org.apache.hadoop.hbase.regionserver.querymatcher.DropDeletesCompactionScanQueryMatcher Maven / Gradle / Ivy
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/**
* 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.hbase.regionserver.querymatcher;
import org.apache.hadoop.hbase.Cell;
import org.apache.hadoop.hbase.KeepDeletedCells;
import org.apache.hadoop.hbase.classification.InterfaceAudience;
import org.apache.hadoop.hbase.regionserver.DeleteTracker;
import org.apache.hadoop.hbase.regionserver.ScanInfo;
/**
* A query matcher for compaction which can drop delete markers.
*/
@InterfaceAudience.Private
public abstract class DropDeletesCompactionScanQueryMatcher extends CompactionScanQueryMatcher {
/**
* By default, when hbase.hstore.time.to.purge.deletes is 0ms, a delete marker is always removed
* during a major compaction. If set to non-zero value then major compaction will try to keep a
* delete marker around for the given number of milliseconds. We want to keep the delete markers
* around a bit longer because old puts might appear out-of-order. For example, during log
* replication between two clusters.
*
* If the delete marker has lived longer than its column-family's TTL then the delete marker will
* be removed even if time.to.purge.deletes has not passed. This is because all the Puts that this
* delete marker can influence would have also expired. (Removing of delete markers on col family
* TTL will not happen if min-versions is set to non-zero)
*
* But, if time.to.purge.deletes has not expired then a delete marker will not be removed just
* because there are no Puts that it is currently influencing. This is because Puts, that this
* delete can influence. may appear out of order.
*/
protected final long timeToPurgeDeletes;
/**
* Oldest put in any of the involved store files Used to decide whether it is ok to delete family
* delete marker of this store keeps deleted KVs.
*/
protected final long earliestPutTs;
protected DropDeletesCompactionScanQueryMatcher(ScanInfo scanInfo, DeleteTracker deletes,
long readPointToUse, long earliestPutTs, long oldestUnexpiredTS, long now) {
super(scanInfo, deletes, readPointToUse, oldestUnexpiredTS, now);
this.timeToPurgeDeletes = scanInfo.getTimeToPurgeDeletes();
this.earliestPutTs = earliestPutTs;
}
protected final MatchCode tryDropDelete(Cell cell) {
long timestamp = cell.getTimestamp();
// If it is not the time to drop the delete marker, just return
if (timeToPurgeDeletes > 0 && now - timestamp <= timeToPurgeDeletes) {
return MatchCode.INCLUDE;
}
if (keepDeletedCells == KeepDeletedCells.TRUE
|| (keepDeletedCells == KeepDeletedCells.TTL && timestamp >= oldestUnexpiredTS)) {
// If keepDeletedCell is true, or the delete marker is not expired yet, we should include it
// in version counting to see if we can drop it. The only exception is that, we can make
// sure that no put is older than this delete marker. And under this situation, all later
// cells of this column(must be delete markers) can be skipped.
if (timestamp < earliestPutTs) {
return columns.getNextRowOrNextColumn(cell.getQualifierArray(), cell.getQualifierOffset(),
cell.getQualifierLength());
} else {
return null;
}
} else {
return MatchCode.SKIP;
}
}
}