Today if we search across a large amount of shards we hit every shard. Yet, it's quite
common to search across an index pattern for time based indices but filtering will exclude
all results outside a certain time range ie. `now-3d`. While the search can potentially hit
hundreds of shards the majority of the shards might yield 0 results since there is not document
that is within this date range. Kibana for instance does this regularly but used `_field_stats`
to optimize the indexes they need to query. Now with the deprecation of `_field_stats` and it's upcoming removal a single dashboard in kibana can potentially turn into searches hitting hundreds or thousands of shards and that can easily cause search rejections even though the most of the requests are very likely super cheap and only need a query rewriting to early terminate with 0 results.
This change adds a pre-filter phase for searches that can, if the number of shards are higher than a the `pre_filter_shard_size` threshold (defaults to 128 shards), fan out to the shards
and check if the query can potentially match any documents at all. While false positives are possible, a negative response means that no matches are possible. These requests are not subject to rejection and can greatly reduce the number of shards a request needs to hit. The approach here is preferable to the kibana approach with field stats since it correctly handles aliases and uses the correct threadpools to execute these requests. Further it's completely transparent to the user and improves scalability of elasticsearch in general on large clusters.
We lost the cluster alias due to some special caseing in inner hits
and due to the fact that we didn't pass on the alias to the shard request.
This change ensures that we have the cluster alias present on the shard to
ensure all SearchShardTarget reads preserve the alias.
Relates to #25606
This commit changes how we determine if there were any remote indices that a search should have
been executed against. Previously, we used the list of remote shard iterators but if the remote
index pattern resolved to no indices there would be no remote shard iterators even though the
request specified remote indices. The map of remote cluster names to the original indices is used
instead so that we can determine if there were remote indices even when there are no remote shard
iterators.
Closes#25426
Today the `_field_caps` API doesn't implement its request serialization
correctly since indices and indices options are not serialized at all.
This will likely break with all transport clients etc. and if this request
must be send across the network. This commit fixes this and adds correct
handling if we have only remote indices to prevent the inclusion of
all local indices.
This commit renames all rest test files to use the .yml extension
instead of .yaml. This way the extension used within all of
elasticsearch for yaml is consistent.
This change simplifies how the rest test runner finds test files and
removes all leniency. Previously multiple prefixes and suffixes would
be tried, and tests could exist inside or outside of the classpath,
although outside of the classpath never quite worked. Now only classpath
tests are supported, and only one resource prefix is supported,
`/rest-api-spec/tests`.
closes#20240
After splitting integ tests into cluster configuration and the test
runner task, we still have dependencies of the test runner added as deps
of the cluster. This commit adds dependencies directly to the cluster,
so that the runner can have other dependencies independent of what is
needed for the cluster.
This is related to #23893. This commit allows users to use wilcards for
cluster names when executing a cross cluster search.
So instead of defining every cluster such as:
GET one:*,two:*,three:*/_search
A user could just search:
GET *:*/_search
As ":" characters are currently allowed in index names, if the text
up to the first ":" does not match a defined cluster name, the entire
string is treated as an index name.
All our actions that are invoked from rest actions have corresponding
transport actions. This adds the transport action for RestRemoteClusterInfoAction
for consistency.
Relates to #23969
Throw error when skip or do sections are malformed, such as they don't start with the proper token (START_OBJECT). That signals bad indentation, which would be ignored otherwise. Thanks (or due to) our pull parsing code, we were still able to properly parse the sections, yet other runners weren't able to.
Closes#21980
* [TEST] fix indentation in matrix_stats yaml tests
* [TEST] fix indentation in painless yaml test
* [TEST] fix indentation in analysis yaml tests
* [TEST] fix indentation in generated docs yaml tests
* [TEST] fix indentation in multi_cluster_search yaml tests
Gradle's finalizedBy on tasks only ensures one task runs after another,
but not immediately after. This is problematic for our integration tests
since it allows multiple project's integ test clusters to be
simultaneously. While this has not been a problem thus far (gradle 2.13
happened to keep the finalizedBy tasks close enough that no clusters
were running in parallel), with gradle 3.3 the task graph generation has
changed, and numerous clusters may be running simultaneously, causing
memory pressure, and thus generally slower tests, or even failure if the
system has a limited amount of memory (eg in a vagrant host).
This commit reworks how integ tests are configured. It adds an
`integTestCluster` extension to gradle which is equivalent to the current
`integTest.cluster` and moves the rest test runner task to
`integTestRunner`. The `integTest` task is then just a dummy task,
which depends on the cluster runner task, as well as the cluster stop
task. This means running `integTest` in one project will both run the
rest tests, and shut down the cluster, before running `integTest` in
another project.
Today either all nodes in the cluster connect to remote clusters of only nodes
that have remote clusters configured in their node config. To allow global remote
cluster configuration but restrict connections to a set of nodes in the cluster
this change adds a new setting `search.remote.connect` (defaults to `true`) to allow
to disable remote cluster connections on a per node basis.
Instead of `search.remote.seeds.${clustername}` we now specify the seeds as:
`search.remote.${clustername}.seeds` which is a real list setting compared to an unvalidated
group setting before.
this commit adds full support for proxy nodes on the search layer.
This allows to connection only to a small set of nodes on a remote cluster
to exectue the search. The nodes will proxy the request to the correct node in the
cluster while the coordinting node doesn't need to be connected to the target node.
This commit adds `qa/multi-cluster-search` which currently does a
simple search across 2 clusters. This commit also adds support for IPv6
addresses and fixes an issue where all shards of the local cluster are searched
when only a remote index was given.
Simon Willnauer
Jay Modi
Ryan Ernst
Tim Brooks
Luca Cavanna
javanna