private void handleSampling(DriverContext context, MapWork mWork, JobConf job, HiveConf conf)
throws Exception {
assert mWork.getAliasToWork().keySet().size() == 1;
String alias = mWork.getAliases().get(0);
Operator<?> topOp = mWork.getAliasToWork().get(alias);
PartitionDesc partDesc = mWork.getAliasToPartnInfo().get(alias);
ArrayList<String> paths = mWork.getPaths();
ArrayList<PartitionDesc> parts = mWork.getPartitionDescs();
List<Path> inputPaths = new ArrayList<Path>(paths.size());
for (String path : paths) {
inputPaths.add(new Path(path));
}
Path tmpPath = context.getCtx().getExternalTmpPath(inputPaths.get(0));
Path partitionFile = new Path(tmpPath, ".partitions");
ShimLoader.getHadoopShims().setTotalOrderPartitionFile(job, partitionFile);
PartitionKeySampler sampler = new PartitionKeySampler();
if (mWork.getSamplingType() == MapWork.SAMPLING_ON_PREV_MR) {
console.printInfo("Use sampling data created in previous MR");
// merges sampling data from previous MR and make partition keys for total sort
for (Path path : inputPaths) {
FileSystem fs = path.getFileSystem(job);
for (FileStatus status : fs.globStatus(new Path(path, ".sampling*"))) {
sampler.addSampleFile(status.getPath(), job);
}
}
} else if (mWork.getSamplingType() == MapWork.SAMPLING_ON_START) {
console.printInfo("Creating sampling data..");
assert topOp instanceof TableScanOperator;
TableScanOperator ts = (TableScanOperator) topOp;
FetchWork fetchWork;
if (!partDesc.isPartitioned()) {
assert paths.size() == 1;
fetchWork = new FetchWork(inputPaths.get(0), partDesc.getTableDesc());
} else {
fetchWork = new FetchWork(inputPaths, parts, partDesc.getTableDesc());
}
fetchWork.setSource(ts);
// random sampling
FetchOperator fetcher = PartitionKeySampler.createSampler(fetchWork, conf, job, ts);
try {
ts.initialize(conf, new ObjectInspector[] {fetcher.getOutputObjectInspector()});
OperatorUtils.setChildrenCollector(ts.getChildOperators(), sampler);
while (fetcher.pushRow()) {}
} finally {
fetcher.clearFetchContext();
}
} else {
throw new IllegalArgumentException("Invalid sampling type " + mWork.getSamplingType());
}
sampler.writePartitionKeys(partitionFile, conf, job);
}
public static void setChildrenCollector(
List<Operator<? extends OperatorDesc>> childOperators, OutputCollector out) {
if (childOperators == null) {
return;
}
for (Operator<? extends OperatorDesc> op : childOperators) {
if (op.getName().equals(ReduceSinkOperator.getOperatorName())) {
op.setOutputCollector(out);
} else {
setChildrenCollector(op.getChildOperators(), out);
}
}
}
public static void setChildrenCollector(
List<Operator<? extends OperatorDesc>> childOperators, Map<String, OutputCollector> outMap) {
if (childOperators == null) {
return;
}
for (Operator<? extends OperatorDesc> op : childOperators) {
if (op.getName().equals(ReduceSinkOperator.getOperatorName())) {
ReduceSinkOperator rs = ((ReduceSinkOperator) op);
if (outMap.containsKey(rs.getConf().getOutputName())) {
LOG.info("Setting output collector: " + rs + " --> " + rs.getConf().getOutputName());
rs.setOutputCollector(outMap.get(rs.getConf().getOutputName()));
}
} else {
setChildrenCollector(op.getChildOperators(), outMap);
}
}
}
@Override
@SuppressWarnings("unchecked")
public void init(JobConf job, OutputCollector output, Reporter reporter) throws Exception {
perfLogger.PerfLogBegin(CLASS_NAME, PerfLogger.SPARK_INIT_OPERATORS);
super.init(job, output, reporter);
rowObjectInspector = new ObjectInspector[Byte.MAX_VALUE];
ObjectInspector[] valueObjectInspector = new ObjectInspector[Byte.MAX_VALUE];
ObjectInspector keyObjectInspector;
ReduceWork gWork = Utilities.getReduceWork(job);
reducer = gWork.getReducer();
vectorized = gWork.getVectorMode();
reducer.setParentOperators(null); // clear out any parents as reducer is the
// root
isTagged = gWork.getNeedsTagging();
try {
keyTableDesc = gWork.getKeyDesc();
inputKeyDeserializer = ReflectionUtils.newInstance(keyTableDesc.getDeserializerClass(), null);
SerDeUtils.initializeSerDe(inputKeyDeserializer, null, keyTableDesc.getProperties(), null);
keyObjectInspector = inputKeyDeserializer.getObjectInspector();
valueTableDesc = new TableDesc[gWork.getTagToValueDesc().size()];
if (vectorized) {
final int maxTags = gWork.getTagToValueDesc().size();
keyStructInspector = (StructObjectInspector) keyObjectInspector;
batches = new VectorizedRowBatch[maxTags];
valueStructInspectors = new StructObjectInspector[maxTags];
valueStringWriters = new List[maxTags];
keysColumnOffset = keyStructInspector.getAllStructFieldRefs().size();
buffer = new DataOutputBuffer();
}
for (int tag = 0; tag < gWork.getTagToValueDesc().size(); tag++) {
// We should initialize the SerDe with the TypeInfo when available.
valueTableDesc[tag] = gWork.getTagToValueDesc().get(tag);
inputValueDeserializer[tag] =
ReflectionUtils.newInstance(valueTableDesc[tag].getDeserializerClass(), null);
SerDeUtils.initializeSerDe(
inputValueDeserializer[tag], null, valueTableDesc[tag].getProperties(), null);
valueObjectInspector[tag] = inputValueDeserializer[tag].getObjectInspector();
ArrayList<ObjectInspector> ois = new ArrayList<ObjectInspector>();
if (vectorized) {
/* vectorization only works with struct object inspectors */
valueStructInspectors[tag] = (StructObjectInspector) valueObjectInspector[tag];
ObjectPair<VectorizedRowBatch, StandardStructObjectInspector> pair =
VectorizedBatchUtil.constructVectorizedRowBatch(
keyStructInspector,
valueStructInspectors[tag],
gWork.getVectorScratchColumnTypeMap());
batches[tag] = pair.getFirst();
final int totalColumns =
keysColumnOffset + valueStructInspectors[tag].getAllStructFieldRefs().size();
valueStringWriters[tag] = new ArrayList<VectorExpressionWriter>(totalColumns);
valueStringWriters[tag].addAll(
Arrays.asList(
VectorExpressionWriterFactory.genVectorStructExpressionWritables(
keyStructInspector)));
valueStringWriters[tag].addAll(
Arrays.asList(
VectorExpressionWriterFactory.genVectorStructExpressionWritables(
valueStructInspectors[tag])));
rowObjectInspector[tag] = pair.getSecond();
} else {
ois.add(keyObjectInspector);
ois.add(valueObjectInspector[tag]);
// reducer.setGroupKeyObjectInspector(keyObjectInspector);
rowObjectInspector[tag] =
ObjectInspectorFactory.getStandardStructObjectInspector(
Utilities.reduceFieldNameList, ois);
}
}
} catch (Exception e) {
throw new RuntimeException(e);
}
ExecMapperContext execContext = new ExecMapperContext(job);
localWork = gWork.getMapRedLocalWork();
execContext.setJc(jc);
execContext.setLocalWork(localWork);
reducer.passExecContext(execContext);
reducer.setReporter(rp);
OperatorUtils.setChildrenCollector(
Arrays.<Operator<? extends OperatorDesc>>asList(reducer), output);
// initialize reduce operator tree
try {
LOG.info(reducer.dump(0));
reducer.initialize(jc, rowObjectInspector);
if (localWork != null) {
for (Operator<? extends OperatorDesc> dummyOp : localWork.getDummyParentOp()) {
dummyOp.setExecContext(execContext);
dummyOp.initialize(jc, null);
}
}
} catch (Throwable e) {
abort = true;
if (e instanceof OutOfMemoryError) {
// Don't create a new object if we are already out of memory
throw (OutOfMemoryError) e;
} else {
throw new RuntimeException("Reduce operator initialization failed", e);
}
}
perfLogger.PerfLogEnd(CLASS_NAME, PerfLogger.SPARK_INIT_OPERATORS);
}