During ingestion, incremental segments are created in memory for the different time chunks and persisted to disk when certain thresholds are reached (max number of rows, max memory, incremental persist period etc). In the case where there are a lot of dimension and metrics (1000+) it was observed that the creation/serialization of incremental segment file format for persistence and persisting the file took a while and it was blocking ingestion of new data. This affected the real-time ingestion. This serialization and persistence can be parallelized across the different time chunks. This update aims to do that.
The patch adds a simple configuration parameter to the ingestion tuning configuration to specify number of persistence threads. The default value is 1 if it not specified which makes it the same as it is today.
Proposal #13469
Original PR #14024
A new method is being added in QueryLifecycle class to authorise a query based on authentication result.
This method is required since we authenticate the query by intercepting it in the grpc extension and pass down the authentication result.
### Description
The unusedSegment api response was extended to include the original DataSegment object with the creation time and last used update time added to it. A new object `DataSegmentPlus` was created for this purpose, and the metadata queries used were updated as needed.
example response:
```
[
{
"dataSegment": {
"dataSource": "inline_data",
"interval": "2023-01-02T00:00:00.000Z/2023-01-03T00:00:00.000Z",
"version": "2024-01-25T16:06:42.835Z",
"loadSpec": {
"type": "local",
"path": "/Users/zachsherman/projects/opensrc-druid/distribution/target/apache-druid-30.0.0-SNAPSHOT/var/druid/segments/inline_data/2023-01-02T00:00:00.000Z_2023-01-03T00:00:00.000Z/2024-01-25T16:06:42.835Z/0/index/"
},
"dimensions": "str_dim,double_measure1,double_measure2",
"metrics": "",
"shardSpec": {
"type": "numbered",
"partitionNum": 0,
"partitions": 1
},
"binaryVersion": 9,
"size": 1402,
"identifier": "inline_data_2023-01-02T00:00:00.000Z_2023-01-03T00:00:00.000Z_2024-01-25T16:06:42.835Z"
},
"createdDate": "2024-01-25T16:06:44.196Z",
"usedStatusLastUpdatedDate": "2024-01-25T16:07:34.909Z"
}
]
```
* Merge hydrant runners flatly for realtime queries.
Prior to this patch, we have two layers of mergeRunners for realtime
queries: one for each Sink (a logical segment) and one across all
Sinks. This is done because to keep metrics and results grouped by Sink,
given that each FireHydrant within a Sink has its own separate storage
adapter.
However, it costs extra memory usage due to the extra layer of
materialization. This is especially pronounced for groupBy queries,
which only use their merge buffers at the top layer of merging. The
lower layer of merging materializes ResultRows directly into the heap,
which can cause heap exhaustion if there are enough ResultRows.
This patch changes to a single layer of merging when bySegment: false,
just like Historicals. To accommodate that, segment metrics like
query/segment/time are now per-FireHydrant instead of per-Sink.
Two layers of merging are retained when bySegment: true. This isn't
common, because it's typically only used when segment level caching
is enabled on the Broker, which is off by default.
* Use SinkQueryRunners.
* Remove unused method.
* Kill tasks should honor the buffer period of unused segments.
- The coordinator duty KillUnusedSegments determines an umbrella interval
for each datasource to determine the kill interval. There can be multiple unused
segments in an umbrella interval with different used_status_last_updated timestamps.
For example, consider an unused segment that is 30 days old and one that is 1 hour old. Currently
the kill task after the 30-day mark would kill both the unused segments and not retain the 1-hour
old one.
- However, when a kill task is instantiated with this umbrella interval, it’d kill
all the unused segments regardless of the last updated timestamp. We need kill
tasks and RetrieveUnusedSegmentsAction to honor the bufferPeriod to avoid killing
unused segments in the kill interval prematurely.
* Clarify default behavior in docs.
* test comments
* fix canDutyRun()
* small updates.
* checkstyle
* forbidden api fix
* doc fix, unused import, codeql scan error, and cleanup logs.
* Address review comments
* Rename maxUsedFlagLastUpdatedTime to maxUsedStatusLastUpdatedTime
This is consistent with the column name `used_status_last_updated`.
* Apply suggestions from code review
Co-authored-by: Kashif Faraz <kashif.faraz@gmail.com>
* Make period Duration type
* Remove older variants of runKilLTask() in OverlordClient interface
* Test can now run without waiting for canDutyRun().
* Remove previous variants of retrieveUnusedSegments from internal metadata storage coordinator interface.
Removes the following interface methods in favor of a new method added:
- retrieveUnusedSegmentsForInterval(String, Interval)
- retrieveUnusedSegmentsForInterval(String, Interval, Integer)
* Chain stream operations
* cleanup
* Pass in the lastUpdatedTime to markUnused test function and remove sleep.
---------
Co-authored-by: Kashif Faraz <kashif.faraz@gmail.com>
* Reverse, pull up lookups in the SQL planner.
Adds two new rules:
1) ReverseLookupRule, which eliminates calls to LOOKUP by doing
reverse lookups.
2) AggregatePullUpLookupRule, which pulls up calls to LOOKUP above
GROUP BY, when the lookup is injective.
Adds configs `sqlReverseLookup` and `sqlPullUpLookup` to control whether
these rules fire. Both are enabled by default.
To minimize the chance of performance problems due to many keys mapping to
the same value, ReverseLookupRule refrains from reversing a lookup if there
are more keys than `inSubQueryThreshold`. The rationale for using this setting
is that reversal works by generating an IN, and the `inSubQueryThreshold`
describes the largest IN the user wants the planner to create.
* Add additional line.
* Style.
* Remove commented-out lines.
* Fix tests.
* Add test.
* Fix doc link.
* Fix docs.
* Add one more test.
* Fix tests.
* Logic, test updates.
* - Make FilterDecomposeConcatRule more flexible.
- Make CalciteRulesManager apply reduction rules til fixpoint.
* Additional tests, simplify code.
Currently, If 2 tasks are consuming from the same partitions, try to publish the segment and update the metadata, the second task can fail because the end offset stored in the metadata store doesn't match with the start offset of the second task. We can fix this by retrying instead of failing.
AFAIK apart from the above issue, the metadata mismatch can happen in 2 scenarios:
- when we update the input topic name for the data source
- when we run 2 replicas of ingestion tasks(1 replica will publish and 1 will fail as the first replica has already updated the metadata).
Implemented the comparable function to compare the last committed end offset and new Sequence start offset. And return a specific error msg for this.
Add retry logic on indexers to retry for this specific error msg.
Updated the existing test case.
The initial step in optimizing segment metadata was to centralize the construction of datasource schema in the Coordinator (#14985). Subsequently, our goal is to eliminate the requirement for regularly executing queries to obtain segment schema information. This task encompasses addressing both realtime and finalized segments.
This modification specifically addresses the issue with realtime segments. Tasks will now routinely communicate the schema for realtime segments during the segment announcement process. The Coordinator will identify the schema alongside the segment announcement and subsequently update the schema for realtime segments in the metadata cache.
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.
* Allow overwriting ServerConnector accept queue size
* Use a single config
* Fix spacing
* fix spacing
* fixed value
* read value from environment
* fix spacing
* Unpack value before reading
* check somaxconn on linux only
* Reverse lookup fixes and enhancements.
1) Add a "mayIncludeUnknown" parameter to DimFilter#optimize. This is important
because otherwise the reverse-lookup optimization is done improperly when
the "in" filter appears under a "not", and the lookup extractionFn may return
null for some possible values of the filtered column. The "includeUnknown" test
cases in InDimFilterTest illustrate the difference in behavior.
2) Enhance InDimFilter#optimizeLookup to handle "mayIncludeUnknown", and to be able
to do a reverse lookup in a wider variety of cases.
3) Make "unapply" protected in LookupExtractor, and move callers to "unapplyAll".
The main reason is that MapLookupExtractor, a common implementation, lacks a
reverse mapping and therefore does a scan of the map for each call to "unapply".
For performance sake these calls need to be batched.
* Remove optimize call from BloomDimFilter.
* Follow the law.
* Fix tests.
* Fix imports.
* Switch function.
* Fix tests.
* More tests.
* Minor fixes
* Update docs/development/extensions-contrib/prometheus.md
Co-authored-by: Charles Smith <techdocsmith@gmail.com>
---------
Co-authored-by: Charles Smith <techdocsmith@gmail.com>
Currently in the realtime ingestion (Kafka/Kinesis) case, after publishing the segments, upon acknowledgement from the coordinator that the segments are already placed in some historicals, the peon would unannounce the segments (basically saying the segments are not in this peon anymore to the whole cluster) and drop the segments from cache and sink timeline in one shot.
The in transit queries from the brokers that still thinks the segments are in the peon can get a NullPointer exception when the peon is unsetting the hydrants in the sinks.
The fix would let the peon to wait for a configurable delay period before dropping segments, remove segments from cache etc after the peon unannounce the segments.
This delayed approach is similar to how the historicals handle segments moving out.
Changes
- Add `log` implementation for `AuditManager` alongwith `SQLAuditManager`
- `LoggingAuditManager` simply logs the audit event. Thus, it returns empty for
all `fetchAuditHistory` calls.
- Add new config `druid.audit.manager.type` which can take values `log`, `sql` (default)
- Add new config `druid.audit.manager.logLevel` which can take values `DEBUG`, `INFO`, `WARN`.
This gets activated only if `type` is `log`.
- Remove usage of `ConfigSerde` from `AuditManager` as audit is not just limited to configs
- Add `AuditSerdeHelper` for a single implementation of serialization/deserialization of
audit payload and other utility methods.
The segment allocation algorithm reuses an already allocated pending segment if the new allocation request is made for the same parameters:
datasource
sequence name
same interval
same value of skipSegmentLineageCheck (false for batch append, true for streaming append)
same previous segment id (used only when skipSegmentLineageCheck = false)
The above parameters can thus uniquely identify a pending segment (enforced by the UNIQUE constraint on the sequence_name_prev_id_sha1 column in druid_pendingSegments metadata table).
This reuse is done in order to
allow replica tasks (in case of streaming ingestion) to use the same set of segment IDs.
allow re-run of a failed batch task to use the same segment ID and prevent unnecessary allocations
This PR builds on #13304 to skip compaction for datasources with segments that have their interval start or end coinciding with Eternity interval end-points.
This is needed in order to prevent an issue similar to #13208 as the Coordinator tries to iterate over a large number of intervals when trying to compact an interval with infinite start or end.
### Description
This pr adds an api for retrieving unused segments for a particular datasource. The api supports pagination by the addition of `limit` and `lastSegmentId` parameters. The resulting unused segments are returned with optional `sortOrder`, `ASC` or `DESC` with respect to the matching segments `id`, `start time`, and `end time`, or not returned in any guarenteed order if `sortOrder` is not specified
`GET /druid/coordinator/v1/datasources/{dataSourceName}/unusedSegments?interval={interval}&limit={limit}&lastSegmentId={lastSegmentId}&sortOrder={sortOrder}`
Returns a list of unused segments for a datasource in the cluster contained within an optionally specified interval.
Optional parameters for limit and lastSegmentId can be given as well, to limit results and enable paginated results.
The results may be sorted in either ASC, or DESC order depending on specifying the sortOrder parameter.
`dataSourceName`: The name of the datasource
`interval`: the specific interval to search for unused segments for.
`limit`: the maximum number of unused segments to return information about. This property helps to
support pagination
`lastSegmentId`: the last segment id from which to search for results. All segments returned are > this segment
lexigraphically if sortOrder is null or ASC, or < this segment lexigraphically if sortOrder is DESC.
`sortOrder`: Specifies the order with which to return the matching segments by start time, end time. A null
value indicates that order does not matter.
This PR has:
- [x] been self-reviewed.
- [ ] using the [concurrency checklist](https://github.com/apache/druid/blob/master/dev/code-review/concurrency.md) (Remove this item if the PR doesn't have any relation to concurrency.)
- [x] added documentation for new or modified features or behaviors.
- [ ] a release note entry in the PR description.
- [x] added Javadocs for most classes and all non-trivial methods. Linked related entities via Javadoc links.
- [ ] added or updated version, license, or notice information in [licenses.yaml](https://github.com/apache/druid/blob/master/dev/license.md)
- [x] added comments explaining the "why" and the intent of the code wherever would not be obvious for an unfamiliar reader.
- [x] added unit tests or modified existing tests to cover new code paths, ensuring the threshold for [code coverage](https://github.com/apache/druid/blob/master/dev/code-review/code-coverage.md) is met.
- [ ] added integration tests.
- [x] been tested in a test Druid cluster.
* Add initial draft of MarkDanglingTombstonesAsUnused duty.
* Use overshadowed segments instead of all used segments.
* Add unit test for MarkDanglingSegmentsAsUnused duty.
* Add mock call
* Simplify code.
* Docs
* shorter lines formatting
* metric doc
* More tests, refactor and fix up some logic.
* update javadocs; other review comments.
* Make numCorePartitions as 0 in the TombstoneShardSpec.
* fix up test
* Add tombstone core partition tests
* Update docs/design/coordinator.md
Co-authored-by: 317brian <53799971+317brian@users.noreply.github.com>
* review comment
* Minor cleanup
* Only consider tombstones with 0 core partitions
* Need to register the test shard type to make jackson happy
* test comments
* checkstyle
* fixup misc typos in comments
* Update logic to use overshadowed segments
* minor cleanup
* Rename duty to eternity tombstone instead of dangling. Add test for full eternity tombstone.
* Address review feedback.
---------
Co-authored-by: 317brian <53799971+317brian@users.noreply.github.com>
Description
With CentralizedDatasourceSchema (#14989) feature enabled, metadata for appended segments was not being refreshed. This caused numRows to be 0 for the new segments and would probably cause the datasource schema to not include columns from the new segments.
Analysis
The problem turned out in the new QuerySegmentWalker implementation in the Coordinator. It first finds the segment to be queried in the Coordinator timeline. Then it creates a new timeline of the segments present in the timeline.
The problem was that it is looking up complete partition set in the new timeline. Since the appended segments by themselves do not make a complete partition set, no SegmentMetadataQuery were executed.
Update guava to 32.0.1-jre to address two CVEs: CVE-2020-8908, CVE-2023-2976
This change requires a minor test change to remove assumptions about ordering.
---------
Co-authored-by: Xavier Léauté <xl+github@xvrl.net>
* Fixing failing compaction/parallel index jobs during upgrade due to new actions not available on the overlord.
* Fixing build
* Removing extra space.
* Fixing json getter.
* Review comments.
* Fix NPE caused by realtime segment closing race, fix possible missing-segment retry bug.
Fixes#12168, by returning empty from FireHydrant when the segment is
swapped to null. This causes the SinkQuerySegmentWalker to use
ReportTimelineMissingSegmentQueryRunner, which causes the Broker to look
for the segment somewhere else.
In addition, this patch changes SinkQuerySegmentWalker to acquire references
to all hydrants (subsegments of a sink) at once, and return a
ReportTimelineMissingSegmentQueryRunner if *any* of them could not be acquired.
I suspect, although have not confirmed, that the prior behavior could lead to
segments being reported as missing even though results from some hydrants were
still included.
* Some more test coverage.
* Make numCorePartitions as 0 in the TombstoneShardSpec.
* fix up test
* Add tombstone core partition tests
* review comment
* Need to register the test shard type to make jackson happy
In pull request #14985, a bug was introduced where periodic refresh would skip rebuilding a datasource's schema after encountering a non-existent datasource. This resulted in remaining datasources having stale schema information.
This change addresses the bug and adds a unit test to validate the refresh mechanism's behaviour when a datasource is removed, and other datasources have schema changes.
* Add a unit test that fails when used segments with too many intervals are retrieved.
- This is a failing test case that needs to be ignored.
* Batch the intervals (use 100 as it's consistent with batching in other places).
* move the filtering inside the batch
* Account for limit cross the batch splits.
* Adjustments
* Fixup and add tests
* small refactor
* add more tests.
* remove wrapper.
* Minor edits
* assert out of range
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.
* Use filters for pruning properly for hash-joins.
Native used them too aggressively: it might use filters for the RHS
to prune the LHS. MSQ used them not at all. Now, both use them properly,
pruning based on base (LHS) columns only.
* Fix tests.
* Fix style.
* Clear filterFields too.
* Update.
* Add system fields to input sources.
Main changes:
1) The SystemField enum defines system fields "__file_uri", "__file_path",
and "__file_bucket". They are associated with each input entity.
2) The SystemFieldInputSource interface can be added to any InputSource
to make it system-field-capable. It sets up serialization of a list
of configured "systemFields" in the JSON form of the input source, and
provides a method getSystemFieldValue for computing the value of each
system field. Cloud object, HDFS, HTTP, and Local now have this.
* Fix various LocalInputSource calls.
* Fix style stuff.
* Fixups.
* Fix tests and coverage.
ServiceClientImpl logs the cause of every retry, even though we are retrying the connection attempt. This leads to slight pollution in the logs because a lot of the time, the reason for retrying is the same. This is seen primarily in MSQ, when the worker task hasn't launched yet however controller attempts to connect to the worker task, which can lead to scary-looking messages (with INFO log level), even though they are normal.
This PR changes the logging logic to log every 10 (arbitrary number) retries instead of every retry, to reduce the pollution of the logs.
Note: If there are no retries left, the client returns an exception, which would get thrown up by the caller, and therefore this change doesn't hide any important information.
* Use min of scheduler threads and server threads for subquery guardrails.
This allows more memory to be used for subqueries when the query scheduler
is configured to limit queries below the number of server threads. The patch
also refactors the code so SubqueryGuardrailHelper is provided by a Guice
Provider rather than being created by ClientQuerySegmentWalker, to achieve
better separation of concerns.
* Exclude provider from coverage.
* Frames: consider writing singly-valued column when input column hasMultipleValues is UNKNOWN.
Prior to this patch, columnar frames would always write multi-valued columns if
the input column had hasMultipleValues = UNKNOWN. This had the effect of flipping
UNKNOWN to TRUE when copying data into frames, which is problematic because TRUE
causes expressions to assume that string inputs must be treated as arrays.
We now avoid this by flipping UNKNOWN to FALSE if no multi-valuedness
is encountered, and flipping it to TRUE if multi-valuedness is encountered.
* Add regression test case.
Currently the inter Druid communication via rest endpoints is based on json formatted payload. Upon parsing error, there is only a generic exception stating expected json token type and current json token type. There is no detailed error log about the content of the payload causing the violation.
In the micro-service world, the trend is to deploy the Druid servers in k8 with the mesh network. Often the istio proxy or other proxies is used to intercept the network connection between Druid servers. The proxy may give error messages for various reasons. These error messages are not expected by the json parser. The generic error message from Druid can be very misleading as the user may think the message is based on the response from the other Druid server.
For example, this is an example of mysterious error message
QueryInterruptedException{msg=Next token wasn't a START_ARRAY, was[VALUE_STRING] from url[http://xxxxx:8088/druid/v2/], code=Unknown exception, class=org.apache.druid.java.util.common.IAE, host=xxxxx:8088}"
While the context of the message is the following from the proxy when it can't tunnel the network connection.
pstream connect error or disconnect/reset before header
So this very simple PR is just to enhance the logging and get the real underlying message printed out. This would save a lot of head scratching time if Druid is deployed with mesh network.
Co-authored-by: Kai Sun <kai.sun@salesforce.com>
This PR aims to add the capabilities to:
1. Fetch the realtime segment metadata from the coordinator server view,
2. Adds the ability for workers to query indexers, similar to how brokers do the same for native queries.
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.
The aggregators had incorrect types for getResultType when shouldFinalze
is false. They had the finalized type, but they should have had the
intermediate type.
Also includes a refactor of how ExprMacroTable is handled in tests, to make
it easier to add tests for this to the MSQ module. The bug was originally
noticed because the incorrect result types caused MSQ queries with DS_HLL
to behave erratically.
Changes:
- Add task context parameter `taskLockType`. This determines the type of lock used by a batch task.
- Add new task actions for transactional replace and append of segments
- Add methods StorageCoordinator.commitAppendSegments and commitReplaceSegments
- Upgrade segments to appropriate versions when performing replace and append
- Add new metadata table `upgradeSegments` to track segments that need to be upgraded
- Add tests
- Add `KillTaskReport` that contains stats for `numSegmentsKilled`,
`numBatchesProcessed`, `numSegmentsMarkedAsUnused`
- Fix bug where exception message had no formatter but was was still being passed some args.
- Add some comments regarding deprecation of `markAsUnused` flag.
This commit pulls out some changes from #14407 to simplify that PR.
Changes:
- Rename `IndexerMetadataStorageCoordinator.announceHistoricalSegments` to `commitSegments`
- Rename the overloaded method to `commitSegmentsAndMetadata`
- Fix some typos
When materializing the results as frames, we defer the creation of the frames in ScanQueryQueryToolChest, which passes through the catch-all block reserved for catching cases when we don't have the complete row signature in the query (and falls back to the old code).
This PR aims to resolve it by adding the frame generation code to the try-catch block we have at the outer level.
Changes:
- Move following configs from `CliCoordinator` to `DruidCoordinatorConfig`:
- `druid.coordinator.kill.on`
- `druid.coordinator.kill.pendingSegments.on`
- `druid.coordinator.kill.supervisors.on`
- `druid.coordinator.kill.rules.on`
- `druid.coordinator.kill.audit.on`
- `druid.coordinator.kill.datasource.on`
- `druid.coordinator.kill.compaction.on`
- In the Coordinator style used by historical management duties, always instantiate all
the metadata cleanup duties but execute only if enabled. In the existing code, they are
instantiated only when enabled by using optional binding with Guice.
- Add a wrapper `MetadataManager` which contains handles to all the different
metadata managers for rules, supervisors, segments, etc.
- Add a `CoordinatorConfigManager` to simplify read and update of coordinator configs
- Remove persistence related methods from `CoordinatorCompactionConfig` and
`CoordinatorDynamicConfig` as these are config classes.
- Remove annotations `@CoordinatorIndexingServiceDuty`,
`@CoordinatorMetadataStoreManagementDuty`
changes:
* add back nested column v4 serializers
* 'json' schema by default still uses the newer 'nested common format' used by 'auto', but now has an optional 'formatVersion' property which can be specified to override format versions on native ingest jobs
* add system config to specify default column format stuff, 'druid.indexing.formats', and property 'druid.indexing.formats.nestedColumnFormatVersion' to specify system level preferred nested column format for friendly rolling upgrades from versions which do not support the newer 'nested common format' used by 'auto'
Changes:
- Add new metric `kill/pendingSegments/count` with dimension `dataSource`
- Add tests for `KillStalePendingSegments`
- Reduce no-op logs that spit out for each datasource even when no pending
segments have been deleted. This can get particularly noisy at low values of `indexingPeriod`.
- Refactor the code in `KillStalePendingSegments` for readability and add javadocs
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.
Currently, after an MSQ query, the web console is responsible for waiting for the segments to load. It does so by checking if there are any segments loading into the datasource ingested into, which can cause some issues, like in cases where the segments would never be loaded, or would end up waiting for other ingests as well.
This PR shifts this responsibility to the controller, which would have the list of segments created.
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:
- Make ServiceMetricEvent.Builder extend ServiceEventBuilder<ServiceMetricEvent>
and thus convert it to a plain builder rather than a builder of builder.
- Add methods setCreatedTime , setMetricAndValue to the builder
Changes:
- Reduce log level of some coordinator stats, which only denote normal coordinator operation.
These stats are still emitted and can be logged by setting debugDimensions in the coordinator
dynamic config.
- Initialize SegmentLoadingConfig only for historical management duties. This config is not
needed in other duties and initializing it creates logs which are misleading.
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.
There is a current issue due to inconsistent metadata between worker and controller in MSQ. A controller can receive one set of segments, which are then marked as unused by, say, a compaction job. The worker would be unable to get the segment information as MetadataResource.
Motivation:
- Clean up `DruidCoordinator` and move methods to classes where they are most relevant
Changes:
- No functional change
- Add duty `PrepareBalancerAndLoadQueues` to replace `UpdateCoordinatorState`
- Move map of `LoadQueuePeon` from `DruidCoordinator` to `LoadQueueTaskMaster`
- Make `BalancerStrategyFactory` an abstract class and keep the balancer executor here
- Move reporting of used segment stats and historical capacity stats from
`CollectSegmentAndServerStats` to `PrepareBalancerAndLoadQueues`
- Move reporting of unavailable and under-replicated segment stats from
`CollectSegmentAndServerStats` to `UpdateReplicationStatus` duty
Currently, Druid is using Guava 16.0.1 version. This upgrade to 31.1-jre fixes the following issues.
CVE-2018-10237 (Unbounded memory allocation in Google Guava 11.0 through 24.x before 24.1.1 allows remote attackers to conduct denial of service attacks against servers that depend on this library and deserialize attacker-provided data because the AtomicDoubleArray class (when serialized with Java serialization) and the CompoundOrdering class (when serialized with GWT serialization) perform eager allocation without appropriate checks on what a client has sent and whether the data size is reasonable). We don't use Java or GWT serializations. Despite being false positive they're causing red security scans on Druid distribution.
Latest version of google-client-api is incompatible with the existing Guava version. This PR unblocks Update google client apis to latest version #14414
Motivation:
- There is no usage of the `SegmentTransactionInsertAction` which passes a
non-null non-empty value of `segmentsToBeDropped`.
- This is not really needed either as overshadowed segments are marked as unused
by the Coordinator and need not be done in the same transaction as committing segments.
- It will also help simplify the changes being made in #14407
Changes:
- Remove `segmentsToBeDropped` from the task action and all intermediate methods
- Remove related tests which are not needed anymore
Changes:
- Move logic of `NewestSegmentFirstIterator.needsCompaction` to `CompactionStatus`
to improve testability and readability
- Capture the list of checks performed to determine if compaction is needed in a readable
manner in `CompactionStatus.CHECKS`
- Make `CompactionSegmentIterator` iterate over instances of `SegmentsToCompact`
instead of `List<DataSegment>`. This allows use of the `umbrellaInterval` later.
- Replace usages of `QueueEntry` with `SegmentsToCompact`
- Move `SegmentsToCompact` out of `NewestSegmentFirstIterator`
- Simplify `CompactionStatistics`
- Reduce level of less important logs to debug
- No change made to tests to ensure correctness
Changes:
- Use separate executor for every duty group
- This change is thread-safe as every duty group uses its own copy of
`DruidCoordinatorRuntimeParams` and does not share any other mutable instances
with other duty groups.
- With the exception of `HistoricalManagementDuties`, duty groups are typically not
very compute intensive and mostly perform database or HTTP I/O. So, coordinator
resources would still mostly be available for `HistoricalManagementDuties`.
Follow up changes to #12599
Changes:
- Rename column `used_flag_last_updated` to `used_status_last_updated`
- Remove new CLI tool `UpdateTables`.
- We already have a `CreateTables` with similar functionality, which should be able to
handle update cases too.
- Any user running the cluster for the first time should either just have `connector.createTables`
enabled or run `CreateTables` which should create tables at the latest version.
- For instance, the `UpdateTables` tool would be inadequate when a new metadata table has
been added to Druid, and users would have to run `CreateTables` anyway.
- Remove `upgrade-prep.md` and include that info in `metadata-init.md`.
- Fix log messages to adhere to Druid style
- Use lambdas
* 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
* Add supervisor /resetOffsets API.
- Add a new endpoint /druid/indexer/v1/supervisor/<supervisorId>/resetOffsets
which accepts DataSourceMetadata as a body parameter.
- Update logs, unit tests and docs.
* Add a new interface method for backwards compatibility.
* Rename
* Adjust tests and javadocs.
* Use CoreInjectorBuilder instead of deprecated makeInjectorWithModules
* UT fix
* Doc updates.
* remove extraneous debugging logs.
* Remove the boolean setting; only ResetHandle() and resetInternal()
* Relax constraints and add a new ResetOffsetsNotice; cleanup old logic.
* A separate ResetOffsetsNotice and some cleanup.
* Minor cleanup
* Add a check & test to verify that sequence numbers are only of type SeekableStreamEndSequenceNumbers
* Add unit tests for the no op implementations for test coverage
* CodeQL fix
* checkstyle from merge conflict
* Doc changes
* DOCUSAURUS code tabs fix. Thanks, Brian!
Changes:
- No change in behaviour if `smartSegmentLoading` is disabled
- If `smartSegmentLoading` is enabled
- Compute `balancerComputeThreads` based on `numUsedSegments`
- Compute `maxSegmentsToMove` based on `balancerComputeThreads`
- Compute `segmentsToMoveToFixSkew` based on usage skew
- Compute `segmentsToMove = Math.min(maxSegmentsToMove, segmentsToMoveToFixSkew)`
Limits:
- 1 <= `balancerComputeThreads` <= 8
- `maxSegmentsToMove` <= 20% of total segments
- `minSegmentsToMove` = 0.15% of total segments
`cachingCost` has been deprecated in #14484 and is not advised to be used in
production clusters as it may cause usage skew across historicals which the
coordinator is unable to rectify. This PR completely disables `cachingCost` strategy
as it has now been rendered redundant due to recent performance improvements
made to `cost` strategy.
Changes
- Disable `cachingCost` strategy
- Add `DisabledCachingCostBalancerStrategyFactory` for the time being so that we
can give a proper error message before falling back to `CostBalancerStrategy`. This
will be removed in subsequent releases.
- Retain `CachingCostBalancerStrategy` for testing/benchmarking purposes.
- Add javadocs to `DiskNormalizedCostBalancerStrategy`
### Description
Added the following metrics, which are calculated from the `KillUnusedSegments` coordinatorDuty
`"killTask/availableSlot/count"`: calculates the number remaining task slots available for auto kill
`"killTask/maxSlot/count"`: calculates the maximum number of tasks available for auto kill
`"killTask/task/count"`: calculates the number of tasks submitted by auto kill.
#### Release note
NEW: metrics added for auto kill
`"killTask/availableSlot/count"`: calculates the number remaining task slots available for auto kill
`"killTask/maxSlot/count"`: calculates the maximum number of tasks available for auto kill
`"killTask/task/count"`: calculates the number of tasks submitted by auto kill.
The current version of jackson-databind is flagged for vulnerabilities CVE-2020-28491 (Although cbor format is not used in druid), CVE-2020-36518 (Seems genuine as deeply nested json in can cause resource exhaustion). Updating the dependency to the latest version 2.12.7 to fix these vulnerabilities.
### 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)
### Description
Previously, the `maxSegments` configured for auto kill could be ignored if an interval of data for a given datasource had more than this number of unused segments, causing the kill task spawned with the task of deleting unused segments in that given interval of data to delete more than the `maxSegments` configured. Now each kill task spawned by the auto kill coordinator duty, will kill at most `limit` segments. This is done by adding a new config property to the `KillUnusedSegmentTask` which allows users to specify this limit.
* Minimize PostAggregator computations
Since a change back in 2014, the topN query has been computing
all PostAggregators on all intermediate responses from leaf nodes
to brokers. This generates significant slow downs for queries
with relatively expensive PostAggregators. This change rewrites
the query that is pushed down to only have the minimal set of
PostAggregators such that it is impossible for downstream
processing to do too much work. The final PostAggregators are
applied at the very end.
Changes:
- Add interface `SegmentDeleteHandler` for marking segments as unused
- In `StrategicSegmentAssigner`, collect all segments on which a drop rule applies in a list
- Process the list above as a batch delete rather than individual deletes
- Improve alert messages when an invalid tier is specified in a load rule
- Improve alert message when no rule applies on a segment
split KillUnusedSegmentsTask to smaller batches
Processing in smaller chunks allows the task execution to yield the TaskLockbox lock,
which allows the overlord to continue being responsive to other tasks and users while
this particular kill task is executing.
* introduce KillUnusedSegmentsTask batchSize parameter to control size of batching
* provide an explanation for kill task batchSize parameter
* add logging details for kill batch progress
Changes
- Rename `LoadQueuePeonTester` to `TestLoadQueuePeon`
- Simplify `TestLoadQueuePeon` by removing dependency on `CuratorLoadQueuePeon`
- Remove usages of mock peons in `LoadRuleTest` and use `TestLoadQueuePeon` instead
* allow for batched delete of segments instead of deleting segment data one by one
create new batchdelete method in datasegment killer that has default functionality
of iterating through all segments and calling delete on them. This will enable
a slow rollout of other deepstorage implementations to move to a batched delete
on their own time
* cleanup batchdelete segments
* batch delete with the omni data deleter
cleaned up code
just need to add tests and docs for this functionality
* update java doc to explain how it will try to use batch if function is overwritten
* rename killBatch to kill
add unit tests
* add omniDataSegmentKillerTest for deleting multiple segments at a time. fix checkstyle
* explain test peculiarity better
* clean up batch kill in s3.
* remove unused return value. cleanup comments and fix checkstyle
* default to batch delete. more specific java docs. list segments that couldn't be deleted
if there was a client error or server error
* simplify error handling
* add tests where an exception is thrown when killing multiple s3 segments
* add test for failing to delete two calls with the s3 client
* fix javadoc for kill(List<DataSegment> segments) clean up tests remove feature flag
* fix typo in javadocs
* fix test failure
* fix checkstyle and improve tests
* fix intellij inspections issues
* address comments, make delete multiple segments not assume same bucket
* fix test errors
* better grammar and punctuation. fix test. and better logging for exception
* remove unused code
* avoid extra arraylist instantiation
* fix broken test
* fix broken test
* fix tests to use assert.throws
* Merge core CoordinatorClient with MSQ CoordinatorServiceClient.
Continuing the work from #12696, this patch merges the MSQ
CoordinatorServiceClient into the core CoordinatorClient, yielding a single
interface that serves both needs and is based on the ServiceClient RPC
system rather than DruidLeaderClient.
Also removes the backwards-compatibility code for the handoff API in
CoordinatorBasedSegmentHandoffNotifier, because the new API was added
in 0.14.0. That's long enough ago that we don't need backwards
compatibility for rolling updates.
* Fixups.
* Trigger GHA.
* Remove unnecessary retrying in DruidInputSource. Add "about an hour"
retry policy and h
* EasyMock
* Use OverlordClient for all Overlord RPCs.
Continuing the work from #12696, this patch removes HttpIndexingServiceClient
and the IndexingService flavor of DruidLeaderClient completely. All remaining
usages are migrated to OverlordClient.
Supporting changes include:
1) Add a variety of methods to OverlordClient.
2) Update MetadataTaskStorage to skip the complete-task lookup when
the caller requests zero completed tasks. This helps performance of
the "get active tasks" APIs, which don't want to see complete ones.
* Use less forbidden APIs.
* Fixes from CI.
* Add test coverage.
* Two more tests.
* Fix test.
* Updates from CR.
* Remove unthrown exceptions.
* Refactor to improve testability and test coverage.
* Add isNil tests.
* Remove unnecessary "deserialize" methods.
Related to #14634
Changes:
- Update `IndexerSQLMetadataStorageCoordinator.deleteSegments` to use
JDBI PreparedBatch instead of issuing single DELETE statements
This PR uses the QoSFilter available in Jetty to park the query requests that exceed a configured limit. This is done so that other HTTP requests such as health check calls do not get blocked if the query server is busy serving long-running queries. The same mechanism can also be used in the future to isolate interactive queries from long-running select queries from interactive queries within the same broker.
Right now, you can still get that isolation by setting druid.query.scheduler.numThreads to a value lowe than druid.server.http.numThreads. That enables total laning but the side effect is that excess requests are not queued and rejected outright that leads to a bad user experience.
Parked requests are timed out after 30 seconds by default. I overrode that to the maxQueryTimeout in this PR.
changes:
* new filters that preserve match value typing to better handle filtering different column types
* sql planner uses new filters by default in sql compatible null handling mode
* remove isFilterable from column capabilities
* proper handling of array filtering, add array processor to column processors
* javadoc for sql test filter functions
* range filter support for arrays, tons more tests, fixes
* add dimension selector tests for mixed type roots
* support json equality
* rename semantic index maker thingys to mostly have plural names since they typically make many indexes, e.g. StringValueSetIndex -> StringValueSetIndexes
* add cooler equality index maker, ValueIndexes
* fix missing string utf8 index supplier
* expression array comparator stuff
Tests to verify the following behaviour have been added:
- Segments from more populous servers are more likely to be picked irrespective of
sample size.
- Segments from all servers are equally likely to be picked if all servers have equivalent
number of segments.
* Change default handoffConditionTimeout to 15 minutes.
Most of the time, when handoff is taking this long, it's because something
is preventing Historicals from loading new data. In this case, we have
two choices:
1) Stop making progress on ingestion, wait for Historicals to load stuff,
and keep the waiting-for-handoff segments available on realtime tasks.
(handoffConditionTimeout = 0, the current default)
2) Continue making progress on ingestion, by exiting the realtime tasks
that were waiting for handoff. Once the Historicals get their act
together, the segments will be loaded, as they are still there on
deep storage. They will just not be continuously available.
(handoffConditionTimeout > 0)
I believe most users would prefer [2], because [1] risks ingestion falling
behind the stream, which causes many other problems. It can cause data loss
if the stream ages-out data before we have a chance to ingest it.
Due to the way tuningConfigs are serialized -- defaults are baked into the
serialized form that is written to the database -- this default change will
not change anyone's existing supervisors. It will take effect for newly
created supervisors.
* Fix tests.
* Update docs/development/extensions-core/kafka-supervisor-reference.md
Co-authored-by: Katya Macedo <38017980+ektravel@users.noreply.github.com>
* Update docs/development/extensions-core/kinesis-ingestion.md
Co-authored-by: Katya Macedo <38017980+ektravel@users.noreply.github.com>
---------
Co-authored-by: Katya Macedo <38017980+ektravel@users.noreply.github.com>
* Add aggregatorMergeStrategy property to SegmentMetadaQuery.
- Adds a new property aggregatorMergeStrategy to segmentMetadata query.
aggregatorMergeStrategy currently supports three types of merge strategies -
the legacy strict and lenient strategies, and the new latest strategy.
- The latest strategy considers the latest aggregator from the latest segment
by time order when there's a conflict when merging aggregators from different
segments.
- Deprecate lenientAggregatorMerge property; The API validates that both the new
and old properties are not set, and returns an exception.
- When merging segments as part of segmentMetadata query, the segments have a more
elaborate id -- <datasource>_<interval>_merged_<partition_number> format, similar to
the name format that segments usually contain. Previously it was simply "merged".
- Adjust unit tests to test the latest strategy, to assert the returned complete
SegmentAnalysis object instead of just the aggregators for completeness.
* Don't explicitly set strict strategy in tests
* Apply suggestions from code review
Co-authored-by: Katya Macedo <38017980+ektravel@users.noreply.github.com>
* Update docs/querying/segmentmetadataquery.md
* Apply suggestions from code review
Co-authored-by: Katya Macedo <38017980+ektravel@users.noreply.github.com>
---------
Co-authored-by: Katya Macedo <38017980+ektravel@users.noreply.github.com>
* Add ZooKeeper connection state alerts and metrics.
- New metric "zk/connected" is an indicator showing 1 when connected,
0 when disconnected.
- New metric "zk/disconnected/time" measures time spent disconnected.
- New alert when Curator connection state enters LOST or SUSPENDED.
* Use right GuardedBy.
* Test fixes, coverage.
* Adjustment.
* Fix tests.
* Fix ITs.
* Improved injection.
* Adjust metric name, add tests.
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.
Description:
`TaskQueue.notifyStatus` is often a heavy call as it performs the following operations:
- Update task status in metadata DB
- Update task locks in metadata DB
- Request (synchronously) the task runner to shutdown the completed task
- Clean up in-memory data structures
This method can often be slow and can cause worker sync / task runners to slow down.
Main changes:
- Run task completion callbacks in a separate executor to handle task completion updates
- Add new config `druid.indexer.queue.taskCompleteHandlerNumThreads`
- Add metrics to monitor number of processed and queued items
- There are still other paths that can invoke `notifyStatus`, but those need not be moved to
the new executor as they are synchronous on purpose.
Other changes:
- Add new metrics `task/status/queue/count`, `task/status/handled/count`
- Add `TaskCountStatsProvider.getStats()` which deprecates the other `getXXXTaskCount` methods.
- Use `CoordinatorRunStats` to collect and report metrics. This class has been used as is
for now but will later be renamed and repurposed to use across all Druid services.
The wait doesn't seem to serve a purpose, other than causing delays
when checking isInitialized() for a large number of things that have
not yet been initialized.
UniformGranularityTest's test to test a large number of intervals
runs through 10 years of 1 second intervals. This pushes a lot of
stuff through IntervalIterator and shows up in terms of test
runtime as one of the hottest tests. Most of the time is going to
constructing jodatime objects because it is doing things with
DateTime objects instead of millis. Change the calls to use
millis instead and things go faster.
If a server is removed during `HttpServerInventoryView.serverInventoryInitialized`,
the initialization gets stuck as this server is never synced. The method eventually times
out (default 250s).
Fix: Mark a server as stopped if it is removed. `serverInventoryInitialized` only waits for
non-stopped servers to sync.
Other changes:
- Add new metrics for better debugging of slow broker/coordinator startup
- `segment/serverview/sync/healthy`: whether the server view is syncing properly with a server
- `segment/serverview/sync/unstableTime`: time for which sync with a server has been unstable
- Clean up logging in `HttpServerInventoryView` and `ChangeRequestHttpSyncer`
- Minor refactor for readability
- Add utility class `Stopwatch`
- Add tests and stubs
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
Bartosz Mikulski
Pramod Immaneni
Rishabh Singh
Zoltan Haindrich
AmatyaAvadhanula
zachjsh
Gian Merlino
Abhishek Agarwal
Abhishek Radhakrishnan
Karan Kumar
Sam Rash
Kashif Faraz
PANKAJ KUMAR
Pranav
Jonathan Wei
George Shiqi Wu
kaisun2000
Clint Wylie
Vishesh Garg
Jan Werner
Vadim Ogievetsky
Laksh Singla
Suneet Saldanha
Adarsh Sanjeev
Parth Agrawal
Zoltan Haindrich
Tejaswini Bandlamudi
Lucas Capistrant
imply-cheddar
Jason Koch
TSFenwick
aho135
hqx871