druid/indexing-hadoop/src
Gian Merlino 792e5c58e4
IncrementalIndex#add is no longer thread-safe. (#15697)
* IncrementalIndex#add is no longer thread-safe.

Following #14866, there is no longer a reason for IncrementalIndex#add
to be thread-safe.

It turns out it already was not using its selectors in a thread-safe way,
as exposed by #15615 making `testMultithreadAddFactsUsingExpressionAndJavaScript`
in `IncrementalIndexIngestionTest` flaky. Note that this problem isn't
new: Strings have been stored in the dimension selectors for some time,
but we didn't have a test that checked for that case; we only have
this test that checks for concurrent adds involving numeric selectors.

At any rate, this patch changes OnheapIncrementalIndex to no longer try
to offer a thread-safe "add" method. It also improves performance a bit
by adding a row ID supplier to the selectors it uses to read InputRows,
meaning that it can get the benefit of caching values inside the selectors.

This patch also:

1) Adds synchronization to HyperUniquesAggregator and CardinalityAggregator,
   which the similar datasketches versions already have. This is done to
   help them adhere to the contract of Aggregator: concurrent calls to
   "aggregate" and "get" must be thread-safe.

2) Updates OnHeapIncrementalIndexBenchmark to use JMH and moves it to the
   druid-benchmarks module.

* Spelling.

* Changes from static analysis.

* Fix javadoc.
2024-01-18 03:45:22 -08:00
..
main/java/org/apache/druid/indexer IncrementalIndex#add is no longer thread-safe. (#15697) 2024-01-18 03:45:22 -08:00
test Fix a bug in QosFilter (#14859) 2023-08-21 13:00:41 +05:30