Exemple #1
0
  /**
   * @param mapping Mappings.
   * @param key Key to map.
   * @param topVer Topology version.
   * @return Near lock mapping.
   * @throws GridException If mapping for key failed.
   */
  private GridNearLockMapping<K, V> map(
      K key, @Nullable GridNearLockMapping<K, V> mapping, long topVer) throws GridException {
    assert mapping == null || mapping.node() != null;

    GridNode primary = cctx.affinity().primary(key, topVer);

    if (cctx.discovery().node(primary.id()) == null)
      // If primary node left the grid before lock acquisition, fail the whole future.
      throw newTopologyException(null, primary.id());

    if (inTx() && tx.groupLock() && !primary.isLocal())
      throw new GridException(
          "Failed to start group lock transaction (local node is not primary for "
              + " key) [key="
              + key
              + ", primaryNodeId="
              + primary.id()
              + ']');

    if (mapping == null || !primary.id().equals(mapping.node().id()))
      mapping = new GridNearLockMapping<>(primary, key);
    else mapping.addKey(key);

    return mapping;
  }
Exemple #2
0
  /**
   * Completeness callback.
   *
   * @param success {@code True} if lock was acquired.
   * @param distribute {@code True} if need to distribute lock removal in case of failure.
   * @return {@code True} if complete by this operation.
   */
  private boolean onComplete(boolean success, boolean distribute) {
    if (log.isDebugEnabled())
      log.debug(
          "Received onComplete(..) callback [success="
              + success
              + ", distribute="
              + distribute
              + ", fut="
              + this
              + ']');

    if (!success) undoLocks(distribute);

    if (tx != null) cctx.tm().txContext(tx);

    if (super.onDone(success, err.get())) {
      if (log.isDebugEnabled()) log.debug("Completing future: " + this);

      // Clean up.
      cctx.mvcc().removeFuture(this);

      if (timeoutObj != null) cctx.time().removeTimeoutObject(timeoutObj);

      return true;
    }

    return false;
  }
  /** {@inheritDoc} */
  @Override
  public boolean onDone(GridCacheTx tx, Throwable err) {
    if ((initialized() || err != null) && super.onDone(tx, err)) {
      if (error() instanceof GridCacheTxHeuristicException) {
        long topVer = this.tx.topologyVersion();

        for (GridCacheTxEntry<K, V> e : this.tx.writeMap().values()) {
          try {
            if (e.op() != NOOP && !cctx.affinity().localNode(e.key(), topVer)) {
              GridCacheEntryEx<K, V> cacheEntry = cctx.cache().peekEx(e.key());

              if (cacheEntry != null) cacheEntry.invalidate(null, this.tx.xidVersion());
            }
          } catch (Throwable t) {
            U.error(log, "Failed to invalidate entry.", t);

            if (t instanceof Error) throw (Error) t;
          }
        }
      }

      // Don't forget to clean up.
      cctx.mvcc().removeFuture(this);

      return true;
    }

    return false;
  }
  /** {@inheritDoc} */
  @Override
  public void prepareMarshal(GridCacheContext<K, V> ctx) throws GridException {
    super.prepareMarshal(ctx);

    if (entries != null) {
      if (ctx.deploymentEnabled()) prepareObjects(entries, ctx);

      entriesBytes = ctx.marshaller().marshal(entries);
    }
  }
  /** {@inheritDoc} */
  @SuppressWarnings("TypeMayBeWeakened")
  @Nullable
  private Collection<byte[]> marshalFieldsCollection(
      @Nullable Collection<Object> col, GridCacheContext<K, V> ctx) throws GridException {
    assert ctx != null;

    if (col == null) return null;

    Collection<List<Object>> col0 = new ArrayList<>(col.size());

    for (Object o : col) {
      List<GridIndexingEntity<?>> list = (List<GridIndexingEntity<?>>) o;
      List<Object> list0 = new ArrayList<>(list.size());

      for (GridIndexingEntity<?> ent : list) {
        if (ent.bytes() != null) list0.add(ent.bytes());
        else {
          if (ctx.deploymentEnabled()) prepareObject(ent.value(), ctx);

          list0.add(CU.marshal(ctx, ent.value()));
        }
      }

      col0.add(list0);
    }

    return marshalCollection(col0, ctx);
  }
  /** {@inheritDoc} */
  @SuppressWarnings("TypeMayBeWeakened")
  @Nullable
  private Collection<Object> unmarshalFieldsCollection(
      @Nullable Collection<byte[]> byteCol, GridCacheContext<K, V> ctx, ClassLoader ldr)
      throws GridException {
    assert ctx != null;
    assert ldr != null;

    Collection<Object> col = unmarshalCollection(byteCol, ctx, ldr);
    Collection<Object> col0 = null;

    if (col != null) {
      col0 = new ArrayList<>(col.size());

      for (Object o : col) {
        List<Object> list = (List<Object>) o;
        List<Object> list0 = new ArrayList<>(list.size());

        for (Object obj : list)
          list0.add(obj != null ? ctx.marshaller().unmarshal((byte[]) obj, ldr) : null);

        col0.add(list0);
      }
    }

    return col0;
  }
  /**
   * @param ctx Cache context.
   * @param key Cache key.
   * @param hash Key hash value.
   * @param val Entry value.
   * @param next Next entry in the linked list.
   * @param ttl Time to live.
   */
  public GridDhtCacheEntry(
      GridCacheContext<K, V> ctx, K key, int hash, V val, GridCacheMapEntry<K, V> next, long ttl) {
    super(ctx, key, hash, val, next, ttl);

    // Record this entry with partition.
    locPart = ctx.dht().topology().onAdded(this);
  }
  /** {@inheritDoc} */
  @Override
  public GridCacheEntry<K, V> wrap(boolean prjAware) {
    GridCacheContext<K, V> nearCtx = cctx.dht().near().context();

    GridCacheProjectionImpl<K, V> prjPerCall = nearCtx.projectionPerCall();

    if (prjPerCall != null && prjAware)
      return new GridPartitionedCacheEntryImpl<K, V>(prjPerCall, nearCtx, key, this);

    GridCacheEntryImpl<K, V> wrapper = this.wrapper;

    if (wrapper == null)
      this.wrapper = wrapper = new GridPartitionedCacheEntryImpl<K, V>(null, nearCtx, key, this);

    return wrapper;
  }
  /** @param m Mapping. */
  @SuppressWarnings({"unchecked"})
  private void finish(GridDistributedTxMapping<K, V> m) {
    GridRichNode n = m.node();

    assert !m.empty();

    GridNearTxFinishRequest req =
        new GridNearTxFinishRequest<K, V>(
            futId,
            tx.xidVersion(),
            tx.commitVersion(),
            tx.threadId(),
            commit,
            tx.isInvalidate(),
            m.explicitLock(),
            tx.topologyVersion(),
            null,
            null,
            null,
            commit && tx.pessimistic() ? m.writes() : null,
            tx.syncCommit() && commit || tx.syncRollback() && !commit);

    // If this is the primary node for the keys.
    if (n.isLocal()) {
      req.miniId(GridUuid.randomUuid());

      if (CU.DHT_ENABLED) {
        GridFuture<GridCacheTx> fut =
            commit ? dht().commitTx(n.id(), req) : dht().rollbackTx(n.id(), req);

        // Add new future.
        add(fut);
      } else
        // Add done future for testing.
        add(new GridFinishedFuture<GridCacheTx>(ctx));
    } else {
      MiniFuture fut = new MiniFuture(m);

      req.miniId(fut.futureId());

      add(fut); // Append new future.

      try {
        cctx.io().send(n, req);

        // If we don't wait for result, then mark future as done.
        if (!isSync() && !m.explicitLock()) fut.onDone();
      } catch (GridTopologyException e) {
        // Remove previous mapping.
        mappings.remove(m.node().id());

        fut.onResult(e);
      } catch (GridException e) {
        // Fail the whole thing.
        fut.onResult(e);
      }
    }
  }
  /**
   * @param entry Transaction entry.
   * @param nodes Nodes.
   */
  private void map(GridCacheTxEntry<K, V> entry, Collection<GridRichNode> nodes) {
    GridRichNode primary = CU.primary0(cctx.affinity(entry.key(), nodes));

    GridDistributedTxMapping<K, V> t = mappings.get(primary.id());

    if (t == null) mappings.put(primary.id(), t = new GridDistributedTxMapping<K, V>(primary));

    t.add(entry);
  }
  /** {@inheritDoc} */
  @Override
  public void prepareMarshal(GridCacheContext<K, V> ctx) throws GridException {
    super.prepareMarshal(ctx);

    if (err != null) errBytes = ctx.marshaller().marshal(err);

    metaDataBytes = marshalCollection(metadata, ctx);
    dataBytes = fields ? marshalFieldsCollection(data, ctx) : marshalCollection(data, ctx);

    if (ctx.deploymentEnabled() && !F.isEmpty(data)) {
      for (Object o : data) {
        if (o instanceof Map.Entry) {
          Map.Entry e = (Map.Entry) o;

          prepareObject(e.getKey(), ctx);
          prepareObject(e.getValue(), ctx);
        }
      }
    }
  }
  /** {@inheritDoc} */
  @Override
  public boolean onDone(GridCacheTx tx, Throwable err) {
    if (initialized() && super.onDone(tx, err)) {
      // Don't forget to clean up.
      cctx.mvcc().removeFuture(this);

      return true;
    }

    return false;
  }
Exemple #13
0
  /**
   * Undoes all locks.
   *
   * @param dist If {@code true}, then remove locks from remote nodes as well.
   */
  private void undoLocks(boolean dist) {
    // Transactions will undo during rollback.
    if (dist && tx == null) cctx.nearTx().removeLocks(lockVer, keys);
    else {
      if (tx != null) {
        if (tx.setRollbackOnly()) {
          if (log.isDebugEnabled())
            log.debug(
                "Marked transaction as rollback only because locks could not be acquired: " + tx);
        } else if (log.isDebugEnabled())
          log.debug(
              "Transaction was not marked rollback-only while locks were not acquired: " + tx);
      }

      for (GridCacheEntryEx<K, V> e : entriesCopy()) {
        try {
          e.removeLock(lockVer);
        } catch (GridCacheEntryRemovedException ignored) {
          while (true) {
            try {
              e = cctx.cache().peekEx(e.key());

              if (e != null) e.removeLock(lockVer);

              break;
            } catch (GridCacheEntryRemovedException ignore) {
              if (log.isDebugEnabled())
                log.debug(
                    "Attempted to remove lock on removed entry (will retry) [ver="
                        + lockVer
                        + ", entry="
                        + e
                        + ']');
            }
          }
        }
      }
    }

    cctx.mvcc().recheckPendingLocks();
  }
  /** {@inheritDoc} */
  @Override
  public void finishUnmarshal(GridCacheContext<K, V> ctx, ClassLoader ldr) throws GridException {
    super.finishUnmarshal(ctx, ldr);

    if (errBytes != null) err = ctx.marshaller().unmarshal(errBytes, ldr);

    metadata = unmarshalCollection(metaDataBytes, ctx, ldr);
    data =
        fields
            ? unmarshalFieldsCollection(dataBytes, ctx, ldr)
            : unmarshalCollection(dataBytes, ctx, ldr);
  }
  /** {@inheritDoc} */
  @Override
  public void prepareMarshal(GridCacheContext<K, V> ctx) throws GridException {
    super.prepareMarshal(ctx);

    if (map != null) {
      if (ctx.deploymentEnabled()) {
        for (K key : map.keySet()) prepareObject(key, ctx);
      }

      mapBytes = CU.marshal(ctx, map);
    }
  }
Exemple #16
0
  /**
   * @param cctx Registry.
   * @param keys Keys to lock.
   * @param tx Transaction.
   * @param read Read flag.
   * @param retval Flag to return value or not.
   * @param timeout Lock acquisition timeout.
   * @param filter Filter.
   */
  public GridNearLockFuture(
      GridCacheContext<K, V> cctx,
      Collection<? extends K> keys,
      @Nullable GridNearTxLocal<K, V> tx,
      boolean read,
      boolean retval,
      long timeout,
      GridPredicate<GridCacheEntry<K, V>>[] filter) {
    super(cctx.kernalContext(), CU.boolReducer());
    assert cctx != null;
    assert keys != null;

    this.cctx = cctx;
    this.keys = keys;
    this.tx = tx;
    this.read = read;
    this.retval = retval;
    this.timeout = timeout;
    this.filter = filter;

    threadId = tx == null ? Thread.currentThread().getId() : tx.threadId();

    lockVer = tx != null ? tx.xidVersion() : cctx.versions().next();

    futId = GridUuid.randomUuid();

    entries = new ArrayList<>(keys.size());

    log = U.logger(ctx, logRef, GridNearLockFuture.class);

    if (timeout > 0) {
      timeoutObj = new LockTimeoutObject();

      cctx.time().addTimeoutObject(timeoutObj);
    }

    valMap = new ConcurrentHashMap8<>(keys.size(), 1f);
  }
Exemple #17
0
  /**
   * Acquires topology future and checks it completeness under the read lock. If it is not complete,
   * will asynchronously wait for it's completeness and then try again.
   */
  void mapOnTopology() {
    // We must acquire topology snapshot from the topology version future.
    try {
      cctx.topology().readLock();

      try {
        GridDhtTopologyFuture fut = cctx.topologyVersionFuture();

        if (fut.isDone()) {
          GridDiscoveryTopologySnapshot snapshot = fut.topologySnapshot();

          if (tx != null) {
            tx.topologyVersion(snapshot.topologyVersion());
            tx.topologySnapshot(snapshot);
          }

          topSnapshot.compareAndSet(null, snapshot);

          map(keys);

          markInitialized();
        } else {
          fut.listenAsync(
              new CI1<GridFuture<Long>>() {
                @Override
                public void apply(GridFuture<Long> t) {
                  mapOnTopology();
                }
              });
        }
      } finally {
        cctx.topology().readUnlock();
      }
    } catch (GridException e) {
      onDone(e);
    }
  }
  /**
   * @param cctx Context.
   * @param tx Transaction.
   * @param commit Commit flag.
   */
  public GridNearTxFinishFuture(
      GridCacheContext<K, V> cctx, GridNearTxLocal<K, V> tx, boolean commit) {
    super(cctx.kernalContext(), F.<GridCacheTx>identityReducer(tx));

    assert cctx != null;

    this.cctx = cctx;
    this.tx = tx;
    this.commit = commit;

    mappings = tx.mappings();

    futId = GridUuid.randomUuid();

    log = U.logger(ctx, logRef, GridNearTxFinishFuture.class);
  }
  /**
   * Default constructor.
   *
   * @param name Atomic stamped name.
   * @param key Atomic stamped key.
   * @param atomicView Atomic projection.
   * @param ctx Cache context.
   */
  public GridCacheAtomicStampedImpl(
      String name,
      GridCacheInternalKey key,
      GridCacheProjection<GridCacheInternalKey, GridCacheAtomicStampedValue<T, S>> atomicView,
      GridCacheContext ctx) {
    assert key != null;
    assert atomicView != null;
    assert ctx != null;
    assert name != null;

    this.ctx = ctx;
    this.key = key;
    this.atomicView = atomicView;
    this.name = name;

    log = ctx.gridConfig().getGridLogger().getLogger(getClass());
  }
Exemple #20
0
  /**
   * @param cached Entry to check.
   * @return {@code True} if filter passed.
   */
  private boolean filter(GridCacheEntryEx<K, V> cached) {
    try {
      if (!cctx.isAll(cached, filter)) {
        if (log.isDebugEnabled())
          log.debug("Filter didn't pass for entry (will fail lock): " + cached);

        onFailed(true);

        return false;
      }

      return true;
    } catch (GridException e) {
      onError(e);

      return false;
    }
  }
Exemple #21
0
  /** @return {@code True} if locks have been acquired. */
  private boolean checkLocks() {
    if (!isDone() && initialized() && !hasPending()) {
      for (int i = 0; i < entries.size(); i++) {
        while (true) {
          GridCacheEntryEx<K, V> cached = entries.get(i);

          try {
            if (!locked(cached)) {
              if (log.isDebugEnabled())
                log.debug(
                    "Lock is still not acquired for entry (will keep waiting) [entry="
                        + cached
                        + ", fut="
                        + this
                        + ']');

              return false;
            }

            break;
          }
          // Possible in concurrent cases, when owner is changed after locks
          // have been released or cancelled.
          catch (GridCacheEntryRemovedException ignore) {
            if (log.isDebugEnabled())
              log.debug("Got removed entry in onOwnerChanged method (will retry): " + cached);

            // Replace old entry with new one.
            entries.set(i, (GridDistributedCacheEntry<K, V>) cctx.cache().entryEx(cached.key()));
          }
        }
      }

      if (log.isDebugEnabled())
        log.debug("Local lock acquired for entries [fut=" + this + ", entries=" + entries + "]");

      onComplete(true, true);

      return true;
    }

    return false;
  }
Exemple #22
0
  /**
   * Basically, future mapping consists from two parts. First, we must determine the topology
   * version this future will map on. Locking is performed within a user transaction, we must
   * continue to map keys on the same topology version as it started. If topology version is
   * undefined, we get current topology future and wait until it completes so the topology is ready
   * to use.
   *
   * <p>During the second part we map keys to primary nodes using topology snapshot we obtained
   * during the first part. Note that if primary node leaves grid, the future will fail and
   * transaction will be rolled back.
   */
  void map() {
    // Obtain the topology version to use.
    GridDiscoveryTopologySnapshot snapshot =
        tx != null
            ? tx.topologySnapshot()
            : cctx.mvcc().lastExplicitLockTopologySnapshot(Thread.currentThread().getId());

    if (snapshot != null) {
      // Continue mapping on the same topology version as it was before.
      topSnapshot.compareAndSet(null, snapshot);

      map(keys);

      markInitialized();

      return;
    }

    // Must get topology snapshot and map on that version.
    mapOnTopology();
  }
Exemple #23
0
  /**
   * Maps keys to nodes. Note that we can not simply group keys by nodes and send lock request as
   * such approach does not preserve order of lock acquisition. Instead, keys are split in
   * continuous groups belonging to one primary node and locks for these groups are acquired
   * sequentially.
   *
   * @param keys Keys.
   */
  private void map(Iterable<? extends K> keys) {
    try {
      GridDiscoveryTopologySnapshot snapshot = topSnapshot.get();

      assert snapshot != null;

      long topVer = snapshot.topologyVersion();

      assert topVer > 0;

      if (CU.affinityNodes(cctx, topVer).isEmpty()) {
        onDone(
            new GridTopologyException(
                "Failed to map keys for near-only cache (all "
                    + "partition nodes left the grid)."));

        return;
      }

      ConcurrentLinkedDeque8<GridNearLockMapping<K, V>> mappings = new ConcurrentLinkedDeque8<>();

      // Assign keys to primary nodes.
      GridNearLockMapping<K, V> map = null;

      for (K key : keys) {
        GridNearLockMapping<K, V> updated = map(key, map, topVer);

        // If new mapping was created, add to collection.
        if (updated != map) mappings.add(updated);

        map = updated;
      }

      if (isDone()) {
        if (log.isDebugEnabled()) log.debug("Abandoning (re)map because future is done: " + this);

        return;
      }

      if (log.isDebugEnabled())
        log.debug("Starting (re)map for mappings [mappings=" + mappings + ", fut=" + this + ']');

      // Create mini futures.
      for (Iterator<GridNearLockMapping<K, V>> iter = mappings.iterator(); iter.hasNext(); ) {
        GridNearLockMapping<K, V> mapping = iter.next();

        GridNode node = mapping.node();
        Collection<K> mappedKeys = mapping.mappedKeys();

        assert !mappedKeys.isEmpty();

        GridNearLockRequest<K, V> req = null;

        Collection<K> distributedKeys = new ArrayList<>(mappedKeys.size());

        boolean explicit = false;

        for (K key : mappedKeys) {
          while (true) {
            GridNearCacheEntry<K, V> entry = null;

            try {
              entry = cctx.near().entryExx(key, topVer);

              if (!cctx.isAll(entry.wrap(false), filter)) {
                if (log.isDebugEnabled())
                  log.debug("Entry being locked did not pass filter (will not lock): " + entry);

                onComplete(false, false);

                return;
              }

              // Removed exception may be thrown here.
              GridCacheMvccCandidate<K> cand = addEntry(topVer, entry, node.id());

              if (isDone()) {
                if (log.isDebugEnabled())
                  log.debug(
                      "Abandoning (re)map because future is done after addEntry attempt "
                          + "[fut="
                          + this
                          + ", entry="
                          + entry
                          + ']');

                return;
              }

              if (cand != null) {
                if (tx == null && !cand.reentry())
                  cctx.mvcc().addExplicitLock(threadId, cand, snapshot);

                GridTuple3<GridCacheVersion, V, byte[]> val = entry.versionedValue();

                if (val == null) {
                  GridDhtCacheEntry<K, V> dhtEntry = dht().peekExx(key);

                  try {
                    if (dhtEntry != null) val = dhtEntry.versionedValue(topVer);
                  } catch (GridCacheEntryRemovedException ignored) {
                    assert dhtEntry.obsolete()
                        : " Got removed exception for non-obsolete entry: " + dhtEntry;

                    if (log.isDebugEnabled())
                      log.debug(
                          "Got removed exception for DHT entry in map (will ignore): " + dhtEntry);
                  }
                }

                GridCacheVersion dhtVer = null;

                if (val != null) {
                  dhtVer = val.get1();

                  valMap.put(key, val);
                }

                if (!cand.reentry()) {
                  if (req == null) {
                    req =
                        new GridNearLockRequest<>(
                            topVer,
                            cctx.nodeId(),
                            threadId,
                            futId,
                            lockVer,
                            inTx(),
                            implicitTx(),
                            implicitSingleTx(),
                            read,
                            isolation(),
                            isInvalidate(),
                            timeout,
                            syncCommit(),
                            syncRollback(),
                            mappedKeys.size(),
                            inTx() ? tx.size() : mappedKeys.size(),
                            inTx() ? tx.groupLockKey() : null,
                            inTx() && tx.partitionLock(),
                            inTx() ? tx.subjectId() : null);

                    mapping.request(req);
                  }

                  distributedKeys.add(key);

                  GridCacheTxEntry<K, V> writeEntry = tx != null ? tx.writeMap().get(key) : null;

                  if (tx != null) tx.addKeyMapping(key, mapping.node());

                  req.addKeyBytes(
                      key,
                      node.isLocal() ? null : entry.getOrMarshalKeyBytes(),
                      retval && dhtVer == null,
                      dhtVer, // Include DHT version to match remote DHT entry.
                      writeEntry,
                      inTx() ? tx.entry(key).drVersion() : null,
                      cctx);

                  // Clear transfer required flag since we are sending message.
                  if (writeEntry != null) writeEntry.transferRequired(false);
                }

                if (cand.reentry())
                  explicit = tx != null && !entry.hasLockCandidate(tx.xidVersion());
              } else
                // Ignore reentries within transactions.
                explicit = tx != null && !entry.hasLockCandidate(tx.xidVersion());

              if (explicit) tx.addKeyMapping(key, mapping.node());

              break;
            } catch (GridCacheEntryRemovedException ignored) {
              assert entry.obsolete() : "Got removed exception on non-obsolete entry: " + entry;

              if (log.isDebugEnabled())
                log.debug("Got removed entry in lockAsync(..) method (will retry): " + entry);
            }
          }

          // Mark mapping explicit lock flag.
          if (explicit) {
            boolean marked = tx != null && tx.markExplicit(node.id());

            assert tx == null || marked;
          }
        }

        if (!distributedKeys.isEmpty()) mapping.distributedKeys(distributedKeys);
        else {
          assert mapping.request() == null;

          iter.remove();
        }
      }

      cctx.mvcc().recheckPendingLocks();

      proceedMapping(mappings);
    } catch (GridException ex) {
      onError(ex);
    }
  }
Exemple #24
0
 /** @return DHT cache. */
 private GridDhtTransactionalCacheAdapter<K, V> dht() {
   return cctx.nearTx().dht();
 }
 /** @return DHT cache. */
 private GridDhtCache<K, V> dht() {
   return cctx.near().dht();
 }
 /** @return Synchronous flag. */
 private boolean isSync() {
   return cctx.config().getWriteSynchronizationMode()
       != GridCacheWriteSynchronizationMode.FULL_ASYNC;
 }
  /** {@inheritDoc} */
  @Override
  public void finishUnmarshal(GridCacheContext<K, V> ctx, ClassLoader ldr) throws GridException {
    super.finishUnmarshal(ctx, ldr);

    if (entriesBytes != null) entries = ctx.marshaller().unmarshal(entriesBytes, ldr);
  }
Exemple #28
0
  /**
   * Gets next near lock mapping and either acquires dht locks locally or sends near lock request to
   * remote primary node.
   *
   * @param mappings Queue of mappings.
   * @throws GridException If mapping can not be completed.
   */
  private void proceedMapping(final ConcurrentLinkedDeque8<GridNearLockMapping<K, V>> mappings)
      throws GridException {
    GridNearLockMapping<K, V> map = mappings.poll();

    // If there are no more mappings to process, complete the future.
    if (map == null) return;

    final GridNearLockRequest<K, V> req = map.request();
    final Collection<K> mappedKeys = map.distributedKeys();
    final GridNode node = map.node();

    if (filter != null && filter.length != 0) req.filter(filter, cctx);

    if (node.isLocal()) {
      req.miniId(GridUuid.randomUuid());

      if (log.isDebugEnabled()) log.debug("Before locally locking near request: " + req);

      GridFuture<GridNearLockResponse<K, V>> fut;

      if (CU.DHT_ENABLED) fut = dht().lockAllAsync(cctx.localNode(), req, filter);
      else {
        // Create dummy values for testing.
        GridNearLockResponse<K, V> res =
            new GridNearLockResponse<>(lockVer, futId, null, false, 1, null);

        res.addValueBytes(null, null, true, lockVer, lockVer, cctx);

        fut = new GridFinishedFuture<>(ctx, res);
      }

      // Add new future.
      add(
          new GridEmbeddedFuture<>(
              cctx.kernalContext(),
              fut,
              new C2<GridNearLockResponse<K, V>, Exception, Boolean>() {
                @Override
                public Boolean apply(GridNearLockResponse<K, V> res, Exception e) {
                  if (CU.isLockTimeoutOrCancelled(e)
                      || (res != null && CU.isLockTimeoutOrCancelled(res.error()))) return false;

                  if (e != null) {
                    onError(e);

                    return false;
                  }

                  if (res == null) {
                    onError(new GridException("Lock response is null for future: " + this));

                    return false;
                  }

                  if (res.error() != null) {
                    onError(res.error());

                    return false;
                  }

                  if (log.isDebugEnabled())
                    log.debug(
                        "Acquired lock for local DHT mapping [locId="
                            + cctx.nodeId()
                            + ", mappedKeys="
                            + mappedKeys
                            + ", fut="
                            + GridNearLockFuture.this
                            + ']');

                  try {
                    int i = 0;

                    for (K k : mappedKeys) {
                      while (true) {
                        GridNearCacheEntry<K, V> entry =
                            cctx.near().entryExx(k, req.topologyVersion());

                        try {
                          GridTuple3<GridCacheVersion, V, byte[]> oldValTup =
                              valMap.get(entry.key());

                          boolean hasBytes = entry.hasValue();
                          V oldVal = entry.rawGet();
                          V newVal = res.value(i);
                          byte[] newBytes = res.valueBytes(i);

                          GridCacheVersion dhtVer = res.dhtVersion(i);
                          GridCacheVersion mappedVer = res.mappedVersion(i);

                          // On local node don't record twice if DHT cache already recorded.
                          boolean record =
                              retval && oldValTup != null && oldValTup.get1().equals(dhtVer);

                          if (newVal == null) {
                            if (oldValTup != null) {
                              if (oldValTup.get1().equals(dhtVer)) {
                                newVal = oldValTup.get2();

                                newBytes = oldValTup.get3();
                              }

                              oldVal = oldValTup.get2();
                            }
                          }

                          // Lock is held at this point, so we can set the
                          // returned value if any.
                          entry.resetFromPrimary(newVal, newBytes, lockVer, dhtVer, node.id());

                          entry.readyNearLock(
                              lockVer,
                              mappedVer,
                              res.committedVersions(),
                              res.rolledbackVersions(),
                              res.pending());

                          if (inTx() && implicitTx() && tx.onePhaseCommit()) {
                            boolean pass = res.filterResult(i);

                            tx.entry(k).filters(pass ? CU.<K, V>empty() : CU.<K, V>alwaysFalse());
                          }

                          if (record) {
                            if (cctx.events().isRecordable(EVT_CACHE_OBJECT_READ))
                              cctx.events()
                                  .addEvent(
                                      entry.partition(),
                                      entry.key(),
                                      tx,
                                      null,
                                      EVT_CACHE_OBJECT_READ,
                                      newVal,
                                      newVal != null,
                                      oldVal,
                                      hasBytes,
                                      CU.subjectId(tx, cctx));

                            cctx.cache().metrics0().onRead(oldVal != null);
                          }

                          if (log.isDebugEnabled())
                            log.debug(
                                "Processed response for entry [res="
                                    + res
                                    + ", entry="
                                    + entry
                                    + ']');

                          break; // Inner while loop.
                        } catch (GridCacheEntryRemovedException ignored) {
                          if (log.isDebugEnabled())
                            log.debug(
                                "Failed to add candidates because entry was "
                                    + "removed (will renew).");

                          // Replace old entry with new one.
                          entries.set(
                              i,
                              (GridDistributedCacheEntry<K, V>) cctx.cache().entryEx(entry.key()));
                        }
                      }

                      i++; // Increment outside of while loop.
                    }

                    // Proceed and add new future (if any) before completing embedded future.
                    proceedMapping(mappings);
                  } catch (GridException ex) {
                    onError(ex);

                    return false;
                  }

                  return true;
                }
              }));
    } else {
      final MiniFuture fut = new MiniFuture(node, mappedKeys, mappings);

      req.miniId(fut.futureId());

      add(fut); // Append new future.

      GridFuture<?> txSync = null;

      if (inTx()) txSync = cctx.tm().awaitFinishAckAsync(node.id(), tx.threadId());

      if (txSync == null || txSync.isDone()) {
        try {
          if (log.isDebugEnabled())
            log.debug("Sending near lock request [node=" + node.id() + ", req=" + req + ']');

          cctx.io().send(node, req);
        } catch (GridTopologyException ex) {
          assert fut != null;

          fut.onResult(ex);
        }
      } else {
        txSync.listenAsync(
            new CI1<GridFuture<?>>() {
              @Override
              public void apply(GridFuture<?> t) {
                try {
                  if (log.isDebugEnabled())
                    log.debug(
                        "Sending near lock request [node=" + node.id() + ", req=" + req + ']');

                  cctx.io().send(node, req);
                } catch (GridTopologyException ex) {
                  assert fut != null;

                  fut.onResult(ex);
                } catch (GridException e) {
                  onError(e);
                }
              }
            });
      }
    }
  }