/**
* Get the HRegionInfo from cache, if not there, from the hbase:meta table. Be careful. Does RPC.
* Do not hold a lock or synchronize when you call this method.
*
* @param regionName
* @return HRegionInfo for the region
*/
@SuppressWarnings("deprecation")
protected HRegionInfo getRegionInfo(final byte[] regionName) {
String encodedName = HRegionInfo.encodeRegionName(regionName);
RegionState regionState = getRegionState(encodedName);
if (regionState != null) {
return regionState.getRegion();
}
try {
Pair<HRegionInfo, ServerName> p =
MetaTableAccessor.getRegion(server.getConnection(), regionName);
HRegionInfo hri = p == null ? null : p.getFirst();
if (hri != null) {
createRegionState(hri);
}
return hri;
} catch (IOException e) {
server.abort(
"Aborting because error occoured while reading "
+ Bytes.toStringBinary(regionName)
+ " from hbase:meta",
e);
return null;
}
}
/**
* A table is deleted. Remove its regions from all internal maps. We loop through all regions
* assuming we don't delete tables too much.
*/
public void tableDeleted(final TableName tableName) {
Set<HRegionInfo> regionsToDelete = new HashSet<HRegionInfo>();
synchronized (this) {
for (RegionState state : regionStates.values()) {
HRegionInfo region = state.getRegion();
if (region.getTable().equals(tableName)) {
regionsToDelete.add(region);
}
}
}
for (HRegionInfo region : regionsToDelete) {
deleteRegion(region);
}
}
/**
* Gets current state of all regions of the table. This method looks at the in-memory state. It
* does not go to <code>hbase:meta</code>. Method guaranteed to return keys for all states in
* {@link org.apache.hadoop.hbase.master.RegionState.State}
*
* @param tableName
* @return Online regions from <code>tableName</code>
*/
public synchronized Map<RegionState.State, List<HRegionInfo>> getRegionByStateOfTable(
TableName tableName) {
Map<RegionState.State, List<HRegionInfo>> tableRegions =
new HashMap<State, List<HRegionInfo>>();
for (State state : State.values()) {
tableRegions.put(state, new ArrayList<HRegionInfo>());
}
Map<String, RegionState> indexMap = regionStatesTableIndex.get(tableName);
if (indexMap == null) return tableRegions;
for (RegionState regionState : indexMap.values()) {
tableRegions.get(regionState.getState()).add(regionState.getRegion());
}
return tableRegions;
}
/**
* A region is offline, won't be in transition any more. Its state should be the specified
* expected state, which can only be Split/Merged/Offline/null(=Offline)/SplittingNew/MergingNew.
*/
public void regionOffline(final HRegionInfo hri, final State expectedState) {
Preconditions.checkArgument(
expectedState == null || RegionState.isUnassignable(expectedState),
"Offlined region should not be " + expectedState);
if (isRegionInState(hri, State.SPLITTING_NEW, State.MERGING_NEW)) {
// Remove it from all region maps
deleteRegion(hri);
return;
}
State newState = expectedState == null ? State.OFFLINE : expectedState;
updateRegionState(hri, newState);
String encodedName = hri.getEncodedName();
synchronized (this) {
regionsInTransition.remove(encodedName);
ServerName oldServerName = regionAssignments.remove(hri);
if (oldServerName != null && serverHoldings.containsKey(oldServerName)) {
if (newState == State.MERGED
|| newState == State.SPLIT
|| hri.isMetaRegion()
|| tableStateManager.isTableState(
hri.getTable(), TableState.State.DISABLED, TableState.State.DISABLING)) {
// Offline the region only if it's merged/split, or the table is disabled/disabling.
// Otherwise, offline it from this server only when it is online on a different server.
LOG.info("Offlined " + hri.getShortNameToLog() + " from " + oldServerName);
removeFromServerHoldings(oldServerName, hri);
removeFromReplicaMapping(hri);
} else {
// Need to remember it so that we can offline it from this
// server when it is online on a different server.
oldAssignments.put(encodedName, oldServerName);
}
}
}
}
static boolean isOneOfStates(RegionState regionState, State... states) {
State s = regionState != null ? regionState.getState() : null;
for (State state : states) {
if (s == state) return true;
}
return false;
}
/**
* At cluster clean re/start, mark all user regions closed except those of tables that are
* excluded, such as disabled/disabling/enabling tables. All user regions and their previous
* locations are returned.
*/
synchronized Map<HRegionInfo, ServerName> closeAllUserRegions(Set<TableName> excludedTables) {
boolean noExcludeTables = excludedTables == null || excludedTables.isEmpty();
Set<HRegionInfo> toBeClosed = new HashSet<HRegionInfo>(regionStates.size());
for (RegionState state : regionStates.values()) {
HRegionInfo hri = state.getRegion();
if (state.isSplit() || hri.isSplit()) {
continue;
}
TableName tableName = hri.getTable();
if (!TableName.META_TABLE_NAME.equals(tableName)
&& (noExcludeTables || !excludedTables.contains(tableName))) {
toBeClosed.add(hri);
}
}
Map<HRegionInfo, ServerName> allUserRegions =
new HashMap<HRegionInfo, ServerName>(toBeClosed.size());
for (HRegionInfo hri : toBeClosed) {
RegionState regionState = updateRegionState(hri, State.CLOSED);
allUserRegions.put(hri, regionState.getServerName());
}
return allUserRegions;
}
private RegionState putRegionState(RegionState regionState) {
HRegionInfo hri = regionState.getRegion();
String encodedName = hri.getEncodedName();
TableName table = hri.getTable();
RegionState oldState = regionStates.put(encodedName, regionState);
Map<String, RegionState> map = regionStatesTableIndex.get(table);
if (map == null) {
map = new HashMap<String, RegionState>();
regionStatesTableIndex.put(table, map);
}
map.put(encodedName, regionState);
return oldState;
}
@Override
public int compare(RegionState l, RegionState r) {
return Long.compare(l.getStamp(), r.getStamp());
}
/** A server is offline, all regions on it are dead. */
public List<HRegionInfo> serverOffline(final ServerName sn) {
// Offline all regions on this server not already in transition.
List<HRegionInfo> rits = new ArrayList<HRegionInfo>();
Set<HRegionInfo> regionsToCleanIfNoMetaEntry = new HashSet<HRegionInfo>();
// Offline regions outside the loop and synchronized block to avoid
// ConcurrentModificationException and deadlock in case of meta anassigned,
// but RegionState a blocked.
Set<HRegionInfo> regionsToOffline = new HashSet<HRegionInfo>();
synchronized (this) {
Set<HRegionInfo> assignedRegions = serverHoldings.get(sn);
if (assignedRegions == null) {
assignedRegions = new HashSet<HRegionInfo>();
}
for (HRegionInfo region : assignedRegions) {
// Offline open regions, no need to offline if SPLIT/MERGED/OFFLINE
if (isRegionOnline(region)) {
regionsToOffline.add(region);
} else if (isRegionInState(region, State.SPLITTING, State.MERGING)) {
LOG.debug("Offline splitting/merging region " + getRegionState(region));
regionsToOffline.add(region);
}
}
for (RegionState state : regionsInTransition.values()) {
HRegionInfo hri = state.getRegion();
if (assignedRegions.contains(hri)) {
// Region is open on this region server, but in transition.
// This region must be moving away from this server, or splitting/merging.
// SSH will handle it, either skip assigning, or re-assign.
LOG.info("Transitioning " + state + " will be handled by ServerCrashProcedure for " + sn);
} else if (sn.equals(state.getServerName())) {
// Region is in transition on this region server, and this
// region is not open on this server. So the region must be
// moving to this server from another one (i.e. opening or
// pending open on this server, was open on another one.
// Offline state is also kind of pending open if the region is in
// transition. The region could be in failed_close state too if we have
// tried several times to open it while this region server is not reachable)
if (isOneOfStates(
state,
State.OPENING,
State.PENDING_OPEN,
State.FAILED_OPEN,
State.FAILED_CLOSE,
State.OFFLINE)) {
LOG.info(
"Found region in " + state + " to be reassigned by ServerCrashProcedure for " + sn);
rits.add(hri);
} else if (isOneOfStates(state, State.SPLITTING_NEW)) {
regionsToCleanIfNoMetaEntry.add(state.getRegion());
} else {
LOG.warn("THIS SHOULD NOT HAPPEN: unexpected " + state);
}
}
}
this.notifyAll();
}
for (HRegionInfo hri : regionsToOffline) {
regionOffline(hri);
}
cleanIfNoMetaEntry(regionsToCleanIfNoMetaEntry);
return rits;
}
/** Update a region state. It will be put in transition if not already there. */
public RegionState updateRegionState(final HRegionInfo hri, final State state) {
RegionState regionState = getRegionState(hri.getEncodedName());
return updateRegionState(hri, state, regionState == null ? null : regionState.getServerName());
}
/** @return True if hbase:meta table region is in transition. */
public synchronized boolean isMetaRegionInTransition() {
for (RegionState state : regionsInTransition.values()) {
if (state.getRegion().isMetaRegion()) return true;
}
return false;
}
/** Update a region state. It will be put in transition if not already there. */
private RegionState updateRegionState(
final HRegionInfo hri,
final RegionState.State state,
final ServerName serverName,
long openSeqNum) {
if (state == RegionState.State.FAILED_CLOSE || state == RegionState.State.FAILED_OPEN) {
LOG.warn(
"Failed to open/close "
+ hri.getShortNameToLog()
+ " on "
+ serverName
+ ", set to "
+ state);
}
String encodedName = hri.getEncodedName();
RegionState regionState = new RegionState(hri, state, System.currentTimeMillis(), serverName);
RegionState oldState = getRegionState(encodedName);
if (!regionState.equals(oldState)) {
LOG.info("Transition " + oldState + " to " + regionState);
// Persist region state before updating in-memory info, if needed
regionStateStore.updateRegionState(openSeqNum, regionState, oldState);
}
synchronized (this) {
regionsInTransition.put(encodedName, regionState);
putRegionState(regionState);
// For these states, region should be properly closed.
// There should be no log splitting issue.
if ((state == State.CLOSED || state == State.MERGED || state == State.SPLIT)
&& lastAssignments.containsKey(encodedName)) {
ServerName last = lastAssignments.get(encodedName);
if (last.equals(serverName)) {
lastAssignments.remove(encodedName);
} else {
LOG.warn(encodedName + " moved to " + state + " on " + serverName + ", expected " + last);
}
}
// Once a region is opened, record its last assignment right away.
if (serverName != null && state == State.OPEN) {
ServerName last = lastAssignments.get(encodedName);
if (!serverName.equals(last)) {
lastAssignments.put(encodedName, serverName);
if (last != null && isServerDeadAndNotProcessed(last)) {
LOG.warn(
encodedName
+ " moved to "
+ serverName
+ ", while it's previous host "
+ last
+ " is dead but not processed yet");
}
}
}
// notify the change
this.notifyAll();
}
return regionState;
}