org.apache.hadoop.hdfs.server.namenode.snapshot.FileDiffList 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.hdfs.server.namenode.snapshot;
import org.apache.hadoop.hdfs.server.blockmanagement.BlockInfo;
import org.apache.hadoop.hdfs.server.blockmanagement.BlockInfoContiguous;
import org.apache.hadoop.hdfs.server.common.HdfsServerConstants;
import org.apache.hadoop.hdfs.server.namenode.INode;
import org.apache.hadoop.hdfs.server.namenode.INode.BlocksMapUpdateInfo;
import org.apache.hadoop.hdfs.server.namenode.INodeFile;
import org.apache.hadoop.hdfs.server.namenode.INodeFileAttributes;
/** A list of FileDiffs for storing snapshot data. */
public class FileDiffList extends
AbstractINodeDiffList {
@Override
FileDiff createDiff(int snapshotId, INodeFile file) {
return new FileDiff(snapshotId, file);
}
@Override
INodeFileAttributes createSnapshotCopy(INodeFile currentINode) {
return new INodeFileAttributes.SnapshotCopy(currentINode);
}
public void destroyAndCollectSnapshotBlocks(
BlocksMapUpdateInfo collectedBlocks) {
for (FileDiff d : asList()) {
d.destroyAndCollectSnapshotBlocks(collectedBlocks);
}
}
public void saveSelf2Snapshot(int latestSnapshotId, INodeFile iNodeFile,
INodeFileAttributes snapshotCopy, boolean withBlocks) {
final FileDiff diff =
super.saveSelf2Snapshot(latestSnapshotId, iNodeFile, snapshotCopy);
if (withBlocks) { // Store blocks if this is the first update
BlockInfo[] blks = iNodeFile.getBlocks();
assert blks != null;
diff.setBlocks(blks);
}
}
public BlockInfo[] findEarlierSnapshotBlocks(int snapshotId) {
assert snapshotId != Snapshot.NO_SNAPSHOT_ID : "Wrong snapshot id";
if (snapshotId == Snapshot.CURRENT_STATE_ID) {
return null;
}
DiffList diffs = this.asList();
int i = diffs.binarySearch(snapshotId);
BlockInfo[] blocks = null;
for(i = i >= 0 ? i : -i-2; i >= 0; i--) {
blocks = diffs.get(i).getBlocks();
if(blocks != null) {
break;
}
}
return blocks;
}
public BlockInfo[] findLaterSnapshotBlocks(int snapshotId) {
assert snapshotId != Snapshot.NO_SNAPSHOT_ID : "Wrong snapshot id";
if (snapshotId == Snapshot.CURRENT_STATE_ID) {
return null;
}
DiffList diffs = this.asList();
int i = diffs.binarySearch(snapshotId);
BlockInfo[] blocks = null;
for (i = i >= 0 ? i+1 : -i-1; i < diffs.size(); i++) {
blocks = diffs.get(i).getBlocks();
if (blocks != null) {
break;
}
}
return blocks;
}
/**
* Copy blocks from the removed snapshot into the previous snapshot
* up to the file length of the latter.
* Collect unused blocks of the removed snapshot.
*/
void combineAndCollectSnapshotBlocks(
INode.ReclaimContext reclaimContext, INodeFile file, FileDiff removed) {
BlockInfo[] removedBlocks = removed.getBlocks();
if (removedBlocks == null) {
FileWithSnapshotFeature sf = file.getFileWithSnapshotFeature();
assert sf != null : "FileWithSnapshotFeature is null";
if(sf.isCurrentFileDeleted())
sf.collectBlocksAndClear(reclaimContext, file);
return;
}
int p = getPrior(removed.getSnapshotId(), true);
FileDiff earlierDiff = p == Snapshot.NO_SNAPSHOT_ID ? null : getDiffById(p);
// Copy blocks to the previous snapshot if not set already
if (earlierDiff != null) {
earlierDiff.setBlocks(removedBlocks);
}
BlockInfo[] earlierBlocks =
(earlierDiff == null ? new BlockInfoContiguous[]{} : earlierDiff.getBlocks());
// Find later snapshot (or file itself) with blocks
BlockInfo[] laterBlocks = findLaterSnapshotBlocks(removed.getSnapshotId());
laterBlocks = (laterBlocks == null) ? file.getBlocks() : laterBlocks;
// Skip blocks, which belong to either the earlier or the later lists
int i = 0;
for(; i < removedBlocks.length; i++) {
if(i < earlierBlocks.length && removedBlocks[i] == earlierBlocks[i])
continue;
if(i < laterBlocks.length && removedBlocks[i] == laterBlocks[i])
continue;
break;
}
// Check if last block is part of truncate recovery
BlockInfo lastBlock = file.getLastBlock();
BlockInfo dontRemoveBlock = null;
if (lastBlock != null && lastBlock.getBlockUCState().equals(
HdfsServerConstants.BlockUCState.UNDER_RECOVERY)) {
dontRemoveBlock = lastBlock.getUnderConstructionFeature()
.getTruncateBlock();
}
// Collect the remaining blocks of the file, ignoring truncate block
for (;i < removedBlocks.length; i++) {
if(dontRemoveBlock == null || !removedBlocks[i].equals(dontRemoveBlock)) {
reclaimContext.collectedBlocks().addDeleteBlock(removedBlocks[i]);
}
}
}
}