HBASE-15482 Provide an option to skip calculating block locations for SnapshotInputFormat

Signed-off-by: tedyu <yuzhihong@gmail.com>
This commit is contained in:
Xiang Li 2017-12-07 01:06:33 +08:00 committed by tedyu
parent 70608acf28
commit 5e7d16a3ce
4 changed files with 110 additions and 32 deletions

View File

@ -70,7 +70,7 @@ public class TableSnapshotInputFormatImpl {
// key for specifying the root dir of the restored snapshot
protected static final String RESTORE_DIR_KEY = "hbase.TableSnapshotInputFormat.restore.dir";
/** See {@link #getBestLocations(Configuration, HDFSBlocksDistribution)} */
/** See {@link #getBestLocations(Configuration, HDFSBlocksDistribution, int)} */
private static final String LOCALITY_CUTOFF_MULTIPLIER =
"hbase.tablesnapshotinputformat.locality.cutoff.multiplier";
private static final float DEFAULT_LOCALITY_CUTOFF_MULTIPLIER = 0.8f;
@ -86,6 +86,19 @@ public class TableSnapshotInputFormatImpl {
*/
public static final String NUM_SPLITS_PER_REGION = "hbase.mapreduce.splits.per.region";
/**
* Whether to calculate the block location for splits. Default to true.
* If the computing layer runs outside of HBase cluster, the block locality does not master.
* Setting this value to false could skip the calculation and save some time.
*
* Set access modifier to "public" so that these could be accessed by test classes of
* both org.apache.hadoop.hbase.mapred
* and org.apache.hadoop.hbase.mapreduce.
*/
public static final String SNAPSHOT_INPUTFORMAT_LOCALITY_ENABLED_KEY =
"hbase.TableSnapshotInputFormat.locality.enabled";
public static final boolean SNAPSHOT_INPUTFORMAT_LOCALITY_ENABLED_DEFAULT = true;
/**
* Implementation class for InputSplit logic common between mapred and mapreduce.
*/
@ -356,6 +369,9 @@ public class TableSnapshotInputFormatImpl {
Path tableDir = FSUtils.getTableDir(restoreDir, htd.getTableName());
boolean localityEnabled = conf.getBoolean(SNAPSHOT_INPUTFORMAT_LOCALITY_ENABLED_KEY,
SNAPSHOT_INPUTFORMAT_LOCALITY_ENABLED_DEFAULT);
List<InputSplit> splits = new ArrayList<>();
for (HRegionInfo hri : regionManifests) {
// load region descriptor
@ -365,36 +381,42 @@ public class TableSnapshotInputFormatImpl {
for (int i = 0; i < sp.length - 1; i++) {
if (PrivateCellUtil.overlappingKeys(scan.getStartRow(), scan.getStopRow(), sp[i],
sp[i + 1])) {
// compute HDFS locations from snapshot files (which will get the locations for
// referred hfiles)
List<String> hosts = getBestLocations(conf,
HRegion.computeHDFSBlocksDistribution(conf, htd, hri, tableDir));
List<String> hosts =
calculateLocationsForInputSplit(conf, htd, hri, tableDir, localityEnabled);
int len = Math.min(3, hosts.size());
hosts = hosts.subList(0, len);
Scan boundedScan = new Scan(scan);
boundedScan.setStartRow(sp[i]);
boundedScan.setStopRow(sp[i + 1]);
splits.add(new InputSplit(htd, hri, hosts, boundedScan, restoreDir));
}
}
} else {
if (PrivateCellUtil.overlappingKeys(scan.getStartRow(), scan.getStopRow(),
hri.getStartKey(), hri.getEndKey())) {
// compute HDFS locations from snapshot files (which will get the locations for
// referred hfiles)
List<String> hosts = getBestLocations(conf,
HRegion.computeHDFSBlocksDistribution(conf, htd, hri, tableDir));
int len = Math.min(3, hosts.size());
hosts = hosts.subList(0, len);
hri.getStartKey(), hri.getEndKey())) {
List<String> hosts =
calculateLocationsForInputSplit(conf, htd, hri, tableDir, localityEnabled);
splits.add(new InputSplit(htd, hri, hosts, scan, restoreDir));
}
}
}
return splits;
}
/**
* Compute block locations for snapshot files (which will get the locations for referred hfiles)
* only when localityEnabled is true.
*/
private static List<String> calculateLocationsForInputSplit(Configuration conf,
TableDescriptor htd, HRegionInfo hri, Path tableDir, boolean localityEnabled)
throws IOException {
if (localityEnabled) { // care block locality
return getBestLocations(conf,
HRegion.computeHDFSBlocksDistribution(conf, htd, hri, tableDir));
} else { // do not care block locality
return null;
}
}
/**
@ -408,30 +430,41 @@ public class TableSnapshotInputFormatImpl {
* we are doing a simple heuristic, where we will pass all hosts which have at least 80%
* (hbase.tablesnapshotinputformat.locality.cutoff.multiplier) as much block locality as the top
* host with the best locality.
* Return at most numTopsAtMost locations if there are more than that.
*/
public static List<String> getBestLocations(
Configuration conf, HDFSBlocksDistribution blockDistribution) {
List<String> locations = new ArrayList<>(3);
private static List<String> getBestLocations(Configuration conf,
HDFSBlocksDistribution blockDistribution, int numTopsAtMost) {
HostAndWeight[] hostAndWeights = blockDistribution.getTopHostsWithWeights();
if (hostAndWeights.length == 0) {
return locations;
if (hostAndWeights.length == 0) { // no matter what numTopsAtMost is
return null;
}
if (numTopsAtMost < 1) { // invalid if numTopsAtMost < 1, correct it to be 1
numTopsAtMost = 1;
}
int top = Math.min(numTopsAtMost, hostAndWeights.length);
List<String> locations = new ArrayList<>(top);
HostAndWeight topHost = hostAndWeights[0];
locations.add(topHost.getHost());
// Heuristic: filter all hosts which have at least cutoffMultiplier % of block locality
if (top == 1) { // only care about the top host
return locations;
}
// When top >= 2,
// do the heuristic: filter all hosts which have at least cutoffMultiplier % of block locality
double cutoffMultiplier
= conf.getFloat(LOCALITY_CUTOFF_MULTIPLIER, DEFAULT_LOCALITY_CUTOFF_MULTIPLIER);
double filterWeight = topHost.getWeight() * cutoffMultiplier;
for (int i = 1; i < hostAndWeights.length; i++) {
for (int i = 1; i <= top - 1; i++) {
if (hostAndWeights[i].getWeight() >= filterWeight) {
locations.add(hostAndWeights[i].getHost());
} else {
// As hostAndWeights is in descending order,
// we could break the loop as long as we meet a weight which is less than filterWeight.
break;
}
}
@ -439,6 +472,12 @@ public class TableSnapshotInputFormatImpl {
return locations;
}
public static List<String> getBestLocations(Configuration conf,
HDFSBlocksDistribution blockDistribution) {
// 3 nodes will contain highly local blocks. So default to 3.
return getBestLocations(conf, blockDistribution, 3);
}
private static String getSnapshotName(Configuration conf) {
String snapshotName = conf.get(SNAPSHOT_NAME_KEY);
if (snapshotName == null) {

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@ -18,6 +18,7 @@
package org.apache.hadoop.hbase.mapred;
import static org.apache.hadoop.hbase.mapreduce.TableSnapshotInputFormatImpl.SNAPSHOT_INPUTFORMAT_LOCALITY_ENABLED_DEFAULT;
import static org.mockito.Mockito.mock;
import org.apache.hadoop.fs.Path;
@ -138,7 +139,10 @@ public class TestTableSnapshotInputFormat extends TableSnapshotInputFormatTestBa
@Test
@Override
public void testWithMockedMapReduceMultiRegion() throws Exception {
testWithMockedMapReduce(UTIL, "testWithMockedMapReduceMultiRegion", 10, 1, 10);
testWithMockedMapReduce(
UTIL, "testWithMockedMapReduceMultiRegion", 10, 1, 10, true);
// It does not matter whether true or false is given to setLocalityEnabledTo,
// because it is not read in testWithMockedMapReduce().
}
@Test
@ -165,7 +169,8 @@ public class TestTableSnapshotInputFormat extends TableSnapshotInputFormatTestBa
@Override
protected void testWithMockedMapReduce(HBaseTestingUtility util, String snapshotName,
int numRegions, int numSplitsPerRegion, int expectedNumSplits) throws Exception {
int numRegions, int numSplitsPerRegion, int expectedNumSplits, boolean setLocalityEnabledTo)
throws Exception {
setupCluster();
final TableName tableName = TableName.valueOf(name.getMethodName());
try {
@ -173,6 +178,9 @@ public class TestTableSnapshotInputFormat extends TableSnapshotInputFormatTestBa
util, tableName, snapshotName, getStartRow(), getEndRow(), numRegions);
JobConf job = new JobConf(util.getConfiguration());
// setLocalityEnabledTo is ignored no matter what is specified, so as to test the case that
// SNAPSHOT_INPUTFORMAT_LOCALITY_ENABLED_KEY is not explicitly specified
// and the default value is taken.
Path tmpTableDir = util.getDataTestDirOnTestFS(snapshotName);
if (numSplitsPerRegion > 1) {
@ -206,10 +214,25 @@ public class TestTableSnapshotInputFormat extends TableSnapshotInputFormatTestBa
HBaseTestingUtility.SeenRowTracker rowTracker =
new HBaseTestingUtility.SeenRowTracker(startRow, stopRow);
// SNAPSHOT_INPUTFORMAT_LOCALITY_ENABLED_KEY is not explicitly specified,
// so the default value is taken.
boolean localityEnabled = SNAPSHOT_INPUTFORMAT_LOCALITY_ENABLED_DEFAULT;
for (int i = 0; i < splits.length; i++) {
// validate input split
InputSplit split = splits[i];
Assert.assertTrue(split instanceof TableSnapshotInputFormat.TableSnapshotRegionSplit);
if (localityEnabled) {
// When localityEnabled is true, meant to verify split.getLocations()
// by the following statement:
// Assert.assertTrue(split.getLocations() != null && split.getLocations().length != 0);
// However, getLocations() of some splits could return an empty array (length is 0),
// so drop the verification on length.
// TODO: investigate how to verify split.getLocations() when localityEnabled is true
Assert.assertTrue(split.getLocations() != null);
} else {
Assert.assertTrue(split.getLocations() != null && split.getLocations().length == 0);
}
// validate record reader
OutputCollector collector = mock(OutputCollector.class);

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@ -78,7 +78,8 @@ public abstract class TableSnapshotInputFormatTestBase {
}
protected abstract void testWithMockedMapReduce(HBaseTestingUtility util, String snapshotName,
int numRegions, int numSplitsPerRegion, int expectedNumSplits) throws Exception;
int numRegions, int numSplitsPerRegion, int expectedNumSplits, boolean setLocalityEnabledTo)
throws Exception;
protected abstract void testWithMapReduceImpl(HBaseTestingUtility util, TableName tableName,
String snapshotName, Path tableDir, int numRegions, int numSplitsPerRegion, int expectedNumSplits,
@ -90,12 +91,12 @@ public abstract class TableSnapshotInputFormatTestBase {
@Test
public void testWithMockedMapReduceSingleRegion() throws Exception {
testWithMockedMapReduce(UTIL, "testWithMockedMapReduceSingleRegion", 1, 1, 1);
testWithMockedMapReduce(UTIL, "testWithMockedMapReduceSingleRegion", 1, 1, 1, true);
}
@Test
public void testWithMockedMapReduceMultiRegion() throws Exception {
testWithMockedMapReduce(UTIL, "testWithMockedMapReduceMultiRegion", 10, 1, 8);
testWithMockedMapReduce(UTIL, "testWithMockedMapReduceMultiRegion", 10, 1, 8, false);
}
@Test

View File

@ -18,6 +18,9 @@
package org.apache.hadoop.hbase.mapreduce;
import static org.apache.hadoop.hbase.mapreduce.TableSnapshotInputFormatImpl.SNAPSHOT_INPUTFORMAT_LOCALITY_ENABLED_DEFAULT;
import static org.apache.hadoop.hbase.mapreduce.TableSnapshotInputFormatImpl.SNAPSHOT_INPUTFORMAT_LOCALITY_ENABLED_KEY;
import static org.mockito.Mockito.mock;
import static org.mockito.Mockito.when;
@ -98,7 +101,7 @@ public class TestTableSnapshotInputFormat extends TableSnapshotInputFormatTestBa
Configuration conf = UTIL.getConfiguration();
HDFSBlocksDistribution blockDistribution = new HDFSBlocksDistribution();
Assert.assertEquals(Lists.newArrayList(),
Assert.assertEquals(null,
TableSnapshotInputFormatImpl.getBestLocations(conf, blockDistribution));
blockDistribution.addHostsAndBlockWeight(new String[] {"h1"}, 1);
@ -132,7 +135,7 @@ public class TestTableSnapshotInputFormat extends TableSnapshotInputFormatTestBa
blockDistribution.addHostsAndBlockWeight(new String[] {"h3"}, 6);
blockDistribution.addHostsAndBlockWeight(new String[] {"h4"}, 9);
Assert.assertEquals(Lists.newArrayList("h2", "h3", "h4", "h1"),
Assert.assertEquals(Lists.newArrayList("h2", "h3", "h4"),
TableSnapshotInputFormatImpl.getBestLocations(conf, blockDistribution));
}
@ -210,14 +213,17 @@ public class TestTableSnapshotInputFormat extends TableSnapshotInputFormatTestBa
@Override
public void testWithMockedMapReduce(HBaseTestingUtility util, String snapshotName,
int numRegions, int numSplitsPerRegion, int expectedNumSplits) throws Exception {
int numRegions, int numSplitsPerRegion, int expectedNumSplits, boolean setLocalityEnabledTo)
throws Exception {
setupCluster();
final TableName tableName = TableName.valueOf(name.getMethodName());
try {
createTableAndSnapshot(
util, tableName, snapshotName, getStartRow(), getEndRow(), numRegions);
Job job = new Job(util.getConfiguration());
Configuration conf = util.getConfiguration();
conf.setBoolean(SNAPSHOT_INPUTFORMAT_LOCALITY_ENABLED_KEY, setLocalityEnabledTo);
Job job = new Job(conf);
Path tmpTableDir = util.getDataTestDirOnTestFS(snapshotName);
Scan scan = new Scan(getStartRow(), getEndRow()); // limit the scan
@ -304,10 +310,19 @@ public class TestTableSnapshotInputFormat extends TableSnapshotInputFormatTestBa
HBaseTestingUtility.SeenRowTracker rowTracker =
new HBaseTestingUtility.SeenRowTracker(startRow, stopRow);
boolean localityEnabled =
job.getConfiguration().getBoolean(SNAPSHOT_INPUTFORMAT_LOCALITY_ENABLED_KEY,
SNAPSHOT_INPUTFORMAT_LOCALITY_ENABLED_DEFAULT);
for (int i = 0; i < splits.size(); i++) {
// validate input split
InputSplit split = splits.get(i);
Assert.assertTrue(split instanceof TableSnapshotRegionSplit);
if (localityEnabled) {
Assert.assertTrue(split.getLocations() != null && split.getLocations().length != 0);
} else {
Assert.assertTrue(split.getLocations() != null && split.getLocations().length == 0);
}
// validate record reader
TaskAttemptContext taskAttemptContext = mock(TaskAttemptContext.class);