Follow up to #15705
Changes:
- Remove references to ZK-based segment loading in the docs
- Fix doc for existing config `druid.coordinator.loadqueuepeon.http.repeatDelay`
Issue: #14989
The initial step in optimizing segment metadata was to centralize the construction of datasource schema in the Coordinator (#14985). Thereafter, we addressed the problem of publishing schema for realtime segments (#15475). Subsequently, our goal is to eliminate the requirement for regularly executing queries to obtain segment schema information.
This is the final change which involves publishing segment schema for finalized segments from task and periodically polling them in the Coordinator.
The default value for druid.coordinator.kill.period (if unspecified) has changed from P1D to the value of druid.coordinator.period.indexingPeriod. Operators can choose to override druid.coordinator.kill.period and that will take precedence over the default behavior.
The default value for the coordinator dynamic config killTaskSlotRatio is updated from 1.0 to 0.1. This ensures that that kill tasks take up only 1 task slot right out-of-the-box instead of taking up all the task slots.
* Remove stale comment and inline canDutyRun()
* druid.coordinator.kill.period defaults to druid.coordinator.period.indexingPeriod if not set.
- Remove the default P1D value for druid.coordinator.kill.period. Instead default
druid.coordinator.kill.period to whatever value druid.coordinator.period.indexingPeriod is set
to if the former config isn't specified.
- If druid.coordinator.kill.period is set, the value will take precedence over
druid.coordinator.period.indexingPeriod
* Update server/src/test/java/org/apache/druid/server/coordinator/DruidCoordinatorConfigTest.java
* Fix checkstyle error
* Clarify comment
* Update server/src/main/java/org/apache/druid/server/coordinator/DruidCoordinatorConfig.java
* Put back canDutyRun()
* Default killTaskSlotsRatio to 0.1 instead of 1.0 (all slots)
* Fix typo DEFAULT_MAX_COMPACTION_TASK_SLOTS
* Remove unused test method.
* Update default value of killTaskSlotsRatio in docs and web-console default mock
* Move initDuty() after params and config setup.
Starting the process to officially deprecate non SQL compatible modes by updating docs to aggressively call out that Druids non SQL compliant modes are deprecated and will go away someday. There are no code or behavior changes at this PR.
Merging the work so far. @ektravel , @vogievetsky if there are additional improvements, let's track them & make another pr.
* Refactor streaming ingestion docs
* Update property definition
* Update after review
* Update known issues
* Move kinesis and kafka topics to ingestion, add redirects
* Saving changes
* Saving
* Add input format text
* Update after review
* Minor text edit
* Update example syntax
* Revert back to colon
* Fix merge conflicts
* Fix broken links
* Fix spelling error
* Update the group id to org.apache.druid.extensions.contrib for contrib exts.
* Note iceberg and delta lake extensions in extensions.md
* properties and shell backticks
* Update groupId in distribution/pom.xml
* remove delta-lake from dist.
* Add note on downloading extension.
* New: Add DDSketch-Druid extension
- Based off of http://www.vldb.org/pvldb/vol12/p2195-masson.pdf and uses
the corresponding https://github.com/DataDog/sketches-java library
- contains tests for post building and using aggregation/post
aggregation.
- New aggregator: `ddSketch`
- New post aggregators: `quantileFromDDSketch` and
`quantilesFromDDSketch`
* Fixing easy CodeQL warnings/errors
* Fixing docs, and dependencies
Also moved aggregator ids to AggregatorUtil and PostAggregatorIds
* Adding more Docs and better null/empty handling for aggregators
* Fixing docs, and pom version
* DDSketch documentation format and wording
* Add SpectatorHistogram extension
* Clarify documentation
Cleanup comments
* Use ColumnValueSelector directly
so that we support being queried as a Number using longSum or doubleSum aggregators as well as a histogram.
When queried as a Number, we're returning the count of entries in the histogram.
* Apply suggestions from code review
Co-authored-by: Victoria Lim <vtlim@users.noreply.github.com>
* Fix references
* Fix spelling
* Update docs/development/extensions-contrib/spectator-histogram.md
Co-authored-by: Victoria Lim <vtlim@users.noreply.github.com>
---------
Co-authored-by: Victoria Lim <vtlim@users.noreply.github.com>
This PR enables the flag by default to queue excess query requests in the jetty queue. Still keeping the flag so that it can be turned off if necessary. But the flag will be removed in the future.
In the current design, brokers query both data nodes and tasks to fetch the schema of the segments they serve. The table schema is then constructed by combining the schemas of all segments within a datasource. However, this approach leads to a high number of segment metadata queries during broker startup, resulting in slow startup times and various issues outlined in the design proposal.
To address these challenges, we propose centralizing the table schema management process within the coordinator. This change is the first step in that direction. In the new arrangement, the coordinator will take on the responsibility of querying both data nodes and tasks to fetch segment schema and subsequently building the table schema. Brokers will now simply query the Coordinator to fetch table schema. Importantly, brokers will still retain the capability to build table schemas if the need arises, ensuring both flexibility and resilience.
* sql compatible tri-state native logical filters when druid.expressions.useStrictBooleans=true and druid.generic.useDefaultValueForNull=false, and new druid.generic.useThreeValueLogicForNativeFilters=true
* log.warn if non-default configurations are used to guide operators towards SQL complaint behavior
This PR updates the library used for Memcached client to AWS Elasticache Client : https://github.com/awslabs/aws-elasticache-cluster-client-memcached-for-java
This enables us to use the option of encrypting data in transit:
Amazon ElastiCache for Memcached now supports encryption of data in transit
For clusters running the Memcached engine, ElastiCache supports Auto Discovery—the ability for client programs to automatically identify all of the nodes in a cache cluster, and to initiate and maintain connections to all of these nodes.
Benefits of Auto Discovery - Amazon ElastiCache
AWS has forked spymemcached 2.12.1, and has since added all the patches included in 2.12.2 and 2.12.3 as part of the 1.2.0 release. So, this can now be considered as an equivalent drop-in replacement.
GitHub - awslabs/aws-elasticache-cluster-client-memcached-for-java: Amazon ElastiCache Cluster Client for Java - enhanced library to connect to ElastiCache clusters.
https://docs.aws.amazon.com/AWSJavaSDK/latest/javadoc/com/amazonaws/services/elasticache/AmazonElastiCacheClient.html#AmazonElastiCacheClient--
How to enable TLS with Elasticache
On server side:
https://docs.aws.amazon.com/AmazonElastiCache/latest/mem-ug/in-transit-encryption-mc.html#in-transit-encryption-enable-existing-mc
On client side:
GitHub - awslabs/aws-elasticache-cluster-client-memcached-for-java: Amazon ElastiCache Cluster Client for Java - enhanced library to connect to ElastiCache clusters.
A new monitor SubqueryCountStatsMonitor which emits the metrics corresponding to the subqueries and their execution is now introduced. Moreover, the user can now also use the auto mode to automatically set the number of bytes available per query for the inlining of its subquery's results.
Changes:
[A] Remove config `decommissioningMaxPercentOfMaxSegmentsToMove`
- It is a complicated config 😅 ,
- It is always desirable to prioritize move from decommissioning servers so that
they can be terminated quickly, so this should always be 100%
- It is already handled by `smartSegmentLoading` (enabled by default)
[B] Remove config `maxNonPrimaryReplicantsToLoad`
This was added in #11135 to address two requirements:
- Prevent coordinator runs from getting stuck assigning too many segments to historicals
- Prevent load of replicas from competing with load of unavailable segments
Both of these requirements are now already met thanks to:
- Round-robin segment assignment
- Prioritization in the new coordinator
- Modifications to `replicationThrottleLimit`
- `smartSegmentLoading` (enabled by default)
Changes
- Increase value of `replicationThrottleLimit` computed by `smartSegmentLoading` from
2% to 5% of total number of used segments.
- Assign replicas to a tier even when some replicas are already being loaded in that tier
- Limit the total number of replicas in load queue at start of run + replica assignments in
the run to the `replicationThrottleLimit`.
i.e. for every tier,
num loading replicas at start of run + num replicas assigned in run <= replicationThrottleLimit
Changes:
- Determine the default value of balancerComputeThreads based on number of
coordinator cpus rather than number of segments. Even if the number of segments
is low and we create more balancer threads, it doesn't hurt the system as threads
would mostly be idle.
- Remove unused field from SegmentLoadQueueManager
Expected values:
- Clusters with ~1M segments typically work with Coordinators having 16 cores or more.
This would give us 8 balancer threads, which is the same as the current maximum.
- On small clusters, even a single thread is enough to do the required balancing work.
### Description
This change enables the `KillUnusedSegments` coordinator duty to be scheduled continuously. Things that prevented this, or made this difficult before were the following:
1. If scheduled at fast enough rate, the duty would find the same intervals to kill for the same datasources, while kill tasks submitted for those same datasources and intervals were already underway, thus wasting task slots on duplicated work.
2. The task resources used by auto kill were previously unbounded. Each duty run period, if unused
segments were found for any datasource, a kill task would be submitted to kill them.
This pr solves for both of these issues:
1. The duty keeps track of the end time of the last interval found when killing unused segments for each datasource, in a in memory map. The end time for each datasource, if found, is used as the start time lower bound, when searching for unused intervals for that same datasource. Each duty run, we remove any datasource keys from this map that are no longer found to match datasources in the system, or in whitelist, and also remove a datasource entry, if there is found to be no unused segments for the datasource, which happens when we fail to find an interval which includes unused segments. Removing the datasource entry from the map, allows for searching for unusedSegments in the datasource from the beginning of time once again
2. The unbounded task resource usage can be mitigated with coordinator dynamic config added as part of ba957a9b97
Operators can configure continous auto kill by providing coordinator runtime properties similar to the following:
```
druid.coordinator.period.indexingPeriod=PT60S
druid.coordinator.kill.period=PT60S
```
And providing sensible limits to the killTask usage via coordinator dynamic properties.
* Add new configurable buffer period to create gap between mark unused and kill of segment
* Changes after testing
* fixes and improvements
* changes after initial self review
* self review changes
* update sql statement that was lacking last_used
* shore up some code in SqlMetadataConnector after self review
* fix derby compatibility and improve testing/docs
* fix checkstyle violations
* Fixes post merge with master
* add some unit tests to improve coverage
* ignore test coverage on new UpdateTools cli tool
* another attempt to ignore UpdateTables in coverage check
* change column name to used_flag_last_updated
* fix a method signature after column name switch
* update docs spelling
* Update spelling dictionary
* Fixing up docs/spelling and integrating altering tasks table with my alteration code
* Update NULL values for used_flag_last_updated in the background
* Remove logic to allow segs with null used_flag_last_updated to be killed regardless of bufferPeriod
* remove unneeded things now that the new column is automatically updated
* Test new background row updater method
* fix broken tests
* fix create table statement
* cleanup DDL formatting
* Revert adding columns to entry table by default
* fix compilation issues after merge with master
* discovered and fixed metastore inserts that were breaking integration tests
* fixup forgotten insert by using pattern of sharing now timestamp across columns
* fix issue introduced by merge
* fixup after merge with master
* add some directions to docs in the case of segment table validation issues
### Description
Previously, the `KillUnusedSegments` coordinator duty, in charge of periodically deleting unused segments, could spawn an unlimited number of kill tasks for unused segments. This change adds 2 new coordinator dynamic configs that can be used to control the limit of tasks spawned by this coordinator duty
`killTaskSlotRatio`: Ratio of total available task slots, including autoscaling if applicable that will be allowed for kill tasks. This limit only applies for kill tasks that are spawned automatically by the coordinator's auto kill duty. Default is 1, which allows all available tasks to be used, which is the existing behavior
`maxKillTaskSlots`: Maximum number of tasks that will be allowed for kill tasks. This limit only applies for kill tasks that are spawned automatically by the coordinator's auto kill duty. Default is INT.MAX, which essentially allows for unbounded number of tasks, which is the existing behavior.
Realize that we can effectively get away with just the one `killTaskSlotRatio`, but following similarly to the compaction config, which has similar properties; I thought it was good to have some control of the upper limit regardless of ratio provided.
#### Release note
NEW: `killTaskSlotRatio` and `maxKillTaskSlots` coordinator dynamic config properties added that allow control of task resource usage spawned by `KillUnusedSegments` coordinator task (auto kill)
Cache is disabled for GroupByStrategyV2 on broker since the pr #3820 [groupBy v2: Results not fully merged when caching is enabled on the broker]. But we can enable the result-level cache on broker for GroupByStrategyV2 and keep the segment-level cache disabled.
* Claim full support for Java 17.
No production code has changed, except the startup scripts.
Changes:
1) Allow Java 17 without DRUID_SKIP_JAVA_CHECK.
2) Include the full list of opens and exports on both Java 11 and 17.
3) Document that Java 17 is both supported and preferred.
4) Switch some tests from Java 11 to 17 to get better coverage on the
preferred version.
* Doc update.
* Update errorprone.
* Update docker_build_containers.sh.
* Update errorprone in licenses.yaml.
* Add some more run-javas.
* Additional run-javas.
* Update errorprone.
* Suppress new errorprone error.
* Add exports and opens in ForkingTaskRunner for Java 11+.
Test, doc changes.
* Additional errorprone updates.
* Update for errorprone.
* Restore old fomatting in LdapCredentialsValidator.
* Copy bin/ too.
* Fix Java 15, 17 build line in docker_build_containers.sh.
* Update busybox image.
* One more java command.
* Fix interpolation.
* IT commandline refinements.
* Switch to busybox 1.34.1-glibc.
* POM adjustments, build and test one IT on 17.
* Additional debugging.
* Fix silly thing.
* Adjust command line.
* Add exports and opens one more place.
* Additional harmonization of strong encapsulation parameters.
After #13197 , several coordinator configs are now redundant as they are not being
used anymore, neither with `smartSegmentLoading` nor otherwise.
Changes:
- Remove dynamic configs `emitBalancingStats`: balancer error stats are always
emitted, debug stats can be logged by using `debugDimensions`
- `useBatchedSegmentSampler`, `percentOfSegmentsToConsiderPerMove`:
batched segment sampling is always used
- Add test to verify deserialization with unknown properties
- Update `CoordinatorRunStats` to always track stats, this can be optimized later.
* combine string column implementations
changes:
* generic indexed, front-coded, and auto string columns now all share the same column and index supplier implementations
* remove CachingIndexed implementation, which I think is largely no longer needed by the switch of many things to directly using ByteBuffer, avoiding the cost of creating Strings
* remove ColumnConfig.columnCacheSizeBytes since CachingIndexed was the only user
* Add OverlordStatusMonitor and CoordinatorStatusMonitor to monitor service leader status
* make the monitor more general
* resolve conflict
* use Supplier pattern to provide metrics
* reformat code and doc
* move service specific tag to dimension
* minor refine
* update doc
* reformat code
* address comments
* remove declared exception
* bind HeartbeatSupplier conditionally in Coordinator
Users can now add a guardrail to prevent subquery’s results from exceeding the set number of bytes by setting druid.server.http.maxSubqueryRows in Broker's config or maxSubqueryRows in the query context. This feature is experimental for now and would default back to row-based limiting in case it fails to get the accurate size of the results consumed by the query.
Alberic Liu
Rishabh Singh
Kashif Faraz
Abhishek Radhakrishnan
Sergio Ferragut
Jill Osborne
Gian Merlino
Clint Wylie
Katya Macedo
Abhishek Agarwal
Hiroshi Fukada
Ben Sykes
Tts-233
David Christle
Laksh Singla
Parth Agrawal
zachjsh
Lucas Capistrant
317brian
Tejaswini Bandlamudi
cristian-popa
hqx871
Nhi Pham
YongGang