This makes a `parentCardinality` available to every `Aggregator`'s ctor
so it can make intelligent choices about how it collects bucket values.
This replaces `collectsFromSingleBucket` and is similar to it but:
1. It supports `NONE`, `ONE`, and `MANY` values and is generally
extensible if we decide we can use more precise counts.
2. It is more accurate. `collectsFromSingleBucket` assumed that all
sub-aggregations live under multi-bucket aggregations. This is
normally true but `parentCardinality` is properly carried forward
for single bucket aggregations like `filter` and for multi-bucket
aggregations configured in single-bucket for like `range` with a
single range.
While I was touching every aggregation I renamed `doCreateInternal` to
`createMapped` because that seemed like a much better name and it was
right there, next to the change I was already making.
Relates to #56487
Co-authored-by: Elastic Machine <elasticmachine@users.noreply.github.com>
Working through a heap dump for an unrelated issue I found that we can easily rack up
tens of MBs of duplicate empty instances in some cases.
I moved to a static constructor to guard against that in all cases.
- The exception that we caught when failing to schedule a thread was incorrect.
- We may have failures when reducing the response before returning it, which were not handled correctly and may have caused get or submit async search task to not be properly unregistered from the task manager
- when the completion listener onFailure method is invoked, the search task has to be unregistered. Not doing so may cause the search task to be stuck in the task manager although it has completed.
Closes#58995
This change allows the submit async search task to cancel children
and removes the manual indirection that cancels the search task when the submit
task is cancelled. This is now handled by the task cancellation, which can cancel
grand-children since #54757.
This commit fixes an AOOBE in the handling of fatal
failures in _async_search. If the underlying cause is not found,
this change uses the root failure.
Closes#58311
This makes it easier to debug where such tasks come from in case they are returned from the get tasks API.
Also renamed the last occurrence of waitForCompletion to waitForCompletionTimeout in get async search request.
This change ensures that we stop the maintenance service on all nodes
when a data node is restarted. This ensures that we don't send
update_by_query requests on the node that is restarted.
This commit also raises the log level to trace for some packages
in order to investigate the failures to acquire a shard lock
after a restart.
Relates #56765
This change ensures that the maintenance service that is responsible for deleting the expired response is stopped between each test. This is needed since we check that no search context are in-flight after each test method.
Fixes#55988
Async search integration tests are subject to random failures when:
* The test index has more than one replica.
* The request cache is used.
* Some shards are empty.
* The maintenance service starts a garbage collection when node is closing.
They are also slow because the test index is created/populated on each
test method.
This change refactors these integration tests in order to:
* Create the index once for the entire test suite.
* Fix the usage of the request cache and replicas.
* Ensures that all shards have at least one document.
* Increase the delay of the maintenance service garbage collection.
Closes#55895Closes#55988
Async search allows users to retrieve partial results for a running search. For partial results, the number of successful shards does not include the skipped shards, while the response returned to users should.
Also, we recently had a bug where async search would miss tracking shard failures, which would have been caught if we had assertions in place that verified that whenever we get the last response, the number of failures included in it is the same as the failures that were tracked through the listener notifications.
This commit includes a number of minor improvements around `DelayableWriteable`: javadocs were expanded and reworded, `get` was renamed to `expand` and `DelayableWriteable` no longer implements `Supplier`. Also a couple of methods are now private instead of package private.
This replaces a reference to the result of partially reducing
aggregations that async search keeps with a reference to the serialized
form of the result of the partial reduction which we need to keep
anyway.
This change turns the AsyncSearchMaintenanceService into an
AbstractLifecycleComponent and ensures that the service is
stopped when a node is closing.
Closes#55646
The (de)serialization code of the async search response
cannot handle exceptions that extend ElasticsearchException (e.g. ScriptException).
This commit fixes this bug by serializing the error with the more generic
StreamInput#writeException.
EQL will require very similar functionality to async search. This PR refactors
AsyncSearchIndexService to make it reusable for EQL.
Supersedes #55119
Relates to #49638
This change ensures that we return the latest expiration time
when retrieving the response from the index.
This commit also fixes a bug that stops the garbage collection of saved responses if the async search index is deleted.
Today we pass the `RepositoriesService` to the searchable snapshots plugin
during the initialization of the `RepositoryModule`, forcing the plugin to be a
`RepositoryPlugin` even though it does not implement any repositories.
After discussion we decided it best for now to pass this in via
`Plugin#createComponents` instead, pending some future work in which plugins
can depend on services more dynamically.
We currently create the .async-search index if necessary before performing any action (index, update or delete). Truth is that this is needed only before storing the initial response. The other operations are either update or delete, which will anyways not find the document to update/delete even if the index gets created when missing. This also caused `testCancellation` failures as we were trying to delete the document twice from the .async-search index, once from `TransportDeleteAsyncSearchAction` and once as a consequence of the search task being completed. The latter may be called after the test is completed, but before the cluster is shut down and causing problems to the after test checks, for instance if it happens after all the indices have been cleaned up. It is totally fine to try to delete a response that is no longer found, but not quite so if such call will also trigger an index creation.
With this commit we remove all the calls to createIndexIfNecessary from the update/delete operation, and we leave one call only from storeInitialResponse which is where the index is expected to be created.
Closes#54180
This removes pipeline aggregators from the aggregation result tree
except for a single field used for backwards compatibility with pre-7.8
versions of Elasticsearch. That field isn't populated unless we are
serializing to pre-7.8 Elasticsearch. So, good news! We no longer build
pipeline aggregators on the data node. Most of the time.
This change adds the response headers of the original search request
in the stored response in order to be able to restore them when retrieving a result
from the async-search index. It also ensures that response headers are preserved for
users that retrieve a final response on a running search task.
Partial response can eventually return response headers too but this change only ensures
that they are present when the response if final.
Relates #33936
`AsyncSearchActionTests` currently fails quite often. That is since the introduction of `RestSubmitAsyncSearchActionTests` which indirectly manipulates the channels being tracked in `RestCancellableNodeClient`. There are channels left in the map after `RestSubmitAsyncSearchActionTests` is run, and later `AsyncSearchActionTests` checks that there are no channels in the map which makes each test method fail. This is particularily hard to reproduce as the order in which tests are run appears to be platform dependent.
The test cluster assertion that there are no channels in the map only makes sense in the context of internal cluster tests, while there may be collisions with unit tests that register http channels as part of their testing.
This can be solved by renaming `AsyncSearchActionTests` to `AsyncSearchActionIT`. This way it won't be run as part of unit tests but rather within another JVM where the number of channels is `0` and such assumption holds, because there are no expected manual manipulation of the channels.
Relates to #54180
This is a simple naming change PR, to fix the fact that "metadata" is a
single English word, and for too long we have not followed general
naming conventions for it. We are also not consistent about it, for
example, METADATA instead of META_DATA if we were trying to be
consistent with MetaData (although METADATA is correct when considered
in the context of "metadata"). This was a simple find and replace across
the code base, only taking a few minutes to fix this naming issue
forever.
Pipeline aggregations like `stats_bucket`, `sum_bucket`, and
`percentiles_bucket` only operate on buckets that have multiple buckets.
This adds support for those aggregations to `geo_distance`, `ip_range`,
`auto_date_histogram`, and `rare_terms`.
This all happened because we used a marker interface to mark compatible
aggs, `MultiBucketAggregationBuilder` and it was fairly easy to forget
to implement the interface.
This replaces the marker interface with an abstract method in
`AggregationBuilder`, `bucketCardinality` which makes you return `NONE`,
`ONE`, or `MANY`. The `bucket` aggregations can check for `MANY`. At
this point `ONE` and `NONE` amount to about the same thing, but I
suspect that'll be a useful distinction when validating bucket sorts.
Closes#53215
Currently we set the defaults for ccsMinimizeRoundtrips, preFilterShardSize and
requestCache on the HLRC SubmitAsyncSearchRequest in the constructor. This is no
longer needed since we now only send the parameters along with the rest request
that are supported (omitting e.g. ccsMinimizeRoundtrips) and the correct
defaults are set on the client side. This change removes setting and sending
these defaults where possible, leaving only the overwrite of batchedReduceSize
with a default value of 5, since the default used in the vanilla SearchRequest
is 512. However, we don't need to send this value along as a request parameter
if its the default since the correct one will be set on the receiving end if no
value is specified.
Also adding tests for RestSubmitAsyncSearchAction that check the correct
defaults are set when parameters are missing on the server side.
Backport of #54200
Changes ThreadPool's schedule method to run the schedule task in the context of the thread
that scheduled the task.
This is the more sensible default for this method, and eliminates a range of bugs where the
current thread context is mistakenly dropped.
Closes#17143
This commit renames wait_for_completion to wait_for_completion_timeout in submit async search and get async search.
Also it renames clean_on_completion to keep_on_completion and turns around its behaviour.
Closes#54069
Submit async search forces pre_filter_shard_size for the underlying search that it creates.
With this commit we also prevent users from overriding such default as part of request validation.
This commit adds an explicit cancellation of the search task if
the initial async search submit task is cancelled (connection closed by the user).
This was previously done through the cancellation of the parent task but we don't
handle grand-children cancellation yet so we have to manually cancel the search task
in order to ensure that shard actions are cancelled too.
This change can be considered as a workaround until #50990 is fixed.
* Get Async Search: omit _clusters section when empty (#53907)
The _clusters section is omitted by the search API whenever no remote clusters are searched. Async search should do the same, but Get Async Search returns a deserialized response, hence a weird `_clusters` section with all values set to `0` gets returned instead. In fact the recreated Clusters object is not the same object as the EMPTY constant, yet it has the same content.
This commit addresses this by changing the comparison in the `toXContent` method to not print out the section if the number of total clusters is `0`.
* Async search: remove version from response (#53960)
The goal of the version field was to quickly show when you can expect to find something new in the search response, compared to when nothing has changed. This can also be done by looking at the `_shards` section and `num_reduce_phases` returned with the search response. In fact when there has been one or more additional reduction of the results, you can expect new results in the search response. Otherwise, the `_shards` section could notify of additional failures of shards that have completed the query, but that is not a guarantee that their results will be exposed (only when the following partial reduction is performed their results will be available).
That said this commit clarifies this in the docs and removes the version field from the async search response
* Async Search: replicas to auto expand from 0 to 1 (#53964)
This way single node clusters that are green don't go yellow once async search is used, while
all the others still have one replica.
* [DOCS] address timing issue in async search docs tests (#53910)
The docs snippets for submit async search have proven difficult to test as it is not possible to guarantee that you get a response that is not final, even when providing `wait_for_completion=0`. In the docs we want to show though a proper long-running query, and its first response should be partial rather than final.
With this commit we adapt the docs snippets to show a partial response, and replace under the hood all that's needed to make the snippets tests succeed when we get a final response. Also, increased the timeout so we always get a final response.
Closes#53887Closes#53891
* Submit async search to work only with POST (#53368)
Currently the submit async search API can be called using both GET and POST at REST, but given that it submits a call and creates internal state, POST should be the only allowed method.
* Refine SearchProgressListener internal API (#53373)
The following cumulative improvements have been made:
- rename `onReduce` and `notifyReduce` to `onFinalReduce` and `notifyFinalReduce`
- add unit test for `SearchShard`
- on* methods in `SearchProgressListener` shouldn't need to be public as they should never be called directly, they only need to be overridden hence they can be made protected. They are actually called directly from a test which required some adapting, like making `AsyncSearchTask.Listener` class package private instead of private
- Instead of overriding `getProgressListener` in `AsyncSearchTask`, as it feels weird to override a getter method, added a specific method that allows to retrieve the Listener directly without needing to cast it. Made the getter and setter for the listener final in the base class.
- rename `SearchProgressListener#searchShards` methods to `buildSearchShards` and make it static given that it accesses no instance members
- make `SearchShard` and `SearchShardTask` classes final
* Move async search yaml tests to x-pack yaml test folder (#53537)
The yaml tests for async search currently sit in its qa folder. There is no reason though for them to live in a separate folder as they don't require particular setup. This commit moves them to the main folder together with the other x-pack yaml tests so that they will be run by the client test runners too.
* [DOCS] Add temporary redirect for async-search (#53454)
The following API spec files contain a link to a not-yet-created
async search docs page:
* [async_search.delete.json][0]
* [async_search.get.json][1]
* [async_search.submit.json][2]
The Elaticsearch-js client uses these spec files to create their docs.
This created a broken link in the Elaticsearch-js docs, which has broken
the docs build.
This PR adds a temporary redirect for the docs page. This redirect
should be removed when the actual API docs are added.
[0]: https://github.com/elastic/elasticsearch/blob/master/x-pack/plugin/src/test/resources/rest-api-spec/api/async_search.delete.json
[1]: https://github.com/elastic/elasticsearch/blob/master/x-pack/plugin/src/test/resources/rest-api-spec/api/async_search.get.json
[2]: https://github.com/elastic/elasticsearch/blob/master/x-pack/plugin/src/test/resources/rest-api-spec/api/async_search.submit.json
Co-authored-by: James Rodewig <james.rodewig@elastic.co>
This begins to clean up how `PipelineAggregator`s and executed.
Previously, we would create the `PipelineAggregator`s on the data nodes
and embed them in the aggregation tree. When it came time to execute the
pipeline aggregation we'd use the `PipelineAggregator`s that were on the
first shard's results. This is inefficient because:
1. The data node needs to make the `PipelineAggregator` only to
serialize it and then throw it away.
2. The coordinating node needs to deserialize all of the
`PipelineAggregator`s even though it only needs one of them.
3. You end up with many `PipelineAggregator` instances when you only
really *need* one per pipeline.
4. `PipelineAggregator` needs to implement serialization.
This begins to undo these by building the `PipelineAggregator`s directly
on the coordinating node and using those instead of the
`PipelineAggregator`s in the aggregtion tree. In a follow up change
we'll stop serializing the `PipelineAggregator`s to node versions that
support this behavior. And, one day, we'll be able to remove
`PipelineAggregator` from the aggregation result tree entirely.
Importantly, this doesn't change how pipeline aggregations are declared
or parsed or requested. They are still part of the `AggregationBuilder`
tree because *that* makes sense.
This change removes the need to always get a new version when iterating
on an async search. This is needed since we cannot guarantee that shards will
be queried exactly in order.
Relates #53360
This change introduces a new API in x-pack basic that allows to track the progress of a search.
Users can submit an asynchronous search through a new endpoint called `_async_search` that
works exactly the same as the `_search` endpoint but instead of blocking and returning the final response when available, it returns a response after a provided `wait_for_completion` time.
````
GET my_index_pattern*/_async_search?wait_for_completion=100ms
{
"aggs": {
"date_histogram": {
"field": "@timestamp",
"fixed_interval": "1h"
}
}
}
````
If after 100ms the final response is not available, a `partial_response` is included in the body:
````
{
"id": "9N3J1m4BgyzUDzqgC15b",
"version": 1,
"is_running": true,
"is_partial": true,
"response": {
"_shards": {
"total": 100,
"successful": 5,
"failed": 0
},
"total_hits": {
"value": 1653433,
"relation": "eq"
},
"aggs": {
...
}
}
}
````
The partial response contains the total number of requested shards, the number of shards that successfully returned and the number of shards that failed.
It also contains the total hits as well as partial aggregations computed from the successful shards.
To continue to monitor the progress of the search users can call the get `_async_search` API like the following:
````
GET _async_search/9N3J1m4BgyzUDzqgC15b/?wait_for_completion=100ms
````
That returns a new response that can contain the same partial response than the previous call if the search didn't progress, in such case the returned `version`
should be the same. If new partial results are available, the version is incremented and the `partial_response` contains the updated progress.
Finally if the response is fully available while or after waiting for completion, the `partial_response` is replaced by a `response` section that contains the usual _search response:
````
{
"id": "9N3J1m4BgyzUDzqgC15b",
"version": 10,
"is_running": false,
"response": {
"is_partial": false,
...
}
}
````
Asynchronous search are stored in a restricted index called `.async-search` if they survive (still running) after the initial submit. Each request has a keep alive that defaults to 5 days but this value can be changed/updated any time:
`````
GET my_index_pattern*/_async_search?wait_for_completion=100ms&keep_alive=10d
`````
The default can be changed when submitting the search, the example above raises the default value for the search to `10d`.
`````
GET _async_search/9N3J1m4BgyzUDzqgC15b/?wait_for_completion=100ms&keep_alive=10d
`````
The time to live for a specific search can be extended when getting the progress/result. In the example above we extend the keep alive to 10 more days.
A background service that runs only on the node that holds the first primary shard of the `async-search` index is responsible for deleting the expired results. It runs every hour but the expiration is also checked by running queries (if they take longer than the keep_alive) and when getting a result.
Like a normal `_search`, if the http channel that is used to submit a request is closed before getting a response, the search is automatically cancelled. Note that this behavior is only for the submit API, subsequent GET requests will not cancel if they are closed.
Asynchronous search are not persistent, if the coordinator node crashes or is restarted during the search, the asynchronous search will stop. To know if the search is still running or not the response contains a field called `is_running` that indicates if the task is up or not. It is the responsibility of the user to resume an asynchronous search that didn't reach a final response by re-submitting the query. However final responses and failures are persisted in a system index that allows
to retrieve a response even if the task finishes.
````
DELETE _async_search/9N3J1m4BgyzUDzqgC15b
````
The response is also not stored if the initial submit action returns a final response. This allows to not add any overhead to queries that completes within the initial `wait_for_completion`.
The `.async-search` index is a restricted index (should be migrated to a system index in +8.0) that is accessible only through the async search APIs. These APIs also ensure that only the user that submitted the initial query can retrieve or delete the running search. Note that admins/superusers would still be able to cancel the search task through the task manager like any other tasks.
Relates #49091
Co-authored-by: Luca Cavanna <javanna@users.noreply.github.com>
Nik Everett
Armin Braun
Luca Cavanna
Igor Motov
Jim Ferenczi
David Kyle
Ryan Ernst
Mark Vieira
David Roberts
David Turner
Jason Tedor
Christoph Büscher
Yannick Welsch