Examples with IDBlock org.janusgraph.diskstorage.IDBlock used on opensource projects

Example 1 with IDBlock

use of org.janusgraph.diskstorage.IDBlock in project janusgraph by JanusGraph.

the class IDPoolTest method testAllocationTimeoutAndRecovery.

@Test
public void testAllocationTimeoutAndRecovery() throws BackendException {
    IMocksControl ctrl = EasyMock.createStrictControl();
    final int partition = 42;
    final int idNamespace = 777;
    final Duration timeout = Duration.ofSeconds(1L);
    final IDAuthority mockAuthority = ctrl.createMock(IDAuthority.class);
    // Sleep for two seconds, then throw a BackendException
    // this whole delegate could be deleted if we abstracted StandardIDPool's internal executor and stopwatches
    expect(mockAuthority.getIDBlock(partition, idNamespace, timeout)).andDelegateTo(new IDAuthority() {

        @Override
        public IDBlock getIDBlock(int partition, int idNamespace, Duration timeout) throws BackendException {
            assertThrows(InterruptedException.class, () -> Thread.sleep(2000L));
            throw new TemporaryBackendException("slow backend");
        }

        @Override
        public List<KeyRange> getLocalIDPartition() {
            throw new IllegalArgumentException();
        }

        @Override
        public void setIDBlockSizer(IDBlockSizer sizer) {
            throw new IllegalArgumentException();
        }

        @Override
        public void close() {
            throw new IllegalArgumentException();
        }

        @Override
        public String getUniqueID() {
            throw new IllegalArgumentException();
        }

        @Override
        public boolean supportsInterruption() {
            return true;
        }
    });
    expect(mockAuthority.getIDBlock(partition, idNamespace, timeout)).andReturn(new IDBlock() {

        @Override
        public long numIds() {
            return 2;
        }

        @Override
        public long getId(long index) {
            return 200;
        }
    });
    expect(mockAuthority.supportsInterruption()).andStubReturn(true);
    ctrl.replay();
    StandardIDPool pool = new StandardIDPool(mockAuthority, partition, idNamespace, Integer.MAX_VALUE, timeout, 0.1);
    assertThrows(JanusGraphException.class, pool::nextID);
    long nextID = pool.nextID();
    assertEquals(200, nextID);
    ctrl.verify();
}

Example 2 with IDBlock

use of org.janusgraph.diskstorage.IDBlock in project janusgraph by JanusGraph.

the class ConsistentKeyIDAuthority method getIDBlock.

@Override
public synchronized IDBlock getIDBlock(final int partition, final int idNamespace, Duration timeout) throws BackendException {
    Preconditions.checkArgument(partition >= 0 && partition < (1 << partitionBitWidth), "Invalid partition id [%s] for bit width [%s]", partition, partitionBitWidth);
    // can be any non-negative value
    Preconditions.checkArgument(idNamespace >= 0);
    final Timer methodTime = times.getTimer().start();
    final long blockSize = getBlockSize(idNamespace);
    final long idUpperBound = getIdUpperBound(idNamespace);
    final int maxAvailableBits = (VariableLong.unsignedBitLength(idUpperBound) - 1) - uniqueIdBitWidth;
    Preconditions.checkArgument(maxAvailableBits > 0, "Unique id bit width [%s] is too wide for id-namespace [%s] id bound [%s]", uniqueIdBitWidth, idNamespace, idUpperBound);
    final long idBlockUpperBound = (1L << maxAvailableBits);
    final List<Integer> exhaustedUniquePIDs = new ArrayList<>(randomUniqueIDLimit);
    Duration backoffMS = idApplicationWaitMS;
    Preconditions.checkArgument(idBlockUpperBound > blockSize, "Block size [%s] is larger than upper bound [%s] for bit width [%s]", blockSize, idBlockUpperBound, uniqueIdBitWidth);
    while (methodTime.elapsed().compareTo(timeout) < 0) {
        final int uniquePID = getUniquePartitionID();
        final StaticBuffer partitionKey = getPartitionKey(partition, idNamespace, uniquePID);
        try {
            long nextStart = getCurrentID(partitionKey);
            if (idBlockUpperBound - blockSize <= nextStart) {
                log.info("ID overflow detected on partition({})-namespace({}) with uniqueid {}. Current id {}, block size {}, and upper bound {} for bit width {}.", partition, idNamespace, uniquePID, nextStart, blockSize, idBlockUpperBound, uniqueIdBitWidth);
                if (randomizeUniqueId) {
                    exhaustedUniquePIDs.add(uniquePID);
                    if (exhaustedUniquePIDs.size() == randomUniqueIDLimit)
                        throw new IDPoolExhaustedException(String.format("Exhausted %d uniqueid(s) on partition(%d)-namespace(%d): %s", exhaustedUniquePIDs.size(), partition, idNamespace, StringUtils.join(exhaustedUniquePIDs, ",")));
                    else
                        throw new UniqueIDExhaustedException(String.format("Exhausted ID partition(%d)-namespace(%d) with uniqueid %d (uniqueid attempt %d/%d)", partition, idNamespace, uniquePID, exhaustedUniquePIDs.size(), randomUniqueIDLimit));
                }
                throw new IDPoolExhaustedException("Exhausted id block for partition(" + partition + ")-namespace(" + idNamespace + ") with upper bound: " + idBlockUpperBound);
            }
            // calculate the start (inclusive) and end (exclusive) of the allocation we're about to attempt
            assert idBlockUpperBound - blockSize > nextStart;
            long nextEnd = nextStart + blockSize;
            StaticBuffer target = null;
            // attempt to write our claim on the next id block
            boolean success = false;
            try {
                Timer writeTimer = times.getTimer().start();
                target = getBlockApplication(nextEnd, writeTimer.getStartTime());
                // copy for the inner class
                final StaticBuffer finalTarget = target;
                BackendOperation.execute(txh -> {
                    idStore.mutate(partitionKey, Collections.singletonList(StaticArrayEntry.of(finalTarget)), KeyColumnValueStore.NO_DELETIONS, txh);
                    return true;
                }, this, times);
                writeTimer.stop();
                final boolean distributed = manager.getFeatures().isDistributed();
                Duration writeElapsed = writeTimer.elapsed();
                if (idApplicationWaitMS.compareTo(writeElapsed) < 0 && distributed) {
                    throw new TemporaryBackendException("Wrote claim for id block [" + nextStart + ", " + nextEnd + ") in " + (writeElapsed) + " => too slow, threshold is: " + idApplicationWaitMS);
                } else {
                    assert 0 != target.length();
                    final StaticBuffer[] slice = getBlockSlice(nextEnd);
                    if (distributed) {
                        sleepAndConvertInterrupts(idApplicationWaitMS.plus(waitGracePeriod));
                    }
                    // Read all id allocation claims on this partition, for the counter value we're claiming
                    final List<Entry> blocks = BackendOperation.execute((BackendOperation.Transactional<List<Entry>>) txh -> idStore.getSlice(new KeySliceQuery(partitionKey, slice[0], slice[1]), txh), this, times);
                    if (blocks == null)
                        throw new TemporaryBackendException("Could not read from storage");
                    if (blocks.isEmpty())
                        throw new PermanentBackendException("It seems there is a race-condition in the block application. " + "If you have multiple JanusGraph instances running on one physical machine, ensure that they have unique machine idAuthorities");
                    /* If our claim is the lexicographically first one, then our claim
                         * is the most senior one and we own this id block
                         */
                    if (target.equals(blocks.get(0).getColumnAs(StaticBuffer.STATIC_FACTORY))) {
                        ConsistentKeyIDBlock idBlock = new ConsistentKeyIDBlock(nextStart, blockSize, uniqueIdBitWidth, uniquePID);
                        if (log.isDebugEnabled()) {
                            log.debug("Acquired ID block [{}] on partition({})-namespace({}) (my rid is {})", idBlock, partition, idNamespace, uid);
                        }
                        success = true;
                        return idBlock;
                    } else {
                        // Another claimant beat us to this id block -- try again.
                        log.debug("Failed to acquire ID block [{},{}) (another host claimed it first)", nextStart, nextEnd);
                    }
                }
            } finally {
                if (!success && null != target) {
                    // Delete claim to not pollute id space
                    for (int attempt = 0; attempt < ROLLBACK_ATTEMPTS; attempt++) {
                        try {
                            // copy for the inner class
                            final StaticBuffer finalTarget = target;
                            BackendOperation.execute(txh -> {
                                idStore.mutate(partitionKey, KeyColumnValueStore.NO_ADDITIONS, Collections.singletonList(finalTarget), txh);
                                return true;
                            }, new // Use normal consistency level for these non-critical delete operations
                            BackendOperation.TransactionalProvider() {

                                @Override
                                public StoreTransaction openTx() throws BackendException {
                                    return manager.beginTransaction(storeTxConfigBuilder.build());
                                }

                                @Override
                                public void close() {
                                }
                            }, times);
                            break;
                        } catch (BackendException e) {
                            log.warn("Storage exception while deleting old block application - retrying in {}", rollbackWaitTime, e);
                            if (!rollbackWaitTime.isZero())
                                sleepAndConvertInterrupts(rollbackWaitTime);
                        }
                    }
                }
            }
        } catch (UniqueIDExhaustedException e) {
            // No need to increment the backoff wait time or to sleep
            log.warn(e.getMessage());
        } catch (TemporaryBackendException e) {
            backoffMS = Durations.min(backoffMS.multipliedBy(2), idApplicationWaitMS.multipliedBy(32));
            log.warn("Temporary storage exception while acquiring id block - retrying in {}: {}", backoffMS, e);
            sleepAndConvertInterrupts(backoffMS);
        }
    }
    throw new TemporaryLockingException(String.format("Reached timeout %d (%s elapsed) when attempting to allocate id block on partition(%d)-namespace(%d)", timeout.getNano(), methodTime, partition, idNamespace));
}