org.apache.hadoop.hdfs.server.datanode.fsdataset.impl.NativePmemMappedBlock Maven / Gradle / Ivy
/**
* 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.datanode.fsdataset.impl;
import org.apache.hadoop.classification.InterfaceAudience;
import org.apache.hadoop.classification.InterfaceStability;
import org.apache.hadoop.hdfs.ExtendedBlockId;
import org.apache.hadoop.io.nativeio.NativeIO;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.io.IOException;
/**
* Represents an HDFS block that is mapped to persistent memory by the DataNode.
*/
@InterfaceAudience.Private
@InterfaceStability.Unstable
public class NativePmemMappedBlock implements MappableBlock {
private static final Logger LOG =
LoggerFactory.getLogger(NativePmemMappedBlock.class);
private long pmemMappedAddress = -1L;
private long length;
private ExtendedBlockId key;
NativePmemMappedBlock(long pmemMappedAddress, long length,
ExtendedBlockId key) {
assert length > 0;
this.pmemMappedAddress = pmemMappedAddress;
this.length = length;
this.key = key;
}
@Override
public long getLength() {
return length;
}
@Override
public long getAddress() {
return pmemMappedAddress;
}
@Override
public ExtendedBlockId getKey() {
return key;
}
@Override
public void close() {
if (pmemMappedAddress != -1L) {
try {
String cacheFilePath =
PmemVolumeManager.getInstance().getCachePath(key);
// Current libpmem will report error when pmem_unmap is called with
// length not aligned with page size, although the length is returned
// by pmem_map_file.
boolean success =
NativeIO.POSIX.Pmem.unmapBlock(pmemMappedAddress, length);
if (!success) {
throw new IOException("Failed to unmap the mapped file from " +
"pmem address: " + pmemMappedAddress);
}
pmemMappedAddress = -1L;
FsDatasetUtil.deleteMappedFile(cacheFilePath);
LOG.info("Successfully uncached one replica:{} from persistent memory"
+ ", [cached path={}, length={}]", key, cacheFilePath, length);
} catch (IOException e) {
LOG.warn("IOException occurred for block {}!", key, e);
}
}
}
}