HBASE-19980 NullPointerException when restoring a snapshot after splitting a region

Signed-off-by: tedyu <yuzhihong@gmail.com>
This commit is contained in:
Toshihiro Suzuki 2018-02-14 19:55:59 +09:00 committed by tedyu
parent 8a3b4cdc67
commit 9cbf936f90
2 changed files with 73 additions and 36 deletions

View File

@ -195,11 +195,33 @@ public class RestoreSnapshotHelper {
// this instance, by removing the regions already present in the restore dir.
Set<String> regionNames = new HashSet<>(regionManifests.keySet());
List<RegionInfo> tableRegions = getTableRegions();
RegionInfo mobRegion = MobUtils.getMobRegionInfo(snapshotManifest.getTableDescriptor()
.getTableName());
if (tableRegions != null) {
// restore the mob region in case
if (regionNames.contains(mobRegion.getEncodedName())) {
monitor.rethrowException();
status.setStatus("Restoring mob region...");
List<RegionInfo> mobRegions = new ArrayList<>(1);
mobRegions.add(mobRegion);
restoreHdfsMobRegions(exec, regionManifests, mobRegions);
regionNames.remove(mobRegion.getEncodedName());
status.setStatus("Finished restoring mob region.");
}
}
if (regionNames.contains(mobRegion.getEncodedName())) {
// add the mob region
monitor.rethrowException();
status.setStatus("Cloning mob region...");
cloneHdfsMobRegion(regionManifests, mobRegion);
regionNames.remove(mobRegion.getEncodedName());
status.setStatus("Finished cloning mob region.");
}
// Identify which region are still available and which not.
// NOTE: we rely upon the region name as: "table name, start key, end key"
List<RegionInfo> tableRegions = getTableRegions();
if (tableRegions != null) {
monitor.rethrowException();
for (RegionInfo regionInfo: tableRegions) {
@ -213,50 +235,40 @@ public class RestoreSnapshotHelper {
metaChanges.addRegionToRemove(regionInfo);
}
}
// Restore regions using the snapshot data
monitor.rethrowException();
status.setStatus("Restoring table regions...");
if (regionNames.contains(mobRegion.getEncodedName())) {
// restore the mob region in case
List<RegionInfo> mobRegions = new ArrayList<>(1);
mobRegions.add(mobRegion);
restoreHdfsMobRegions(exec, regionManifests, mobRegions);
regionNames.remove(mobRegion.getEncodedName());
}
restoreHdfsRegions(exec, regionManifests, metaChanges.getRegionsToRestore());
status.setStatus("Finished restoring all table regions.");
// Remove regions from the current table
monitor.rethrowException();
status.setStatus("Starting to delete excess regions from table");
removeHdfsRegions(exec, metaChanges.getRegionsToRemove());
status.setStatus("Finished deleting excess regions from table.");
}
// Regions to Add: present in the snapshot but not in the current table
List<RegionInfo> regionsToAdd = new ArrayList<>(regionNames.size());
if (regionNames.size() > 0) {
List<RegionInfo> regionsToAdd = new ArrayList<>(regionNames.size());
monitor.rethrowException();
// add the mob region
if (regionNames.contains(mobRegion.getEncodedName())) {
cloneHdfsMobRegion(regionManifests, mobRegion);
regionNames.remove(mobRegion.getEncodedName());
}
for (String regionName: regionNames) {
LOG.info("region to add: " + regionName);
regionsToAdd.add(ProtobufUtil.toRegionInfo(regionManifests.get(regionName).getRegionInfo()));
regionsToAdd.add(ProtobufUtil.toRegionInfo(regionManifests.get(regionName)
.getRegionInfo()));
}
// Create new regions cloning from the snapshot
monitor.rethrowException();
status.setStatus("Cloning regions...");
RegionInfo[] clonedRegions = cloneHdfsRegions(exec, regionManifests, regionsToAdd);
metaChanges.setNewRegions(clonedRegions);
status.setStatus("Finished cloning regions.");
}
// Create new regions cloning from the snapshot
// HBASE-19980: We need to call cloneHdfsRegions() before restoreHdfsRegions() because
// regionsMap is constructed in cloneHdfsRegions() and it can be used in restoreHdfsRegions().
monitor.rethrowException();
status.setStatus("Cloning regions...");
RegionInfo[] clonedRegions = cloneHdfsRegions(exec, regionManifests, regionsToAdd);
metaChanges.setNewRegions(clonedRegions);
status.setStatus("Finished cloning regions.");
// Restore regions using the snapshot data
monitor.rethrowException();
status.setStatus("Restoring table regions...");
restoreHdfsRegions(exec, regionManifests, metaChanges.getRegionsToRestore());
status.setStatus("Finished restoring all table regions.");
// Remove regions from the current table
monitor.rethrowException();
status.setStatus("Starting to delete excess regions from table");
removeHdfsRegions(exec, metaChanges.getRegionsToRemove());
status.setStatus("Finished deleting excess regions from table.");
LOG.info("finishing restore table regions using snapshot=" + snapshotDesc);
return metaChanges;
@ -742,11 +754,16 @@ public class RestoreSnapshotHelper {
// Add the daughter region to the map
String regionName = Bytes.toString(regionsMap.get(regionInfo.getEncodedNameAsBytes()));
if (regionName == null) {
regionName = regionInfo.getEncodedName();
}
LOG.debug("Restore reference " + regionName + " to " + clonedRegionName);
synchronized (parentsMap) {
Pair<String, String> daughters = parentsMap.get(clonedRegionName);
if (daughters == null) {
daughters = new Pair<>(regionName, null);
// In case one side of the split is already compacted, regionName is put as both first and
// second of Pair
daughters = new Pair<>(regionName, regionName);
parentsMap.put(clonedRegionName, daughters);
} else if (!regionName.equals(daughters.getFirst())) {
daughters.setSecond(regionName);

View File

@ -23,6 +23,7 @@ import static org.junit.Assert.fail;
import java.io.IOException;
import java.util.HashSet;
import java.util.List;
import java.util.Set;
import org.apache.hadoop.conf.Configuration;
@ -295,6 +296,25 @@ public class TestRestoreSnapshotFromClient {
}
}
@Test
public void testRestoreSnapshotAfterSplittingRegions() throws IOException, InterruptedException {
List<RegionInfo> regionInfos = admin.getRegions(tableName);
RegionReplicaUtil.removeNonDefaultRegions(regionInfos);
// Split the first region
splitRegion(regionInfos.get(0));
// Take a snapshot
admin.snapshot(snapshotName1, tableName);
// Restore the snapshot
admin.disableTable(tableName);
admin.restoreSnapshot(snapshotName1);
admin.enableTable(tableName);
verifyRowCount(TEST_UTIL, tableName, snapshot1Rows);
}
// ==========================================================================
// Helpers
// ==========================================================================