/**
* 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.drill.exec.store.schedule;
import java.io.IOException;
import java.util.Collection;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;
import java.util.concurrent.TimeUnit;
import org.apache.drill.exec.metrics.DrillMetrics;
import org.apache.drill.exec.proto.CoordinationProtos.DrillbitEndpoint;
import org.apache.drill.exec.store.dfs.easy.FileWork;
import org.apache.hadoop.fs.BlockLocation;
import org.apache.hadoop.fs.FileStatus;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import com.google.common.collect.Lists;
import com.codahale.metrics.MetricRegistry;
import com.codahale.metrics.Timer;
import com.google.common.base.Stopwatch;
import com.google.common.collect.ImmutableRangeMap;
import com.google.common.collect.Range;
import org.apache.hadoop.io.compress.CompressionCodecFactory;
public class BlockMapBuilder {
static final org.slf4j.Logger logger = org.slf4j.LoggerFactory.getLogger(BlockMapBuilder.class);
static final MetricRegistry metrics = DrillMetrics.getInstance();
static final String BLOCK_MAP_BUILDER_TIMER = MetricRegistry.name(BlockMapBuilder.class, "blockMapBuilderTimer");
private HashMap<Path,ImmutableRangeMap<Long,BlockLocation>> blockMapMap = new HashMap<>();
private Collection<DrillbitEndpoint> endpoints;
private FileSystem fs;
private HashMap<String,DrillbitEndpoint> endPointMap;
private CompressionCodecFactory codecFactory;
public BlockMapBuilder(FileSystem fs, Collection<DrillbitEndpoint> endpoints) {
this.fs = fs;
this.endpoints = endpoints;
codecFactory = new CompressionCodecFactory(fs.getConf());
buildEndpointMap();
}
private boolean compressed(FileStatus fileStatus) {
return codecFactory.getCodec(fileStatus.getPath()) != null;
}
public List<CompleteFileWork> generateFileWork(List<FileStatus> files, boolean blockify) throws IOException{
List<CompleteFileWork> work = Lists.newArrayList();
for(FileStatus f : files){
ImmutableRangeMap<Long,BlockLocation> rangeMap = getBlockMap(f);
if(!blockify || compressed(f)){
work.add(new CompleteFileWork(this.getEndpointByteMap(new FileStatusWork(f)), 0, f.getLen(), f.getPath().toString()));
continue;
}
for(Entry<Range<Long>, BlockLocation> l : rangeMap.asMapOfRanges().entrySet()){
work.add(new CompleteFileWork(this.getEndpointByteMap(new FileStatusWork(f)), l.getValue().getOffset(), l.getValue().getLength(), f.getPath().toString()));
}
}
return work;
}
private class FileStatusWork implements FileWork{
private FileStatus status;
public FileStatusWork(FileStatus status) {
if(status.isDir()) throw new IllegalStateException("FileStatus work only works with files, not directories.");
this.status = status;
}
@Override
public String getPath() {
return status.getPath().toString();
}
@Override
public long getStart() {
return 0;
}
@Override
public long getLength() {
return status.getLen();
}
}
private ImmutableRangeMap<Long,BlockLocation> buildBlockMap(Path path) throws IOException {
FileStatus status = fs.getFileStatus(path);
return buildBlockMap(status);
}
/**
* Builds a mapping of block locations to file byte range
*/
private ImmutableRangeMap<Long,BlockLocation> buildBlockMap(FileStatus status) throws IOException {
final Timer.Context context = metrics.timer(BLOCK_MAP_BUILDER_TIMER).time();
BlockLocation[] blocks;
ImmutableRangeMap<Long,BlockLocation> blockMap;
blocks = fs.getFileBlockLocations(status, 0 , status.getLen());
ImmutableRangeMap.Builder<Long, BlockLocation> blockMapBuilder = new ImmutableRangeMap.Builder<Long,BlockLocation>();
for (BlockLocation block : blocks) {
long start = block.getOffset();
long end = start + block.getLength();
Range<Long> range = Range.closedOpen(start, end);
blockMapBuilder = blockMapBuilder.put(range, block);
}
blockMap = blockMapBuilder.build();
blockMapMap.put(status.getPath(), blockMap);
context.stop();
return blockMap;
}
private ImmutableRangeMap<Long,BlockLocation> getBlockMap(Path path) throws IOException{
ImmutableRangeMap<Long,BlockLocation> blockMap = blockMapMap.get(path);
if(blockMap == null){
blockMap = buildBlockMap(path);
}
return blockMap;
}
private ImmutableRangeMap<Long,BlockLocation> getBlockMap(FileStatus status) throws IOException{
ImmutableRangeMap<Long,BlockLocation> blockMap = blockMapMap.get(status.getPath());
if(blockMap == null){
blockMap = buildBlockMap(status);
}
return blockMap;
}
/**
* For a given FileWork, calculate how many bytes are available on each on drillbit endpoint
*
* @param work the FileWork to calculate endpoint bytes for
* @throws IOException
*/
public EndpointByteMap getEndpointByteMap(FileWork work) throws IOException {
Stopwatch watch = new Stopwatch();
watch.start();
Path fileName = new Path(work.getPath());
ImmutableRangeMap<Long,BlockLocation> blockMap = getBlockMap(fileName);
EndpointByteMapImpl endpointByteMap = new EndpointByteMapImpl();
long start = work.getStart();
long end = start + work.getLength();
Range<Long> rowGroupRange = Range.closedOpen(start, end);
// Find submap of ranges that intersect with the rowGroup
ImmutableRangeMap<Long,BlockLocation> subRangeMap = blockMap.subRangeMap(rowGroupRange);
// Iterate through each block in this submap and get the host for the block location
for (Map.Entry<Range<Long>,BlockLocation> block : subRangeMap.asMapOfRanges().entrySet()) {
String[] hosts;
Range<Long> blockRange = block.getKey();
try {
hosts = block.getValue().getHosts();
} catch (IOException ioe) {
throw new RuntimeException("Failed to get hosts for block location", ioe);
}
Range<Long> intersection = rowGroupRange.intersection(blockRange);
long bytes = intersection.upperEndpoint() - intersection.lowerEndpoint();
// For each host in the current block location, add the intersecting bytes to the corresponding endpoint
for (String host : hosts) {
DrillbitEndpoint endpoint = getDrillBitEndpoint(host);
if(endpoint != null){
endpointByteMap.add(endpoint, bytes);
}else{
logger.debug("Failure finding Drillbit running on host {}. Skipping affinity to that host.", host);
}
}
}
logger.debug("FileWork group ({},{}) max bytes {}", work.getPath(), work.getStart(), endpointByteMap.getMaxBytes());
logger.debug("Took {} ms to set endpoint bytes", watch.stop().elapsed(TimeUnit.MILLISECONDS));
return endpointByteMap;
}
private DrillbitEndpoint getDrillBitEndpoint(String hostName) {
return endPointMap.get(hostName);
}
/**
* Builds a mapping of Drillbit endpoints to hostnames
*/
private void buildEndpointMap() {
Stopwatch watch = new Stopwatch();
watch.start();
endPointMap = new HashMap<String, DrillbitEndpoint>();
for (DrillbitEndpoint d : endpoints) {
String hostName = d.getAddress();
endPointMap.put(hostName, d);
}
watch.stop();
logger.debug("Took {} ms to build endpoint map", watch.elapsed(TimeUnit.MILLISECONDS));
}
}