/**
* Update the assignment plan to all the region servers
*
* @param plan
* @throws IOException
*/
private void updateAssignmentPlanToRegionServers(FavoredNodesPlan plan) throws IOException {
LOG.info("Start to update the region servers with the new assignment plan");
// Get the region to region server map
Map<ServerName, List<HRegionInfo>> currentAssignment =
this.getRegionAssignmentSnapshot().getRegionServerToRegionMap();
// track of the failed and succeeded updates
int succeededNum = 0;
Map<ServerName, Exception> failedUpdateMap = new HashMap<ServerName, Exception>();
for (Map.Entry<ServerName, List<HRegionInfo>> entry : currentAssignment.entrySet()) {
List<Pair<HRegionInfo, List<ServerName>>> regionUpdateInfos =
new ArrayList<Pair<HRegionInfo, List<ServerName>>>();
try {
// Keep track of the favored updates for the current region server
FavoredNodesPlan singleServerPlan = null;
// Find out all the updates for the current region server
for (HRegionInfo region : entry.getValue()) {
List<ServerName> favoredServerList = plan.getFavoredNodes(region);
if (favoredServerList != null
&& favoredServerList.size() == FavoredNodeAssignmentHelper.FAVORED_NODES_NUM) {
// Create the single server plan if necessary
if (singleServerPlan == null) {
singleServerPlan = new FavoredNodesPlan();
}
// Update the single server update
singleServerPlan.updateAssignmentPlan(region, favoredServerList);
regionUpdateInfos.add(
new Pair<HRegionInfo, List<ServerName>>(region, favoredServerList));
}
}
if (singleServerPlan != null) {
// Update the current region server with its updated favored nodes
BlockingInterface currentRegionServer =
((ClusterConnection) this.connection).getAdmin(entry.getKey());
UpdateFavoredNodesRequest request =
RequestConverter.buildUpdateFavoredNodesRequest(regionUpdateInfos);
UpdateFavoredNodesResponse updateFavoredNodesResponse =
currentRegionServer.updateFavoredNodes(null, request);
LOG.info(
"Region server "
+ ProtobufUtil.getServerInfo(null, currentRegionServer).getServerName()
+ " has updated "
+ updateFavoredNodesResponse.getResponse()
+ " / "
+ singleServerPlan.getAssignmentMap().size()
+ " regions with the assignment plan");
succeededNum++;
}
} catch (Exception e) {
failedUpdateMap.put(entry.getKey(), e);
}
}
// log the succeeded updates
LOG.info("Updated " + succeededNum + " region servers with " + "the new assignment plan");
// log the failed updates
int failedNum = failedUpdateMap.size();
if (failedNum != 0) {
LOG.error(
"Failed to update the following + "
+ failedNum
+ " region servers with its corresponding favored nodes");
for (Map.Entry<ServerName, Exception> entry : failedUpdateMap.entrySet()) {
LOG.error(
"Failed to update "
+ entry.getKey().getHostAndPort()
+ " because of "
+ entry.getValue().getMessage());
}
}
}
public static void main(String args[]) throws IOException {
Options opt = new Options();
opt.addOption("w", "write", false, "write the assignments to hbase:meta only");
opt.addOption(
"u", "update", false, "update the assignments to hbase:meta and RegionServers together");
opt.addOption("n", "dry-run", false, "do not write assignments to META");
opt.addOption("v", "verify", false, "verify current assignments against META");
opt.addOption("p", "print", false, "print the current assignment plan in META");
opt.addOption("h", "help", false, "print usage");
opt.addOption("d", "verification-details", false, "print the details of verification report");
opt.addOption("zk", true, "to set the zookeeper quorum");
opt.addOption("fs", true, "to set HDFS");
opt.addOption("hbase_root", true, "to set hbase_root directory");
opt.addOption(
"overwrite",
false,
"overwrite the favored nodes for a single region,"
+ "for example: -update -r regionName -f server1:port,server2:port,server3:port");
opt.addOption("r", true, "The region name that needs to be updated");
opt.addOption("f", true, "The new favored nodes");
opt.addOption(
"tables",
true,
"The list of table names splitted by ',' ;" + "For example: -tables: t1,t2,...,tn");
opt.addOption("l", "locality", true, "enforce the maxium locality");
opt.addOption("m", "min-move", true, "enforce minium assignment move");
opt.addOption("diff", false, "calculate difference between assignment plans");
opt.addOption("munkres", false, "use munkres to place secondaries and tertiaries");
opt.addOption(
"ld",
"locality-dispersion",
false,
"print locality and dispersion " + "information for current plan");
try {
// Set the log4j
Logger.getLogger("org.apache.zookeeper").setLevel(Level.ERROR);
Logger.getLogger("org.apache.hadoop.hbase").setLevel(Level.ERROR);
Logger.getLogger("org.apache.hadoop.hbase.master.RegionPlacementMaintainer")
.setLevel(Level.INFO);
CommandLine cmd = new GnuParser().parse(opt, args);
Configuration conf = HBaseConfiguration.create();
boolean enforceMinAssignmentMove = true;
boolean enforceLocality = true;
boolean verificationDetails = false;
// Read all the options
if ((cmd.hasOption("l") && cmd.getOptionValue("l").equalsIgnoreCase("false"))
|| (cmd.hasOption("locality")
&& cmd.getOptionValue("locality").equalsIgnoreCase("false"))) {
enforceLocality = false;
}
if ((cmd.hasOption("m") && cmd.getOptionValue("m").equalsIgnoreCase("false"))
|| (cmd.hasOption("min-move")
&& cmd.getOptionValue("min-move").equalsIgnoreCase("false"))) {
enforceMinAssignmentMove = false;
}
if (cmd.hasOption("zk")) {
conf.set(HConstants.ZOOKEEPER_QUORUM, cmd.getOptionValue("zk"));
LOG.info("Setting the zk quorum: " + conf.get(HConstants.ZOOKEEPER_QUORUM));
}
if (cmd.hasOption("fs")) {
conf.set(FileSystem.FS_DEFAULT_NAME_KEY, cmd.getOptionValue("fs"));
LOG.info("Setting the HDFS: " + conf.get(FileSystem.FS_DEFAULT_NAME_KEY));
}
if (cmd.hasOption("hbase_root")) {
conf.set(HConstants.HBASE_DIR, cmd.getOptionValue("hbase_root"));
LOG.info("Setting the hbase root directory: " + conf.get(HConstants.HBASE_DIR));
}
// Create the region placement obj
RegionPlacementMaintainer rp =
new RegionPlacementMaintainer(conf, enforceLocality, enforceMinAssignmentMove);
if (cmd.hasOption("d") || cmd.hasOption("verification-details")) {
verificationDetails = true;
}
if (cmd.hasOption("tables")) {
String tableNameListStr = cmd.getOptionValue("tables");
String[] tableNames = StringUtils.split(tableNameListStr, ",");
rp.setTargetTableName(tableNames);
}
if (cmd.hasOption("munkres")) {
USE_MUNKRES_FOR_PLACING_SECONDARY_AND_TERTIARY = true;
}
// Read all the modes
if (cmd.hasOption("v") || cmd.hasOption("verify")) {
// Verify the region placement.
rp.verifyRegionPlacement(verificationDetails);
} else if (cmd.hasOption("n") || cmd.hasOption("dry-run")) {
// Generate the assignment plan only without updating the hbase:meta and RS
FavoredNodesPlan plan = rp.getNewAssignmentPlan();
printAssignmentPlan(plan);
} else if (cmd.hasOption("w") || cmd.hasOption("write")) {
// Generate the new assignment plan
FavoredNodesPlan plan = rp.getNewAssignmentPlan();
// Print the new assignment plan
printAssignmentPlan(plan);
// Write the new assignment plan to META
rp.updateAssignmentPlanToMeta(plan);
} else if (cmd.hasOption("u") || cmd.hasOption("update")) {
// Generate the new assignment plan
FavoredNodesPlan plan = rp.getNewAssignmentPlan();
// Print the new assignment plan
printAssignmentPlan(plan);
// Update the assignment to hbase:meta and Region Servers
rp.updateAssignmentPlan(plan);
} else if (cmd.hasOption("diff")) {
FavoredNodesPlan newPlan = rp.getNewAssignmentPlan();
Map<String, Map<String, Float>> locality =
FSUtils.getRegionDegreeLocalityMappingFromFS(conf);
Map<TableName, Integer> movesPerTable = rp.getRegionsMovement(newPlan);
rp.checkDifferencesWithOldPlan(movesPerTable, locality, newPlan);
System.out.println("Do you want to update the assignment plan? [y/n]");
Scanner s = new Scanner(System.in);
String input = s.nextLine().trim();
if (input.equals("y")) {
System.out.println("Updating assignment plan...");
rp.updateAssignmentPlan(newPlan);
}
s.close();
} else if (cmd.hasOption("ld")) {
Map<String, Map<String, Float>> locality =
FSUtils.getRegionDegreeLocalityMappingFromFS(conf);
rp.printLocalityAndDispersionForCurrentPlan(locality);
} else if (cmd.hasOption("p") || cmd.hasOption("print")) {
FavoredNodesPlan plan = rp.getRegionAssignmentSnapshot().getExistingAssignmentPlan();
printAssignmentPlan(plan);
} else if (cmd.hasOption("overwrite")) {
if (!cmd.hasOption("f") || !cmd.hasOption("r")) {
throw new IllegalArgumentException(
"Please specify: "
+ " -update -r regionName -f server1:port,server2:port,server3:port");
}
String regionName = cmd.getOptionValue("r");
String favoredNodesStr = cmd.getOptionValue("f");
LOG.info(
"Going to update the region "
+ regionName
+ " with the new favored nodes "
+ favoredNodesStr);
List<ServerName> favoredNodes = null;
HRegionInfo regionInfo =
rp.getRegionAssignmentSnapshot().getRegionNameToRegionInfoMap().get(regionName);
if (regionInfo == null) {
LOG.error("Cannot find the region " + regionName + " from the META");
} else {
try {
favoredNodes = getFavoredNodeList(favoredNodesStr);
} catch (IllegalArgumentException e) {
LOG.error("Cannot parse the invalid favored nodes because " + e);
}
FavoredNodesPlan newPlan = new FavoredNodesPlan();
newPlan.updateAssignmentPlan(regionInfo, favoredNodes);
rp.updateAssignmentPlan(newPlan);
}
} else {
printHelp(opt);
}
} catch (ParseException e) {
printHelp(opt);
}
}
/**
* Generate the assignment plan for the existing table
*
* @param tableName
* @param assignmentSnapshot
* @param regionLocalityMap
* @param plan
* @param munkresForSecondaryAndTertiary if set on true the assignment plan for the tertiary and
* secondary will be generated with Munkres algorithm, otherwise will be generated using
* placeSecondaryAndTertiaryRS
* @throws IOException
*/
private void genAssignmentPlan(
TableName tableName,
SnapshotOfRegionAssignmentFromMeta assignmentSnapshot,
Map<String, Map<String, Float>> regionLocalityMap,
FavoredNodesPlan plan,
boolean munkresForSecondaryAndTertiary)
throws IOException {
// Get the all the regions for the current table
List<HRegionInfo> regions = assignmentSnapshot.getTableToRegionMap().get(tableName);
int numRegions = regions.size();
// Get the current assignment map
Map<HRegionInfo, ServerName> currentAssignmentMap =
assignmentSnapshot.getRegionToRegionServerMap();
// Get the all the region servers
List<ServerName> servers = new ArrayList<ServerName>();
try (Admin admin = this.connection.getAdmin()) {
servers.addAll(admin.getClusterStatus().getServers());
}
LOG.info(
"Start to generate assignment plan for "
+ numRegions
+ " regions from table "
+ tableName
+ " with "
+ servers.size()
+ " region servers");
int slotsPerServer = (int) Math.ceil((float) numRegions / servers.size());
int regionSlots = slotsPerServer * servers.size();
// Compute the primary, secondary and tertiary costs for each region/server
// pair. These costs are based only on node locality and rack locality, and
// will be modified later.
float[][] primaryCost = new float[numRegions][regionSlots];
float[][] secondaryCost = new float[numRegions][regionSlots];
float[][] tertiaryCost = new float[numRegions][regionSlots];
if (this.enforceLocality && regionLocalityMap != null) {
// Transform the locality mapping into a 2D array, assuming that any
// unspecified locality value is 0.
float[][] localityPerServer = new float[numRegions][regionSlots];
for (int i = 0; i < numRegions; i++) {
Map<String, Float> serverLocalityMap =
regionLocalityMap.get(regions.get(i).getEncodedName());
if (serverLocalityMap == null) {
continue;
}
for (int j = 0; j < servers.size(); j++) {
String serverName = servers.get(j).getHostname();
if (serverName == null) {
continue;
}
Float locality = serverLocalityMap.get(serverName);
if (locality == null) {
continue;
}
for (int k = 0; k < slotsPerServer; k++) {
// If we can't find the locality of a region to a server, which occurs
// because locality is only reported for servers which have some
// blocks of a region local, then the locality for that pair is 0.
localityPerServer[i][j * slotsPerServer + k] = locality.floatValue();
}
}
}
// Compute the total rack locality for each region in each rack. The total
// rack locality is the sum of the localities of a region on all servers in
// a rack.
Map<String, Map<HRegionInfo, Float>> rackRegionLocality =
new HashMap<String, Map<HRegionInfo, Float>>();
for (int i = 0; i < numRegions; i++) {
HRegionInfo region = regions.get(i);
for (int j = 0; j < regionSlots; j += slotsPerServer) {
String rack = rackManager.getRack(servers.get(j / slotsPerServer));
Map<HRegionInfo, Float> rackLocality = rackRegionLocality.get(rack);
if (rackLocality == null) {
rackLocality = new HashMap<HRegionInfo, Float>();
rackRegionLocality.put(rack, rackLocality);
}
Float localityObj = rackLocality.get(region);
float locality = localityObj == null ? 0 : localityObj.floatValue();
locality += localityPerServer[i][j];
rackLocality.put(region, locality);
}
}
for (int i = 0; i < numRegions; i++) {
for (int j = 0; j < regionSlots; j++) {
String rack = rackManager.getRack(servers.get(j / slotsPerServer));
Float totalRackLocalityObj = rackRegionLocality.get(rack).get(regions.get(i));
float totalRackLocality =
totalRackLocalityObj == null ? 0 : totalRackLocalityObj.floatValue();
// Primary cost aims to favor servers with high node locality and low
// rack locality, so that secondaries and tertiaries can be chosen for
// nodes with high rack locality. This might give primaries with
// slightly less locality at first compared to a cost which only
// considers the node locality, but should be better in the long run.
primaryCost[i][j] = 1 - (2 * localityPerServer[i][j] - totalRackLocality);
// Secondary cost aims to favor servers with high node locality and high
// rack locality since the tertiary will be chosen from the same rack as
// the secondary. This could be negative, but that is okay.
secondaryCost[i][j] = 2 - (localityPerServer[i][j] + totalRackLocality);
// Tertiary cost is only concerned with the node locality. It will later
// be restricted to only hosts on the same rack as the secondary.
tertiaryCost[i][j] = 1 - localityPerServer[i][j];
}
}
}
if (this.enforceMinAssignmentMove && currentAssignmentMap != null) {
// We want to minimize the number of regions which move as the result of a
// new assignment. Therefore, slightly penalize any placement which is for
// a host that is not currently serving the region.
for (int i = 0; i < numRegions; i++) {
for (int j = 0; j < servers.size(); j++) {
ServerName currentAddress = currentAssignmentMap.get(regions.get(i));
if (currentAddress != null && !currentAddress.equals(servers.get(j))) {
for (int k = 0; k < slotsPerServer; k++) {
primaryCost[i][j * slotsPerServer + k] += NOT_CURRENT_HOST_PENALTY;
}
}
}
}
}
// Artificially increase cost of last slot of each server to evenly
// distribute the slop, otherwise there will be a few servers with too few
// regions and many servers with the max number of regions.
for (int i = 0; i < numRegions; i++) {
for (int j = 0; j < regionSlots; j += slotsPerServer) {
primaryCost[i][j] += LAST_SLOT_COST_PENALTY;
secondaryCost[i][j] += LAST_SLOT_COST_PENALTY;
tertiaryCost[i][j] += LAST_SLOT_COST_PENALTY;
}
}
RandomizedMatrix randomizedMatrix = new RandomizedMatrix(numRegions, regionSlots);
primaryCost = randomizedMatrix.transform(primaryCost);
int[] primaryAssignment = new MunkresAssignment(primaryCost).solve();
primaryAssignment = randomizedMatrix.invertIndices(primaryAssignment);
// Modify the secondary and tertiary costs for each region/server pair to
// prevent a region from being assigned to the same rack for both primary
// and either one of secondary or tertiary.
for (int i = 0; i < numRegions; i++) {
int slot = primaryAssignment[i];
String rack = rackManager.getRack(servers.get(slot / slotsPerServer));
for (int k = 0; k < servers.size(); k++) {
if (!rackManager.getRack(servers.get(k)).equals(rack)) {
continue;
}
if (k == slot / slotsPerServer) {
// Same node, do not place secondary or tertiary here ever.
for (int m = 0; m < slotsPerServer; m++) {
secondaryCost[i][k * slotsPerServer + m] = MAX_COST;
tertiaryCost[i][k * slotsPerServer + m] = MAX_COST;
}
} else {
// Same rack, do not place secondary or tertiary here if possible.
for (int m = 0; m < slotsPerServer; m++) {
secondaryCost[i][k * slotsPerServer + m] = AVOID_COST;
tertiaryCost[i][k * slotsPerServer + m] = AVOID_COST;
}
}
}
}
if (munkresForSecondaryAndTertiary) {
randomizedMatrix = new RandomizedMatrix(numRegions, regionSlots);
secondaryCost = randomizedMatrix.transform(secondaryCost);
int[] secondaryAssignment = new MunkresAssignment(secondaryCost).solve();
secondaryAssignment = randomizedMatrix.invertIndices(secondaryAssignment);
// Modify the tertiary costs for each region/server pair to ensure that a
// region is assigned to a tertiary server on the same rack as its secondary
// server, but not the same server in that rack.
for (int i = 0; i < numRegions; i++) {
int slot = secondaryAssignment[i];
String rack = rackManager.getRack(servers.get(slot / slotsPerServer));
for (int k = 0; k < servers.size(); k++) {
if (k == slot / slotsPerServer) {
// Same node, do not place tertiary here ever.
for (int m = 0; m < slotsPerServer; m++) {
tertiaryCost[i][k * slotsPerServer + m] = MAX_COST;
}
} else {
if (rackManager.getRack(servers.get(k)).equals(rack)) {
continue;
}
// Different rack, do not place tertiary here if possible.
for (int m = 0; m < slotsPerServer; m++) {
tertiaryCost[i][k * slotsPerServer + m] = AVOID_COST;
}
}
}
}
randomizedMatrix = new RandomizedMatrix(numRegions, regionSlots);
tertiaryCost = randomizedMatrix.transform(tertiaryCost);
int[] tertiaryAssignment = new MunkresAssignment(tertiaryCost).solve();
tertiaryAssignment = randomizedMatrix.invertIndices(tertiaryAssignment);
for (int i = 0; i < numRegions; i++) {
List<ServerName> favoredServers =
new ArrayList<ServerName>(FavoredNodeAssignmentHelper.FAVORED_NODES_NUM);
ServerName s = servers.get(primaryAssignment[i] / slotsPerServer);
favoredServers.add(
ServerName.valueOf(s.getHostname(), s.getPort(), ServerName.NON_STARTCODE));
s = servers.get(secondaryAssignment[i] / slotsPerServer);
favoredServers.add(
ServerName.valueOf(s.getHostname(), s.getPort(), ServerName.NON_STARTCODE));
s = servers.get(tertiaryAssignment[i] / slotsPerServer);
favoredServers.add(
ServerName.valueOf(s.getHostname(), s.getPort(), ServerName.NON_STARTCODE));
// Update the assignment plan
plan.updateAssignmentPlan(regions.get(i), favoredServers);
}
LOG.info(
"Generated the assignment plan for "
+ numRegions
+ " regions from table "
+ tableName
+ " with "
+ servers.size()
+ " region servers");
LOG.info("Assignment plan for secondary and tertiary generated " + "using MunkresAssignment");
} else {
Map<HRegionInfo, ServerName> primaryRSMap = new HashMap<HRegionInfo, ServerName>();
for (int i = 0; i < numRegions; i++) {
primaryRSMap.put(regions.get(i), servers.get(primaryAssignment[i] / slotsPerServer));
}
FavoredNodeAssignmentHelper favoredNodeHelper =
new FavoredNodeAssignmentHelper(servers, conf);
favoredNodeHelper.initialize();
Map<HRegionInfo, ServerName[]> secondaryAndTertiaryMap =
favoredNodeHelper.placeSecondaryAndTertiaryWithRestrictions(primaryRSMap);
for (int i = 0; i < numRegions; i++) {
List<ServerName> favoredServers =
new ArrayList<ServerName>(FavoredNodeAssignmentHelper.FAVORED_NODES_NUM);
HRegionInfo currentRegion = regions.get(i);
ServerName s = primaryRSMap.get(currentRegion);
favoredServers.add(
ServerName.valueOf(s.getHostname(), s.getPort(), ServerName.NON_STARTCODE));
ServerName[] secondaryAndTertiary = secondaryAndTertiaryMap.get(currentRegion);
s = secondaryAndTertiary[0];
favoredServers.add(
ServerName.valueOf(s.getHostname(), s.getPort(), ServerName.NON_STARTCODE));
s = secondaryAndTertiary[1];
favoredServers.add(
ServerName.valueOf(s.getHostname(), s.getPort(), ServerName.NON_STARTCODE));
// Update the assignment plan
plan.updateAssignmentPlan(regions.get(i), favoredServers);
}
LOG.info(
"Generated the assignment plan for "
+ numRegions
+ " regions from table "
+ tableName
+ " with "
+ servers.size()
+ " region servers");
LOG.info(
"Assignment plan for secondary and tertiary generated "
+ "using placeSecondaryAndTertiaryWithRestrictions method");
}
}