1. Wrap temporaryStorage in a resource holder, to avoid spurious "Closed"
errors from already-running processing tasks.
2. Exit early from the merging accumulator if the query is cancelled.
* fix ConcurrentModificationException in CachingClusteredClient.run()
* obtain new copy of PartitionHolder to avoid potential multi-threads read/write issue
Refcounting prevents releasing the merge buffer, or closing the concurrent
grouper, before the processing threads have all finished. The better
error handling prevents an avalanche of per-runner exceptions when grouping
resources are exhausted, by grouping those all up into a single merged
exception.
This patch introduces a GroupByStrategy concept and two strategies: "v1"
is the current groupBy strategy and "v2" is a new one. It also introduces
a merge buffers concept in DruidProcessingModule, to try to better
manage memory used for merging.
Both of these are described in more detail in #2987.
There are two goals of this patch:
1. Make it possible for historical/realtime nodes to return larger groupBy
result sets, faster, with better memory management.
2. Make it possible for brokers to merge streams when there are no order-by
columns, avoiding materialization.
This patch does not do anything to help with memory management on the broker
when there are order-by columns or when there are nested queries. That could
potentially be done in a future patch.
* Fix parsing fail of segment id with underscored datasource (Fix for #2786)
* addressed comment
* renamed and moved code into api. added log4 dependency for tests
* addressed comments
* fixed test fails
* Make URI Exctraction Namespace take more sane arguments
* Fixes https://github.com/druid-io/druid/issues/2669
* Update docs
* Rename error message
* Undo overzealous deletion of docs
* Explain caching mechanism a bit more in docs
Geared towards supporting transactional inserts of new segments. This involves an
interface "DataSourceMetadata" that allows combining of partially specified metadata
(useful for partitioned ingestion).
DataSource metadata is stored in a new "dataSource" table.
* Eliminate exclusion groups from pull-deps
* Only consider dependency nodes in pull-deps if they are not in the following scopes
* provided
* test
* system
* Fix a bunch of `<scope>provided</scope>` missing tags
* Better exclusions for a couple of problematic libs
* Defaults the thread priority to java.util.Thread.NORM_PRIORITY in io.druid.indexing.common.task.AbstractTask
* Each exec service has its own Task Factory which is assigned a priority for spawned task. Therefore each priority class has a unique exec service
* Added priority to tasks as taskPriority in the task context. <0 means low, 0 means take default, >0 means high. It is up to any particular implementation to determine how to handle these numbers
* Add options to ForkingTaskRunner
* Add "-XX:+UseThreadPriorities" default option
* Add "-XX:ThreadPriorityPolicy=42" default option
* AbstractTask - Removed unneded @JsonIgnore on priority
* Added priority to RealtimePlumber executors. All sub-executors (non query runners) get Thread.MIN_PRIORITY
* Add persistThreadPriority and mergeThreadPriority to realtime tuning config
- Fix merging when the INTERVALS analysisType is disabled, and add a test.
- Remove transformFn from CombiningSequence, use MappingSequence instead. transformFn did
not work for "accumulate" anyway, which made the tests wrong (the intervals should have
been condensed, but were not).
- Add analysisTypes to the Druids segmentMetadataQuery builder to make testing simpler.
- fixes#1970
- extracted out segment handoff callbacks in SegmentHandoffNotifier
which is responsible for tracking segment handoffs and doing callbacks
when handoff is complete.
- Coordinator now maintains a view of segments in the cluster, this
will affect the jam heap requirements for the overlord for large
clusters.
realtime index task and nodes now use HTTP end points exposed by the
coordinator to get serverView
review comment
fix realtime node guide injection
review comments
make test not rely on scheduled exec
fix compilation
fix import
review comment
introduce immutableSegmentLoadInfo
fix son reading
remove unnecessary logging
This is a feature meant to allow realtime tasks to work without being told upfront
what shardSpec they should use (so we can potentially publish a variable number
of segments per interval).
The idea is that there is a "pendingSegments" table in the metadata store that
tracks allocated segments. Each one has a segment id (the same segment id we know
and love) and is also part of a sequence.
The sequences are an idea from @cheddar that offers a way of doing replication.
If there are N tasks reading exactly the same data with exactly the same logic
(think Kafka tasks reading a fixed range of offsets) then you can place them
in the same sequence, and they will generate the same sequence of segments.