResult.UnderReplicatedHealthResult underHealth + = ((ContainerHealthResult.UnderReplicatedHealthResult) health); + report.incrementAndSample( + ReplicationManagerReport.HealthState.UNDER_REPLICATED, + container.containerID()); + LOG.debug("Container {} is Under Replicated. isReplicatedOkAfterPending" + + " is [{}]. isUnrecoverable is [{}]. hasHealthyReplicas is [{}].", + container, + underHealth.isReplicatedOkAfterPending(), + underHealth.isUnrecoverable(), underHealth.hasHealthyReplicas()); + + if (!underHealth.isReplicatedOkAfterPending()) { + request.getReplicationQueue().enqueue(underHealth); + } + return true; + } + + if (health.getHealthState() + == ContainerHealthResult.HealthState.OVER_REPLICATED) { + report.incrementAndSample( + ReplicationManagerReport.HealthState.OVER_REPLICATED, + container.containerID()); + ContainerHealthResult.OverReplicatedHealthResult overHealth + = ((ContainerHealthResult.OverReplicatedHealthResult) health); + LOG.debug("Container {} is Over Replicated. isReplicatedOkAfterPending" + + " is [{}]. hasMismatchedReplicas is [{}]", container, + overHealth.isReplicatedOkAfterPending(), + overHealth.hasMismatchedReplicas()); + + if (!overHealth.isReplicatedOkAfterPending()) { + request.getReplicationQueue().enqueue(overHealth); + } + return true; + } + + return false; + } + + /** + * Verify there's no under or over replication if only healthy replicas are + * considered, or that there are no healthy replicas. + * @return true if there's no under/over replication considering healthy + * replicas + */ + private boolean verifyPerfectReplication(ContainerCheckRequest request) { + RatisContainerReplicaCount replicaCountWithoutUnhealthy = + new RatisContainerReplicaCount(request.getContainerInfo(), + request.getContainerReplicas(), request.getPendingOps(), + request.getMaintenanceRedundancy(), false); + + if (replicaCountWithoutUnhealthy.getHealthyReplicaCount() == 0) { + return true; + } + if (!replicaCountWithoutUnhealthy.isSufficientlyReplicated() || + replicaCountWithoutUnhealthy.isOverReplicated()) { + LOG.info("Checking replication for container {} without considering " + + "UNHEALTHY replicas. isSufficientlyReplicated is [{}]. " + + "isOverReplicated is [{}]. Returning false because there should" + + " be perfect replication for this handler to work.", Review Comment: Yea, should be debug I think. -- 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]
