Java Code Examples for org.apache.hadoop.hbase.MetaTableAccessor#getDaughterRegions()

/**
 * If daughters no longer hold reference to the parents, delete the parent.
 * @param parent RegionInfo of split offlined parent
 * @param rowContent Content of <code>parent</code> row in
 * <code>metaRegionName</code>
 * @return True if we removed <code>parent</code> from meta table and from
 * the filesystem.
 */
boolean cleanParent(final RegionInfo parent, Result rowContent)
throws IOException {
  // Check whether it is a merged region and if it is clean of references.
  if (MetaTableAccessor.hasMergeRegions(rowContent.rawCells())) {
    // Wait until clean of merge parent regions first
    return false;
  }
  // Run checks on each daughter split.
  PairOfSameType<RegionInfo> daughters = MetaTableAccessor.getDaughterRegions(rowContent);
  Pair<Boolean, Boolean> a = checkDaughterInFs(parent, daughters.getFirst());
  Pair<Boolean, Boolean> b = checkDaughterInFs(parent, daughters.getSecond());
  if (hasNoReferences(a) && hasNoReferences(b)) {
    String daughterA = daughters.getFirst() != null?
        daughters.getFirst().getShortNameToLog(): "null";
    String daughterB = daughters.getSecond() != null?
        daughters.getSecond().getShortNameToLog(): "null";
    LOG.debug("Deleting region " + parent.getShortNameToLog() +
      " because daughters -- " + daughterA + ", " + daughterB +
      " -- no longer hold references");
    ProcedureExecutor<MasterProcedureEnv> pe = this.services.getMasterProcedureExecutor();
    pe.submitProcedure(new GCRegionProcedure(pe.getEnvironment(), parent));
    // Remove from in-memory states
    this.services.getAssignmentManager().getRegionStates().deleteRegion(parent);
    this.services.getServerManager().removeRegion(parent);
    return true;
  }
  return false;
}
 

private RegionReplicaInfo(final Result result, final HRegionLocation location) {
  this.row = result != null ? result.getRow() : null;
  this.regionInfo = location != null ? location.getRegion() : null;
  this.regionState = (result != null && regionInfo != null)
    ? RegionStateStore.getRegionState(result, regionInfo)
    : null;
  this.serverName = location != null ? location.getServerName() : null;
  this.seqNum = (location != null) ? location.getSeqNum() : HConstants.NO_SEQNUM;
  this.targetServerName = (result != null && regionInfo != null)
    ? MetaTableAccessor.getTargetServerName(result, regionInfo.getReplicaId())
    : null;
  this.mergeRegionInfo = (result != null)
    ? MetaTableAccessor.getMergeRegionsWithName(result.rawCells())
    : null;

  if (result != null) {
    PairOfSameType<RegionInfo> daughterRegions = MetaTableAccessor.getDaughterRegions(result);
    this.splitRegionInfo = new LinkedHashMap<>();
    if (daughterRegions.getFirst() != null) {
      splitRegionInfo.put(HConstants.SPLITA_QUALIFIER_STR, daughterRegions.getFirst());
    }
    if (daughterRegions.getSecond() != null) {
      splitRegionInfo.put(HConstants.SPLITB_QUALIFIER_STR, daughterRegions.getSecond());
    }
  } else {
    this.splitRegionInfo = null;
  }
}
 

private PairOfSameType<RegionInfo> waitOnDaughters(final RegionInfo r)
    throws IOException {
  long start = System.currentTimeMillis();
  PairOfSameType<RegionInfo> pair = null;
  try (Connection conn = ConnectionFactory.createConnection(TEST_UTIL.getConfiguration());
       Table metaTable = conn.getTable(TableName.META_TABLE_NAME)) {
    Result result = null;
    RegionInfo region = null;
    while ((System.currentTimeMillis() - start) < 60000) {
      result = metaTable.get(new Get(r.getRegionName()));
      if (result == null) {
        break;
      }
      region = CatalogFamilyFormat.getRegionInfo(result);
      if (region.isSplitParent()) {
        LOG.debug(region.toString() + " IS a parent!");
        pair = MetaTableAccessor.getDaughterRegions(result);
        break;
      }
      Threads.sleep(100);
    }

    if (pair.getFirst() == null || pair.getSecond() == null) {
      throw new IOException("Failed to get daughters, for parent region: " + r);
    }
    return pair;
  }
}
 

/**
 * Scan hbase:meta, adding all regions found to the regionInfo map.
 * @throws IOException if an error is encountered
 */
boolean loadMetaEntries() throws IOException {
  ClientMetaTableAccessor.Visitor visitor = new ClientMetaTableAccessor.Visitor() {
    int countRecord = 1;

    // comparator to sort KeyValues with latest modtime
    final Comparator<Cell> comp = new Comparator<Cell>() {
      @Override
      public int compare(Cell k1, Cell k2) {
        return Long.compare(k1.getTimestamp(), k2.getTimestamp());
      }
    };

    @Override
    public boolean visit(Result result) throws IOException {
      try {

        // record the latest modification of this META record
        long ts =  Collections.max(result.listCells(), comp).getTimestamp();
        RegionLocations rl = CatalogFamilyFormat.getRegionLocations(result);
        if (rl == null) {
          emptyRegionInfoQualifiers.add(result);
          errors.reportError(ERROR_CODE.EMPTY_META_CELL,
            "Empty REGIONINFO_QUALIFIER found in hbase:meta");
          return true;
        }
        ServerName sn = null;
        if (rl.getRegionLocation(RegionInfo.DEFAULT_REPLICA_ID) == null ||
            rl.getRegionLocation(RegionInfo.DEFAULT_REPLICA_ID).getRegion() == null) {
          emptyRegionInfoQualifiers.add(result);
          errors.reportError(ERROR_CODE.EMPTY_META_CELL,
            "Empty REGIONINFO_QUALIFIER found in hbase:meta");
          return true;
        }
        RegionInfo hri = rl.getRegionLocation(RegionInfo.DEFAULT_REPLICA_ID).getRegion();
        if (!(isTableIncluded(hri.getTable())
            || hri.isMetaRegion())) {
          return true;
        }
        PairOfSameType<RegionInfo> daughters = MetaTableAccessor.getDaughterRegions(result);
        for (HRegionLocation h : rl.getRegionLocations()) {
          if (h == null || h.getRegion() == null) {
            continue;
          }
          sn = h.getServerName();
          hri = h.getRegion();

          HbckRegionInfo.MetaEntry m = null;
          if (hri.getReplicaId() == RegionInfo.DEFAULT_REPLICA_ID) {
            m = new HbckRegionInfo.MetaEntry(hri, sn, ts, daughters.getFirst(),
                daughters.getSecond());
          } else {
            m = new HbckRegionInfo.MetaEntry(hri, sn, ts, null, null);
          }
          HbckRegionInfo previous = regionInfoMap.get(hri.getEncodedName());
          if (previous == null) {
            regionInfoMap.put(hri.getEncodedName(), new HbckRegionInfo(m));
          } else if (previous.getMetaEntry() == null) {
            previous.setMetaEntry(m);
          } else {
            throw new IOException("Two entries in hbase:meta are same " + previous);
          }
        }
        List<RegionInfo> mergeParents = MetaTableAccessor.getMergeRegions(result.rawCells());
        if (mergeParents != null) {
          for (RegionInfo mergeRegion : mergeParents) {
            if (mergeRegion != null) {
              // This region is already being merged
              HbckRegionInfo hbInfo = getOrCreateInfo(mergeRegion.getEncodedName());
              hbInfo.setMerged(true);
            }
          }
        }

        // show proof of progress to the user, once for every 100 records.
        if (countRecord % 100 == 0) {
          errors.progress();
        }
        countRecord++;
        return true;
      } catch (RuntimeException e) {
        LOG.error("Result=" + result);
        throw e;
      }
    }
  };
  if (!checkMetaOnly) {
    // Scan hbase:meta to pick up user regions
    MetaTableAccessor.fullScanRegions(connection, visitor);
  }

  errors.print("");
  return true;
}
 

/**
 * Blocks until the region split is complete in hbase:meta and region server opens the daughters
 */
public static void blockUntilRegionSplit(Configuration conf, long timeout,
    final byte[] regionName, boolean waitForDaughters) throws IOException, InterruptedException {
  long start = System.currentTimeMillis();
  log("blocking until region is split:" + Bytes.toStringBinary(regionName));
  RegionInfo daughterA = null, daughterB = null;
  try (Connection conn = ConnectionFactory.createConnection(conf);
      Table metaTable = conn.getTable(TableName.META_TABLE_NAME)) {
    Result result = null;
    RegionInfo region = null;
    while ((System.currentTimeMillis() - start) < timeout) {
      result = metaTable.get(new Get(regionName));
      if (result == null) {
        break;
      }

      region = CatalogFamilyFormat.getRegionInfo(result);
      if (region.isSplitParent()) {
        log("found parent region: " + region.toString());
        PairOfSameType<RegionInfo> pair = MetaTableAccessor.getDaughterRegions(result);
        daughterA = pair.getFirst();
        daughterB = pair.getSecond();
        break;
      }
      Threads.sleep(100);
    }
    if (daughterA == null || daughterB == null) {
      throw new IOException("Failed to get daughters, daughterA=" + daughterA + ", daughterB=" +
        daughterB + ", timeout=" + timeout + ", result=" + result + ", regionName=" +
        Bytes.toString(regionName) + ", region=" + region);
    }

    // if we are here, this means the region split is complete or timed out
    if (waitForDaughters) {
      long rem = timeout - (System.currentTimeMillis() - start);
      blockUntilRegionIsInMeta(conn, rem, daughterA);

      rem = timeout - (System.currentTimeMillis() - start);
      blockUntilRegionIsInMeta(conn, rem, daughterB);

      rem = timeout - (System.currentTimeMillis() - start);
      blockUntilRegionIsOpened(conf, rem, daughterA);

      rem = timeout - (System.currentTimeMillis() - start);
      blockUntilRegionIsOpened(conf, rem, daughterB);

      // Compacting the new region to make sure references can be cleaned up
      compactAndBlockUntilDone(TEST_UTIL.getAdmin(),
        TEST_UTIL.getMiniHBaseCluster().getRegionServer(0), daughterA.getRegionName());
      compactAndBlockUntilDone(TEST_UTIL.getAdmin(),
        TEST_UTIL.getMiniHBaseCluster().getRegionServer(0), daughterB.getRegionName());

      removeCompactedFiles(conn, timeout, daughterA);
      removeCompactedFiles(conn, timeout, daughterB);
    }
  }
}