Examples with ChainedExecutionQueryRunner org.apache.druid.query.ChainedExecutionQueryRunner used on opensource projects

Example 1 with ChainedExecutionQueryRunner

use of org.apache.druid.query.ChainedExecutionQueryRunner in project druid by druid-io.

the class GroupByMergingQueryRunnerV2 method run.

@Override
public Sequence<ResultRow> run(final QueryPlus<ResultRow> queryPlus, final ResponseContext responseContext) {
    final GroupByQuery query = (GroupByQuery) queryPlus.getQuery();
    final GroupByQueryConfig querySpecificConfig = config.withOverrides(query);
    // CTX_KEY_MERGE_RUNNERS_USING_CHAINED_EXECUTION is here because realtime servers use nested mergeRunners calls
    // (one for the entire query and one for each sink). We only want the outer call to actually do merging with a
    // merge buffer, otherwise the query will allocate too many merge buffers. This is potentially sub-optimal as it
    // will involve materializing the results for each sink before starting to feed them into the outer merge buffer.
    // I'm not sure of a better way to do this without tweaking how realtime servers do queries.
    final boolean forceChainedExecution = query.getContextBoolean(CTX_KEY_MERGE_RUNNERS_USING_CHAINED_EXECUTION, false);
    final QueryPlus<ResultRow> queryPlusForRunners = queryPlus.withQuery(query.withOverriddenContext(ImmutableMap.of(CTX_KEY_MERGE_RUNNERS_USING_CHAINED_EXECUTION, true))).withoutThreadUnsafeState();
    if (QueryContexts.isBySegment(query) || forceChainedExecution) {
        ChainedExecutionQueryRunner<ResultRow> runner = new ChainedExecutionQueryRunner<>(queryProcessingPool, queryWatcher, queryables);
        return runner.run(queryPlusForRunners, responseContext);
    }
    final boolean isSingleThreaded = querySpecificConfig.isSingleThreaded();
    final File temporaryStorageDirectory = new File(processingTmpDir, StringUtils.format("druid-groupBy-%s_%s", UUID.randomUUID(), query.getId()));
    final int priority = QueryContexts.getPriority(query);
    // Figure out timeoutAt time now, so we can apply the timeout to both the mergeBufferPool.take and the actual
    // query processing together.
    final long queryTimeout = QueryContexts.getTimeout(query);
    final boolean hasTimeout = QueryContexts.hasTimeout(query);
    final long timeoutAt = System.currentTimeMillis() + queryTimeout;
    return new BaseSequence<>(new BaseSequence.IteratorMaker<ResultRow, CloseableGrouperIterator<RowBasedKey, ResultRow>>() {

        @Override
        public CloseableGrouperIterator<RowBasedKey, ResultRow> make() {
            final Closer resources = Closer.create();
            try {
                final LimitedTemporaryStorage temporaryStorage = new LimitedTemporaryStorage(temporaryStorageDirectory, querySpecificConfig.getMaxOnDiskStorage());
                final ReferenceCountingResourceHolder<LimitedTemporaryStorage> temporaryStorageHolder = ReferenceCountingResourceHolder.fromCloseable(temporaryStorage);
                resources.register(temporaryStorageHolder);
                // If parallelCombine is enabled, we need two merge buffers for parallel aggregating and parallel combining
                final int numMergeBuffers = querySpecificConfig.getNumParallelCombineThreads() > 1 ? 2 : 1;
                final List<ReferenceCountingResourceHolder<ByteBuffer>> mergeBufferHolders = getMergeBuffersHolder(numMergeBuffers, hasTimeout, timeoutAt);
                resources.registerAll(mergeBufferHolders);
                final ReferenceCountingResourceHolder<ByteBuffer> mergeBufferHolder = mergeBufferHolders.get(0);
                final ReferenceCountingResourceHolder<ByteBuffer> combineBufferHolder = numMergeBuffers == 2 ? mergeBufferHolders.get(1) : null;
                Pair<Grouper<RowBasedKey>, Accumulator<AggregateResult, ResultRow>> pair = RowBasedGrouperHelper.createGrouperAccumulatorPair(query, null, config, Suppliers.ofInstance(mergeBufferHolder.get()), combineBufferHolder, concurrencyHint, temporaryStorage, spillMapper, // Passed as executor service
                queryProcessingPool, priority, hasTimeout, timeoutAt, mergeBufferSize);
                final Grouper<RowBasedKey> grouper = pair.lhs;
                final Accumulator<AggregateResult, ResultRow> accumulator = pair.rhs;
                grouper.init();
                final ReferenceCountingResourceHolder<Grouper<RowBasedKey>> grouperHolder = ReferenceCountingResourceHolder.fromCloseable(grouper);
                resources.register(grouperHolder);
                List<ListenableFuture<AggregateResult>> futures = Lists.newArrayList(Iterables.transform(queryables, new Function<QueryRunner<ResultRow>, ListenableFuture<AggregateResult>>() {

                    @Override
                    public ListenableFuture<AggregateResult> apply(final QueryRunner<ResultRow> input) {
                        if (input == null) {
                            throw new ISE("Null queryRunner! Looks to be some segment unmapping action happening");
                        }
                        ListenableFuture<AggregateResult> future = queryProcessingPool.submitRunnerTask(new AbstractPrioritizedQueryRunnerCallable<AggregateResult, ResultRow>(priority, input) {

                            @Override
                            public AggregateResult call() {
                                try (// These variables are used to close releasers automatically.
                                @SuppressWarnings("unused") Releaser bufferReleaser = mergeBufferHolder.increment();
                                    @SuppressWarnings("unused") Releaser grouperReleaser = grouperHolder.increment()) {
                                    // Return true if OK, false if resources were exhausted.
                                    return input.run(queryPlusForRunners, responseContext).accumulate(AggregateResult.ok(), accumulator);
                                } catch (QueryInterruptedException | QueryTimeoutException e) {
                                    throw e;
                                } catch (Exception e) {
                                    log.error(e, "Exception with one of the sequences!");
                                    throw new RuntimeException(e);
                                }
                            }
                        });
                        if (isSingleThreaded) {
                            waitForFutureCompletion(query, ImmutableList.of(future), hasTimeout, timeoutAt - System.currentTimeMillis());
                        }
                        return future;
                    }
                }));
                if (!isSingleThreaded) {
                    waitForFutureCompletion(query, futures, hasTimeout, timeoutAt - System.currentTimeMillis());
                }
                return RowBasedGrouperHelper.makeGrouperIterator(grouper, query, resources);
            } catch (Throwable t) {
                // Exception caught while setting up the iterator; release resources.
                try {
                    resources.close();
                } catch (Exception ex) {
                    t.addSuppressed(ex);
                }
                throw t;
            }
        }

        @Override
        public void cleanup(CloseableGrouperIterator<RowBasedKey, ResultRow> iterFromMake) {
            iterFromMake.close();
        }
    });
}

Example 2 with ChainedExecutionQueryRunner

use of org.apache.druid.query.ChainedExecutionQueryRunner in project druid by druid-io.

the class GroupByQueryRunnerTest method testTypeConversionWithMergingChainedExecutionRunner.

@Test
public void testTypeConversionWithMergingChainedExecutionRunner() {
    // Cannot vectorize due to extraction dimension spec.
    cannotVectorize();
    if (config.getDefaultStrategy().equals(GroupByStrategySelector.STRATEGY_V1)) {
        expectedException.expect(UnsupportedOperationException.class);
        expectedException.expectMessage("GroupBy v1 only supports dimensions with an outputType of STRING.");
    }
    GroupByQuery query = makeQueryBuilder().setDataSource(QueryRunnerTestHelper.DATA_SOURCE).setQuerySegmentSpec(QueryRunnerTestHelper.FIRST_TO_THIRD).setDimensions(new DefaultDimensionSpec("quality", "alias"), new ExtractionDimensionSpec("quality", "qualityLen", ColumnType.LONG, StrlenExtractionFn.instance())).setDimFilter(new SelectorDimFilter("quality", "technology", null)).setAggregatorSpecs(QueryRunnerTestHelper.ROWS_COUNT, new LongSumAggregatorFactory("idx", "index")).setGranularity(QueryRunnerTestHelper.DAY_GRAN).build();
    List<ResultRow> expectedResults = Arrays.asList(makeRow(query, "2011-04-01", "alias", "technology", "qualityLen", 10L, "rows", 2L, "idx", 156L), makeRow(query, "2011-04-02", "alias", "technology", "qualityLen", 10L, "rows", 2L, "idx", 194L));
    ChainedExecutionQueryRunner ceqr = new ChainedExecutionQueryRunner(DirectQueryProcessingPool.INSTANCE, (query1, future) -> {
        return;
    }, ImmutableList.of(runner, runner));
    QueryRunner<ResultRow> mergingRunner = factory.mergeRunners(Execs.directExecutor(), ImmutableList.of(ceqr));
    Iterable<ResultRow> results = GroupByQueryRunnerTestHelper.runQuery(factory, mergingRunner, query);
    TestHelper.assertExpectedObjects(expectedResults, results, "type-conversion");
}