org.elasticsearch.cluster.routing.allocation.decider.SnapshotInProgressAllocationDecider Maven / Gradle / Ivy
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* the Apache License, Version 2.0 (the "License"); you may
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* 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,
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package org.elasticsearch.cluster.routing.allocation.decider;
import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;
import org.elasticsearch.cluster.SnapshotsInProgress;
import org.elasticsearch.cluster.routing.RoutingNode;
import org.elasticsearch.cluster.routing.ShardRouting;
import org.elasticsearch.cluster.routing.allocation.RoutingAllocation;
/**
* This {@link org.elasticsearch.cluster.routing.allocation.decider.AllocationDecider} prevents shards that
* are currently been snapshotted to be moved to other nodes.
*/
public class SnapshotInProgressAllocationDecider extends AllocationDecider {
private static final Logger logger = LogManager.getLogger(SnapshotInProgressAllocationDecider.class);
public static final String NAME = "snapshot_in_progress";
/**
* Returns a {@link Decision} whether the given shard routing can be
* re-balanced to the given allocation. The default is
* {@link Decision#ALWAYS}.
*/
@Override
public Decision canRebalance(ShardRouting shardRouting, RoutingAllocation allocation) {
return canMove(shardRouting, allocation);
}
/**
* Returns a {@link Decision} whether the given shard routing can be
* allocated on the given node. The default is {@link Decision#ALWAYS}.
*/
@Override
public Decision canAllocate(ShardRouting shardRouting, RoutingNode node, RoutingAllocation allocation) {
return canMove(shardRouting, allocation);
}
private Decision canMove(ShardRouting shardRouting, RoutingAllocation allocation) {
if (shardRouting.primary()) {
// Only primary shards are snapshotted
SnapshotsInProgress snapshotsInProgress = allocation.custom(SnapshotsInProgress.TYPE);
if (snapshotsInProgress == null || snapshotsInProgress.entries().isEmpty()) {
// Snapshots are not running
return allocation.decision(Decision.YES, NAME, "no snapshots are currently running");
}
for (SnapshotsInProgress.Entry snapshot : snapshotsInProgress.entries()) {
SnapshotsInProgress.ShardSnapshotStatus shardSnapshotStatus = snapshot.shards().get(shardRouting.shardId());
if (shardSnapshotStatus != null && !shardSnapshotStatus.state().completed() && shardSnapshotStatus.nodeId() != null &&
shardSnapshotStatus.nodeId().equals(shardRouting.currentNodeId())) {
if (logger.isTraceEnabled()) {
logger.trace("Preventing snapshotted shard [{}] from being moved away from node [{}]",
shardRouting.shardId(), shardSnapshotStatus.nodeId());
}
return allocation.decision(Decision.THROTTLE, NAME,
"waiting for snapshotting of shard [%s] to complete on this node [%s]",
shardRouting.shardId(), shardSnapshotStatus.nodeId());
}
}
}
return allocation.decision(Decision.YES, NAME, "the shard is not being snapshotted");
}
}