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.
The created and found fields in index and delete responses became obsolete after the introduction of the result field in index, update and delete responses (#19566).
After deprecating the created and found fields in 5.x (#19633), now they are removed.
Fixes#19630
* Add MSI installation to documentation
Move installation documentation for Windows with the .zip archive into the zip and tar installation documentation, and clearly indicate any differences for installing on macOS/Linux and Windows.
* Separate out installation with .zip on Windows
This commit adds a document describing our data replication model in high level terms. The goal is give people basic insight into how things work in order to better understand how read and writes interact, both during normal operations and under failures.
* Scripting: Remove groovy scripting language
Groovy was deprecated in 5.0. This change removes it, along with the
legacy default language infrastructure in scripting.
* master: (22 commits)
Add proper toString() method to UpdateTask (#21582)
Fix `InternalEngine#isThrottled` to not always return `false`. (#21592)
add `ignore_missing` option to SplitProcessor (#20982)
fix trace_match behavior for when there is only one grok pattern (#21413)
Remove dead code from GetResponse.java
Fixes date range query using epoch with timezone (#21542)
Do not cache term queries. (#21566)
Updated dynamic mapper section
Docs: Clarify date_histogram bucket sizes for DST time zones
Handle release of 5.0.1
Fix skip reason for stats API parameters test
Reduce skip version for stats API parameter tests
Strict level parsing for indices stats
Remove cluster update task when task times out (#21578)
[DOCS] Mention "all-fields" mode doesn't search across nested documents
InternalTestCluster: when restarting a node we should validate the cluster is formed via the node we just restarted
Fixed bad asciidoc in boolean mapping docs
Fixed bad asciidoc ID in node stats
Be strict when parsing values searching for booleans (#21555)
Fix time zone rounding edge case for DST overlaps
...
* master:
ShardActiveResponseHandler shouldn't hold to an entire cluster state
Ensures cleanup of temporary index-* generational blobs during snapshotting (#21469)
Remove (again) test uses of onModule (#21414)
[TEST] Add assertBusy when checking for pending operation counter after tests
Revert "Add trace logging when aquiring and releasing operation locks for replication requests"
Allows multiple patterns to be specified for index templates (#21009)
[TEST] fixes rebalance single shard check as it isn't guaranteed that a rebalance makes sense and the method only tests if rebalance is allowed
Document _reindex with random_score
With the unified release process across the elastic stack, download
links for all products are changing. This change updates docs referring
to the old download and packages urls.
Note that this change also updates the plugin installation command as
the url for downloads is being changed to be consistent with that for
packages (both plural).
Funny node names have been removed in #19456 and replaced by UUID. This commit removes these obsolete node names and replace them by real UUIDs in the documentation.
closes#20065
`gender.keyword` should be used instead of just `gender` or we
get an error `Fielddata is disabled on text fields by default. Set
fielddata=true on [gender] in order to load fielddata in memory by
uninverting the inverted index. Note that this can however use
Closes#20535
significant memory.`
Today when parsing settings during bootstrap, we add a system property
for every Elasticsearch setting. Additionally, settings can be set via
system properties. This commit simplifies this situation.
- settings are no longer propogated to system properties
- system properties can not be used to set settings
- the "es." prefix on settings is no longer required (nor permitted)
- test logging has a dedicated system property (tests.logger.level)
Relates #18198
The getting started docs use dynamic mappings. With the recent change to
string split into text and keyword, text lost the default ability to do
aggs. This was added back in #17188. This change updates the getting
started examples to use the keyword multi field added to dynamically
mapped text fields.
closes#17941
Today, certain bootstrap properties are set and read via system
properties. This action-at-distance way of managing these properties is
rather confusing, and completely unnecessary. But another problem exists
with setting these as system properties. Namely, these system properties
are interpreted as Elasticsearch settings, not all of which are
registered. This leads to Elasticsearch failing to startup if any of
these special properties are set. Instead, these properties should be
kept as local as possible, and passed around as method parameters where
needed. This eliminates the action-at-distance way of handling these
properties, and eliminates the need to register these non-setting
properties. This commit does exactly that.
Additionally, today we use the "-D" command line flag to set the
properties, but this is confusing because "-D" is a special flag to the
JVM for setting system properties. This creates confusion because some
"-D" properties should be passed via arguments to the JVM (so via
ES_JAVA_OPTS), and some should be passed as arguments to
Elasticsearch. This commit changes the "-D" flag for Elasticsearch
settings to "-E".