private void addBlocks(
VolumeManager fs,
String host,
ArrayList<String> files,
Map<String, Long> totalBlocks,
Map<String, Long> localBlocks)
throws Exception {
long allBlocks = 0;
long matchingBlocks = 0;
if (!totalBlocks.containsKey(host)) {
totalBlocks.put(host, 0L);
localBlocks.put(host, 0L);
}
for (String file : files) {
Path filePath = new Path(file);
FileSystem ns = fs.getFileSystemByPath(filePath);
FileStatus fileStatus = ns.getFileStatus(filePath);
BlockLocation[] fileBlockLocations =
ns.getFileBlockLocations(fileStatus, 0, fileStatus.getLen());
for (BlockLocation blockLocation : fileBlockLocations) {
allBlocks++;
for (String location : blockLocation.getHosts()) {
HostAndPort hap = HostAndPort.fromParts(location, 0);
if (hap.getHostText().equals(host)) {
matchingBlocks++;
break;
}
}
}
}
totalBlocks.put(host, allBlocks + totalBlocks.get(host));
localBlocks.put(host, matchingBlocks + localBlocks.get(host));
}
public FileFragment(String tableName, Path uri, BlockLocation blockLocation) throws IOException {
this(
tableName,
uri,
blockLocation.getOffset(),
blockLocation.getLength(),
blockLocation.getHosts(),
null);
}
@SuppressWarnings("unchecked")
@Override
/**
* Splits the input collection into sets of files where each Map task gets about the same number
* of files
*/
public InputSplit[] getSplits(JobConf job, int numSplits) throws IOException {
Path[] paths = FileInputFormat.getInputPaths(job);
// HADOOP-1818: Manage splits only if there are paths
if (paths.length == 0) {
return new InputSplit[0];
}
if (numSplits > paths.length) {
numSplits = paths.length;
} else if (numSplits < 1) {
numSplits = 1;
}
logger.info("Allocating " + paths.length + " files across " + numSplits + " map tasks");
List<PositionAwareSplit<CombineFileSplit>> splits =
new ArrayList<PositionAwareSplit<CombineFileSplit>>(numSplits);
final int numPaths = paths.length;
long[] lengths = new long[numPaths];
TObjectLongHashMap<String>[] locations =
(TObjectLongHashMap<String>[]) Array.newInstance(TObjectLongHashMap.class, numPaths);
final FileSystem fs = FileSystem.get(job);
for (int i = 0; i < paths.length; i++) {
final FileStatus fss = fs.getFileStatus(paths[i]);
lengths[i] = fss.getLen();
final TObjectLongHashMap<String> location2size =
locations[i] = new TObjectLongHashMap<String>();
final long normalblocksize = fss.getBlockSize();
for (long offset = 0; offset < lengths[i]; offset += normalblocksize) {
final long blocksize = Math.min(offset + normalblocksize, lengths[i]);
final BlockLocation[] blockLocations = fs.getFileBlockLocations(fss, offset, blocksize);
for (BlockLocation bl : blockLocations) {
for (String host : bl.getHosts()) {
location2size.adjustOrPutValue(host, blocksize, blocksize);
}
}
}
}
// we need to over-estimate using ceil, to ensure that the last split is not /too/ big
final int numberOfFilesPerSplit = (int) Math.ceil((double) paths.length / (double) numSplits);
int pathsUsed = 0;
int splitnum = 0;
CombineFileSplit mfs;
// for each split except the last one (which may be smaller than numberOfFilesPerSplit)
while (pathsUsed < numPaths) {
/* caclulate split size for this task - usually numberOfFilesPerSplit, but
* less than this for the last split */
final int splitSizeForThisSplit =
numberOfFilesPerSplit + pathsUsed > numPaths
? numPaths - pathsUsed
: numberOfFilesPerSplit;
// arrays of information for split
Path[] splitPaths = new Path[splitSizeForThisSplit];
long[] splitLengths = new long[splitSizeForThisSplit];
long[] splitStarts = new long[splitSizeForThisSplit];
final TObjectLongHashMap<String> allLocationsForSplit = new TObjectLongHashMap<String>();
String[] splitLocations = null; // final recommended locations for this split.
for (int i = 0; i < splitSizeForThisSplit; i++) {
locations[pathsUsed + i].forEachEntry(
new TObjectLongProcedure<String>() {
public boolean execute(String a, long b) {
allLocationsForSplit.adjustOrPutValue(a, b, b);
return true;
}
});
if (allLocationsForSplit.size() <= 3) {
splitLocations = allLocationsForSplit.keys(new String[allLocationsForSplit.size()]);
} else {
String[] hosts = allLocationsForSplit.keys(new String[allLocationsForSplit.size()]);
Arrays.sort(
hosts,
new Comparator<String>() {
public int compare(String o1, String o2) {
long diffamount = allLocationsForSplit.get(o1) - allLocationsForSplit.get(o2);
if (diffamount > 0) {
return -1;
} else if (diffamount < 0) {
return 1;
}
return 0;
}
});
splitLocations = new String[3];
System.arraycopy(hosts, 0, splitLocations, 0, 3);
}
}
// copy information for this split
System.arraycopy(lengths, pathsUsed, splitLengths, 0, splitSizeForThisSplit);
System.arraycopy(paths, pathsUsed, splitPaths, 0, splitSizeForThisSplit);
// count the number of paths consumed
pathsUsed += splitSizeForThisSplit;
// make the actual split object
// logger.info("New split of size " + splitSizeForThisSplit);
mfs = new CombineFileSplit(job, splitPaths, splitStarts, splitLengths, splitLocations);
splits.add(new PositionAwareSplit<CombineFileSplit>(mfs, splitnum));
splitnum++;
}
if (!(pathsUsed == paths.length)) {
throw new IOException("Number of used paths does not equal total available paths!");
}
return splits.toArray(new PositionAwareSplit[splits.size()]);
}
