[[release-notes-7.9.3]]
== {es} version 7.9.3

Also see <<breaking-changes-7.9,Breaking changes in 7.9>>.

[[bug-7.9.3]]
[float]
=== Bug fixes

Allocation::
* InternalClusterInfoService should not ignore hidden indices {es-pull}62995[#62995]

Audit::
* Move RestRequestFilter to core {es-pull}63507[#63507]

Authentication::
* Ensure domain_name setting for AD realm is present {es-pull}61983[#61983] (issue: {es-issue}61859[#61859])

Authorization::
* Fix API key role descriptors rewrite bug for upgraded clusters {es-pull}62917[#62917] (issue: {es-issue}62911[#62911])

CCR::
* Retry CCR shard follow task when no seed node left {es-pull}63225[#63225]

Cluster Coordination::
* Uniquely associate term with update task during election {es-pull}62212[#62212] (issue: {es-issue}61437[#61437])

EQL::
* Avoid filtering on tiebreakers {es-pull}63215[#63215] (issue: {es-issue}62781[#62781])
* Fix bug in sequences with any pattern {es-pull}63007[#63007] (issue: {es-issue}62967[#62967])

Engine::
* Fix to actually throttle indexing on getting activated {es-pull}61768[#61768]

Features/Data streams::
* Fix querying a data stream name in index field {es-pull}63170[#63170]

Features/Ingest::
* Handle error conditions when simulating ingest pipelines with verbosity enabled {es-pull}63327[#63327] (issue: {es-issue}63199[#63199])
* Make for each processor resistant to field modification {es-pull}62791[#62791] (issue: {es-issue}62790[#62790])

Machine Learning::
* Fix online updates with custom rules referencing filters {es-pull}63057[#63057] (issue: {es-issue}62948[#62948])
* Reset reindexing progress when data frame analytics job resumes with incomplete reindexing {es-pull}62772[#62772]

SQL::
* Fix exception when using CAST on inexact field {es-pull}62943[#62943] (issue: {es-issue}60178[#60178])

Search::
* Async search should retry updates on version conflict {es-pull}63652[#63652] (issue: {es-issue}63213[#63213])

Transform::
* Fix possible NPE if transform task has no node assigned {es-pull}62946[#62946] (issue: {es-issue}62847[#62847])
* Filter null objects from field caps request {es-pull}62945[#62945]



[[upgrade-7.9.3]]
[float]
=== Upgrades

Infra/Packaging::
* Switch bundled JDK back to Oracle JDK {es-pull}63288[#63288] (issue: {es-issue}62709[#62709])


[[release-notes-7.9.2]]
== {es} version 7.9.2

Also see <<breaking-changes-7.9,Breaking changes in 7.9>>.

[[deprecation-7.9.2]]
[float]
=== Deprecations

Infra/Plugins::
* Deprecate xpack.eql.enabled setting and make it a no-op {es-pull}61375[#61375] (issue: {es-issue}54745[#54745])

[[enhancement-7.9.2]]
[float]
=== Enhancements

Mapping::
* Improve error messages on bad [format] and [null_value] params for date mapper {es-pull}61932[#61932] (issue: {es-issue}61712[#61712])

[[bug-7.9.2]]
[float]
=== Bug fixes

Aggregations::
* Cardinality request breaker leak {es-pull}62685[#62685] (issue: {es-issue}62439[#62439])
* Fix bug with terms' min_doc_count {es-pull}62130[#62130] (issue: {es-issue}62084[#62084])

Analysis::
* Fix standard filter BWC check to allow for cacheing bug {es-pull}62649[#62649] (issues: {es-issue}33310[#33310], {es-issue}51092[#51092], {es-issue}62644[#62644])

Authentication::
* Ensure domain_name setting for AD realm is present {es-pull}61859[#61859]
* Update authc failure headers on license change {es-pull}61734[#61734] (issue: {es-issue}56318[#56318])

Authorization::
* Ensure authz operation overrides transient authz headers {es-pull}61621[#61621]

CCR::
* CCR should retry on CircuitBreakingException {es-pull}62013[#62013] (issue: {es-issue}55633[#55633])

EQL::
* Create the search request with a list of indices {es-pull}62005[#62005] (issue: {es-issue}60793[#60793])

Engine::
* Allow enabling soft-deletes on restore from snapshot {es-pull}62018[#62018] (issue: {es-issue}61969[#61969])

Features/Data streams::
* Always validate that only a create op is allowed in bulk api for data streams {es-pull}62766[#62766] (issue: {es-issue}62762[#62762])
* Fix NPE when deleting multiple backing indices on a data stream {es-pull}62274[#62274] (issue: {es-issue}62272[#62272])
* Fix data stream wildcard resolution bug in eql search api. {es-pull}61904[#61904] (issue: {es-issue}60828[#60828])
* Prohibit the usage of create index api in namespaces managed by data stream templates {es-pull}62527[#62527]

Features/ILM+SLM::
* Fix condition in ILM step that cannot be met {es-pull}62377[#62377]

Features/Ingest::
* Add Missing NamedWritable Registration for ExecuteEnrichPolicyStatus {es-pull}62364[#62364]

Features/Java High Level REST Client::
* Drop assertion that rest client response warnings conform to RFC 7234 {es-pull}61365[#61365] (issues: {es-issue}60889[#60889], {es-issue}61259[#61259])

Infra/Packaging::
* Check glibc version {es-pull}62728[#62728] (issue: {es-issue}62709[#62709])

Machine Learning::
* Add null checks for C++ log handler {es-pull}62238[#62238]
* Persist progress when setting data frame analytics task to failed {es-pull}61782[#61782]
* Fix reporting of peak memory usage in memory stats for data frame analytics {ml-pull}1468[#1468]
* Fix reporting of peak memory usage in model size stats for anomaly detection {ml-pull}1484[#1484]

Mapping::
* Allow empty null values for date and IP field mappers {es-pull}62487[#62487] (issues: {es-issue}57666[#57666], {es-issue}62363[#62363])
* Take resolution into account when parsing date null value {es-pull}61994[#61994]

Network::
* Log alloc description after netty processors set {es-pull}62741[#62741]

SQL::
* Do not resolve self-referencing aliases {es-pull}62382[#62382] (issue: {es-issue}62296[#62296])

Search::
* Fix disabling `allow_leading_wildcard` {es-pull}62300[#62300] (issues: {es-issue}60959[#60959], {es-issue}62267[#62267])
* Search memory leak {es-pull}61788[#61788]

Transform::
* Disable optimizations when using scripts in group_by {es-pull}60724[#60724] (issue: {es-issue}57332[#57332])



[[upgrade-7.9.2]]
[float]
=== Upgrades

Infra/Packaging::
* Upgrade the bundled JDK to JDK 15 {es-pull}62580[#62580]

[[release-notes-7.9.1]]
== {es} version 7.9.1

Also see <<breaking-changes-7.9,Breaking changes in 7.9>>.

[[feature-7.9.1]]
[float]
=== New features

Search::
* QL: Wildcard field type support {es-pull}58062[#58062] (issues: {es-issue}54184[#54184], {es-issue}58044[#58044])



[[enhancement-7.9.1]]
[float]
=== Enhancements

CRUD::
* Log more information when mappings fail on index creation {es-pull}61577[#61577]

EQL::
* Make endsWith function use a wildcard ES query wherever possible {es-pull}61160[#61160] (issue: {es-issue}61154[#61154])
* Make stringContains function use a wildcard ES query wherever possible {es-pull}61189[#61189] (issue: {es-issue}58922[#58922])

Features/Stats::
* Change severity of negative stats messages from WARN to DEBUG {es-pull}60375[#60375]

Search::
* Fix handling of alias filter in SearchService#canMatch {es-pull}59368[#59368] (issue: {es-issue}59367[#59367])
* QL: Add filtering Query DSL support to IndexResolver {es-pull}60514[#60514] (issue: {es-issue}57358[#57358])

Snapshot/Restore::
* Do not access snapshot repo on dedicated voting-only master node {es-pull}61016[#61016] (issue: {es-issue}59649[#59649])



[[bug-7.9.1]]
[float]
=== Bug fixes

Authentication::
* Call ActionListener.onResponse exactly once {es-pull}61584[#61584]

Authorization::
* Relax the index access control check for scroll searches {es-pull}61446[#61446]

CCR::
* Relax ShardFollowTasksExecutor validation {es-pull}60054[#60054] (issue: {es-issue}59625[#59625])
* Set timeout of auto put-follow request to unbounded {es-pull}61679[#61679] (issue: {es-issue}56891[#56891])
* Set timeout of master node requests on follower to unbounded {es-pull}60070[#60070] (issue: {es-issue}56891[#56891])

Cluster Coordination::
* Restrict testing of legacy discovery to tests {es-pull}61178[#61178] (issue: {es-issue}61177[#61177])

EQL::
* Return sequence join keys in the original type {es-pull}61268[#61268] (issue: {es-issue}59707[#59707])

Features/Data streams::
* "no such index [null]" when indexing into data stream with op_type=index [ISSUE] {es-pull}60581[#60581]
* Data streams: throw ResourceAlreadyExists exception {es-pull}60518[#60518]
* Track backing indices in data streams stats from cluster state {es-pull}59817[#59817]

Features/ILM+SLM::
* Fix race in SLM master/cluster state listeners {es-pull}59801[#59801]

Features/Ingest::
* Fix handling of final pipelines when destination is changed {es-pull}59522[#59522] (issue: {es-issue}57968[#57968])
* Fix wrong pipeline name in debug log {es-pull}58817[#58817] (issue: {es-issue}58478[#58478])
* Fix wrong result when executing bulk requests with and without pipeline {es-pull}60818[#60818] (issue: {es-issue}60437[#60437])
* Update regex file for es user agent node processor {es-pull}59697[#59697] (issue: {es-issue}59694[#59694])

IdentityProvider::
* Only call listener once (SP template registration) {es-pull}60497[#60497] (issues: {es-issue}54285[#54285], {es-issue}54423[#54423])

Machine Learning::
* Always write prediction_probability and prediction_score for classification inference {es-pull}60335[#60335]
* Ensure .ml-config index is updated before clearing anomaly job's finished_time {es-pull}61064[#61064] (issue: {es-issue}61157[#61157])
* Ensure annotations index mappings are up to date {es-pull}61107[#61107] (issue: {es-issue}74935[#74935])
* Handle node closed exception in ML result processing {es-pull}60238[#60238] (issue: {es-issue}60130[#60130])
* Recover data frame extraction search from latest sort key {es-pull}61544[#61544]

SQL::
* Fix NPE on ambiguous GROUP BY {es-pull}59370[#59370] (issues: {es-issue}46396[#46396], {es-issue}56489[#56489])
* Fix SYS COLUMNS schema in ODBC mode {es-pull}59513[#59513] (issue: {es-issue}59506[#59506])

Search::
* Disable sort optimization on search collapsing {es-pull}60838[#60838]
* Search fix: query_string regex searches not working on wildcard fields {es-pull}60959[#60959] (issue: {es-issue}60957[#60957])

Snapshot/Restore::
* Cleanly Handle S3 SDK Exceptions in Request Counting {es-pull}61686[#61686] (issue: {es-issue}61670[#61670])
* Fix Concurrent Snapshot Create+Delete + Delete Index {es-pull}61770[#61770] (issue: {es-issue}61762[#61762])



[[upgrade-7.9.1]]
[float]
=== Upgrades

Infra/Core::
* Upgrade to Lucene 8.6.2 {es-pull}61688[#61688] (issue: {es-issue}61512[#61512])



[[release-notes-7.9.0]]
== {es} version 7.9.0

Also see <<breaking-changes-7.9,Breaking changes in 7.9>>.

[float]
[[security-updates-7.9.0]]
=== Security updates

* A field disclosure flaw was found in {es} when running a scrolling search with
field level security. If a user runs the same query another more privileged user
recently ran, the scrolling search can leak fields that should be hidden. This
could result in an attacker gaining additional permissions against a restricted
index. All versions of {es} before 7.9.0 and 6.8.12 are affected by this flaw.
You must upgrade to {es} version 7.9.0 or 6.8.12 to obtain the fix.
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-7019[CVE-2020-7019]

[[known-issues-7.9.0]]
[discrete]
=== Known issues

* Upgrading to 7.9.0 from an earlier version will result in incorrect mappings
on the {ml} annotations index, and possibly also on the {ml} config index. This
will lead to some pages in the {ml} UI not displaying correctly, and may prevent
{ml-jobs} being created or updated. The best way to avoid this problem if you
read about this known issue before upgrading is to manually update the mappings
on these indices in your old {es} version _before_ upgrading to 7.9.0. If you
find out about the issue after upgrading then reindexing is required to recover.
Full details of the mitigations are in
{ml-docs}/ml-troubleshooting.html#ml-troubleshooting-mappings[Upgrade to 7.9.0 causes incorrect mappings].

* Lucene 8.6.0, on which Elasticsearch 7.9.0 is based,
  https://issues.apache.org/jira/browse/LUCENE-9478[contains a memory
  leak]. This memory leak manifests in Elasticsearch when a single document is
  updated repeatedly with a forced refresh. The cluster state storage layer in
  Elasticsearch is based on Lucene and does use single-document updates with
  forced refreshes, meaning that this memory leak manifests in Elasticsearch under
  normal conditions. It also manifests when user-controlled workloads update a
  single document in an index repeatedly with a forced refresh. In both cases,
  the memory leak is around 500 bytes per update, so it does take some time for
  the leak to show any meaningful impact on the system. Symptoms of this memory
  leak are the size of the used heap slowly rising over time, requests
  eventually being rejected by the real memory circuit breaker, and potentially
  out-of-memory errors. A workaround is to restart any nodes exhibiting these
  symptoms.  We are actively working with the Lucene community to release a
  https://github.com/apache/lucene-solr/pull/1779[fix] in Lucene 8.6.2 to
  deliver in Elasticsearch 7.9.1 that will address this memory leak.

[[breaking-7.9.0]]
[discrete]
=== Breaking changes

Script Cache::
* Script cache size and rate limiting are per-context {es-pull}55753[#55753] (issue: {es-issue}50152[#50152])

Field capabilities API::
* Constant_keyword fields are now described by their family type `keyword` instead of `constant_keyword` {es-pull}58483[#58483] (issue: {es-issue}53175[#53175])

Snapshot restore throttling::
* Restoring from a snapshot (which is a particular form of recovery) is now
  properly taking recovery throttling into account (i.e. the
  `indices.recovery.max_bytes_per_sec` setting).
  The `max_restore_bytes_per_sec` setting is also now defaulting to
  unlimited, whereas previously it was set to `40mb`, which is the
  default that's used for `indices.recovery.max_bytes_per_sec`. This means
  that no behavioral change will be observed by clusters where the recovery
  and restore settings had not been adapted from the defaults. {es-pull}58658[#58658]

Thread pool write queue size::
* The WRITE thread pool default queue size (`thread_pool.write.size`) has been
  increased from 200 to 10000. A small queue size (200) caused issues when users
  wanted to send small indexing requests with a high client count. Additional
  memory-oriented back pressure has been introduced with the
  `indexing_pressure.memory.limit` setting. This setting configures a limit to
  the number of bytes allowed to be consumed by outstanding indexing requests.
  {es-issue}59263[#59263]

Dangling indices::
* Automatically importing dangling indices is now deprecated, disabled by
  default, and will be removed in {es} 8.0. See the
  <<deprecate_auto_import_dangling_indices,migration notes>>.
  {es-pull}58176[#58176] {es-pull}58898[#58898] (issue: {es-issue}48366[#48366])

[[breaking-java-7.9.0]]
[discrete]
=== Breaking Java changes

Aggregations::
* Improve cardinality measure used to build aggs {es-pull}56533[#56533] (issue: {es-issue}56487[#56487])

Features/Ingest::
* Add optional description parameter to ingest processors. {es-pull}57906[#57906] (issue: {es-issue}56000[#56000])



[[feature-7.9.0]]
[discrete]
=== New features

Aggregations::
* Add moving percentiles pipeline aggregation {es-pull}55441[#55441] (issue: {es-issue}49452[#49452])
* Add normalize pipeline aggregation {es-pull}56399[#56399] (issue: {es-issue}51005[#51005])
* Add variable width histogram aggregation {es-pull}42035[#42035] (issues: {es-issue}9572[#9572], {es-issue}50863[#50863])
* Add pipeline inference aggregation {es-pull}58193[#58193]
* Speed up time interval arounding around daylight savings time (DST) {es-pull}56371[#56371] (issue: {es-issue}55559[#55559])

Geo::
* Override doc_value parameter in Spatial XPack module {es-pull}53286[#53286] (issue: {es-issue}37206[#37206])

Machine Learning::
* Add update data frame analytics jobs API {es-pull}58302[#58302] (issue: {es-issue}45720[#45720])
* Introduce model_plot_config.annotations_enabled setting for anomaly detection jobs {es-pull}57539[#57539] (issue: {es-issue}55781[#55781])
* Report significant changes to anomaly detection models in annotations of the results {ml-pull}1247[#1247], {es-pull}56342[#56342], {es-pull}56417[#56417], {es-pull}57144[#57144], {es-pull}57278[#57278], {es-pull}57539[#57539]

Mapping::
* Merge mappings for composable index templates {es-pull}58521[#58521] (issue: {es-issue}53101[#53101])
* Wildcard field optimised for wildcard queries {es-pull}49993[#49993] (issue: {es-issue}48852[#48852])

Search::
* Allow index filtering in field capabilities API {es-pull}57276[#57276] (issue: {es-issue}56195[#56195])



[[enhancement-7.9.0]]
[discrete]
=== Enhancements

Aggregations::
* Add support for numeric range keys {es-pull}56452[#56452] (issue: {es-issue}56402[#56402])
* Added standard deviation / variance sampling to extended stats {es-pull}49782[#49782] (issue: {es-issue}49554[#49554])
* Give significance lookups their own home {es-pull}57903[#57903]
* Increase search.max_buckets to 65,535 {es-pull}57042[#57042] (issue: {es-issue}51731[#51731])
* Optimize date_histograms across daylight savings time {es-pull}55559[#55559]
* Return clear error message if aggregation type is invalid {es-pull}58255[#58255] (issue: {es-issue}58146[#58146])
* Save memory on numeric significant terms when not top {es-pull}56789[#56789] (issue: {es-issue}55873[#55873])
* Save memory when auto_date_histogram is not on top {es-pull}57304[#57304] (issue: {es-issue}56487[#56487])
* Save memory when date_histogram is not on top {es-pull}56921[#56921] (issues: {es-issue}55873[#55873], {es-issue}56487[#56487])
* Save memory when histogram agg is not on top {es-pull}57277[#57277]
* Save memory when numeric terms agg is not top {es-pull}55873[#55873]
* Save memory when parent and child are not on top {es-pull}57892[#57892] (issue: {es-issue}55873[#55873])
* Save memory when rare_terms is not on top {es-pull}57948[#57948] (issue: {es-issue}55873[#55873])
* Save memory when significant_text is not on top {es-pull}58145[#58145] (issue: {es-issue}55873[#55873])
* Save memory when string terms are not on top {es-pull}57758[#57758]
* Speed up reducing auto_date_histo with a time zone {es-pull}57933[#57933] (issue: {es-issue}56124[#56124])
* Speed up rounding in auto_date_histogram {es-pull}56384[#56384] (issue: {es-issue}55559[#55559])

Allocation::
* Account for remaining recovery in disk allocator {es-pull}58029[#58029]

Analysis::
* Add max_token_length setting to the CharGroupTokenizer {es-pull}56860[#56860] (issue: {es-issue}56676[#56676])
* Expose discard_compound_token option to kuromoji_tokenizer {es-pull}57421[#57421]
* Support multiple tokens on LHS in stemmer_override rules (#56113) {es-pull}56484[#56484] (issue: {es-issue}56113[#56113])

Authentication::
* Add http proxy support for OIDC realm {es-pull}57039[#57039] (issue: {es-issue}53379[#53379])
* Improve threadpool usage and error handling for API key validation {es-pull}58090[#58090] (issue: {es-issue}58088[#58088])
* Support handling LogoutResponse from SAML idP {es-pull}56316[#56316] (issues: {es-issue}40901[#40901], {es-issue}43264[#43264])

Authorization::
* Add cache for application privileges {es-pull}55836[#55836] (issue: {es-issue}54317[#54317])
* Add monitor and view_index_metadata privileges to built-in `kibana_system` role {es-pull}57755[#57755]
* Improve role cache efficiency for API key roles {es-pull}58156[#58156] (issue: {es-issue}53939[#53939])

CCR::
* Allow follower indices to override leader settings {es-pull}58103[#58103]

CRUD::
* Retry failed replication due to transient errors {es-pull}55633[#55633]

Engine::
* Don't log on RetentionLeaseSync error handler after an index has been deleted {es-pull}58098[#58098] (issue: {es-issue}57864[#57864])

Features/Data streams::
* Add support for snapshot and restore to data streams {es-pull}57675[#57675] (issues: {es-issue}53100[#53100], {es-issue}57127[#57127])
* Data stream creation validation allows for prefixed indices {es-pull}57750[#57750] (issue: {es-issue}53100[#53100])
* Disallow deletion of composable template if in use by data stream {es-pull}57957[#57957] (issue: {es-issue}57004[#57004])
* Validate alias operations don't target data streams {es-pull}58327[#58327] (issue: {es-issue}53100[#53100])

Features/ILM+SLM::
* Add data stream support to searchable snapshot action {es-pull}57873[#57873] (issue: {es-issue}53100[#53100])
* Add data stream support to the shrink action {es-pull}57616[#57616] (issue: {es-issue}53100[#53100])
* Add support for rolling over data streams  {es-pull}57295[#57295] (issues: {es-issue}53100[#53100], {es-issue}53488[#53488])
* Check the managed index is not a data stream write index {es-pull}58239[#58239] (issue: {es-issue}53100[#53100])

Features/Indices APIs::
* Add default composable templates for new indexing strategy {es-pull}57629[#57629] (issue: {es-issue}56709[#56709])
* Add index block api {es-pull}58094[#58094]
* Add new flag to check whether alias exists on remove {es-pull}58100[#58100]
* Add prefer_v2_templates parameter to reindex {es-pull}56253[#56253] (issue: {es-issue}53101[#53101])
* Add template simulation API for simulating template composition {es-pull}56842[#56842] (issues: {es-issue}53101[#53101], {es-issue}55686[#55686], {es-issue}56255[#56255], {es-issue}56390[#56390])

Features/Ingest::
* Add ignore_empty_value parameter in set ingest processor {es-pull}57030[#57030] (issue: {es-issue}54783[#54783])
* Support `if_seq_no` and `if_primary_term` for ingest {es-pull}55430[#55430] (issue: {es-issue}41255[#41255])

Features/Java High Level REST Client::
* Add support for data streams {es-pull}58106[#58106] (issue: {es-issue}53100[#53100])
* Enable decompression of response within LowLevelRestClient {es-pull}55413[#55413] (issues: {es-issue}24349[#24349], {es-issue}53555[#53555])

Features/Java Low Level REST Client::
* Add isRunning method to RestClient {es-pull}57973[#57973] (issue: {es-issue}42133[#42133])
* Add RequestConfig support to RequestOptions {es-pull}57972[#57972]

Infra/Circuit Breakers::
* Enhance real memory circuit breaker with G1 GC {es-pull}58674[#58674] (issue: {es-issue}57202[#57202])

Infra/Core::
* Introduce node.roles setting {es-pull}54998[#54998]

Infra/Packaging::
* Remove DEBUG-level logging from actions in Docker {es-pull}57389[#57389] (issues: {es-issue}51198[#51198], {es-issue}51459[#51459])

Infra/Plugins::
* Improved ExtensiblePlugin {es-pull}58234[#58234]

Infra/Resiliency::
* Adds resiliency to read-only filesystems #45286 {es-pull}52680[#52680] (issue: {es-issue}45286[#45286])

Machine Learning::
* Accounting for model size when models are not cached. {es-pull}58670[#58670]
* Adds new for_export flag to GET _ml/inference API {es-pull}57351[#57351]
* Adds WKT geometry detection in find_file_structure {es-pull}57014[#57014] (issue: {es-issue}56967[#56967])
* Calculate cache misses for inference and return in stats {es-pull}58252[#58252]
* Delete auto-generated annotations when job is deleted. {es-pull}58169[#58169] (issue: {es-issue}57976[#57976])
* Delete auto-generated annotations when model snapshot is reverted {es-pull}58240[#58240] (issue: {es-issue}57982[#57982])
* Delete expired data by job {es-pull}57337[#57337]
* Introduce Annotation.event field {es-pull}57144[#57144] (issue: {es-issue}55781[#55781])
* Add support for larger forecasts in memory via max_model_memory setting {ml-pull}1238[#1238], {es-pull}57254[#57254]
* Don't lose precision when saving model state {ml-pull}1274[#1274]
* Parallelize the feature importance calculation for classification and regression over trees {ml-pull}1277[#1277]
* Add an option to do categorization independently for each partition {ml-pull}1293[#1293], {ml-pull}1318[#1318], {ml-pull}1356[#1356], {es-pull}57683[#57683]
* Memory usage is reported during job initialization {ml-pull}1294[#1294]
* More realistic memory estimation for classification and regression means that these analyses will require lower memory limits than before {ml-pull}1298[#1298]
* Checkpoint state to allow efficient failover during coarse parameter search for classification and regression {ml-pull}1300[#1300]
* Improve data access patterns to speed up classification and regression {ml-pull}1312[#1312]
* Performance improvements for classification and regression, particularly running multithreaded {ml-pull}1317[#1317]
* Improve runtime and memory usage training deep trees for classification and regression {ml-pull}1340[#1340]
* Improvement in handling large inference model definitions {ml-pull}1349[#1349]
* Add a peak_model_bytes field to model_size_stats {ml-pull}1389[#1389]

Mapping::
* Add regex query support to wildcard field {es-pull}55548[#55548] (issue: {es-issue}54725[#54725])
* Make `keyword` a family of field types {es-pull}58315[#58315] (issue: {es-issue}53175[#53175])
* Store parsed mapping settings in IndexSettings {es-pull}57492[#57492] (issue: {es-issue}57395[#57395])
* Wildcard field - add support for custom null values {es-pull}57047[#57047]

Network::
* Make the number of transport threads equal to the number of available CPUs {es-pull}56488[#56488]

Recovery::
* Implement dangling indices API {es-pull}50920[#50920] (issue: {es-issue}48366[#48366])
* Reestablish peer recovery after network errors {es-pull}55274[#55274]
* Sending operations concurrently in peer recovery {es-pull}58018[#58018] (issue: {es-issue}58011[#58011])

Reindex::
* Throw an illegal_argument_exception when max_docs is less than slices {es-pull}54901[#54901] (issue: {es-issue}52786[#52786])

SQL::
* Implement TIME_PARSE function for parsing strings into TIME values {es-pull}55223[#55223] (issues: {es-issue}54963[#54963], {es-issue}55095[#55095])
* Implement TOP as an alternative to LIMIT {es-pull}57428[#57428] (issue: {es-issue}41195[#41195])
* Implement TRIM function {es-pull}57518[#57518] (issue: {es-issue}41195[#41195])
* Improve performances of LTRIM/RTRIM {es-pull}57603[#57603] (issue: {es-issue}57594[#57594])
* Make CASTing string to DATETIME more lenient {es-pull}57451[#57451]
* Redact credentials in connection exceptions {es-pull}58650[#58650] (issue: {es-issue}56474[#56474])
* Relax parsing of date/time escaped literals {es-pull}58336[#58336] (issue: {es-issue}58262[#58262])
* Add support for scalars within LIKE/RLIKE {es-pull}56495[#56495] (issue: {es-issue}55058[#55058])

Search::
* Add description to submit and get async search, as well as cancel tasks {es-pull}57745[#57745]
* Add matchBoolPrefix static method in query builders {es-pull}58637[#58637] (issue: {es-issue}58388[#58388])
* Add range query support to wildcard field {es-pull}57881[#57881] (issue: {es-issue}57816[#57816])
* Group docIds by segment in FetchPhase to better use LRU cache {es-pull}57273[#57273]
* Improve error handling when decoding async execution ids {es-pull}56285[#56285]
* Specify reason whenever async search gets cancelled {es-pull}57761[#57761]
* Use index sort range query when possible. {es-pull}56657[#56657] (issue: {es-issue}48665[#48665])

Security::
* Add machine learning admin permissions to the kibana_system role {es-pull}58061[#58061]
* Just log 401 stacktraces {es-pull}55774[#55774]

Snapshot/Restore::
* Deduplicate Index Metadata in BlobStore {es-pull}50278[#50278] (issues: {es-issue}45736[#45736], {es-issue}46250[#46250], {es-issue}49800[#49800])
* Default to zero replicas for searchable snapshots {es-pull}57802[#57802] (issue: {es-issue}50999[#50999])
* Enable fully concurrent snapshot operations {es-pull}56911[#56911]
* Support cloning of searchable snapshot indices {es-pull}56595[#56595]
* Track GET/LIST Azure Storage API calls  {es-pull}56773[#56773]
* Track GET/LIST GoogleCloudStorage API calls {es-pull}56585[#56585]
* Track PUT/PUT_BLOCK operations on AzureBlobStore. {es-pull}56936[#56936]
* Track multipart/resumable uploads GCS API calls {es-pull}56821[#56821]
* Track upload requests on S3 repositories {es-pull}56826[#56826]

Task Management::
* Add index name to refresh mapping task {es-pull}57598[#57598]
* Cancel task and descendants on channel disconnects {es-pull}56620[#56620] (issues: {es-issue}56327[#56327], {es-issue}56619[#56619])

Transform::
* Add support for terms agg in transforms {es-pull}56696[#56696]
* Adds geotile_grid support in group_by {es-pull}56514[#56514] (issue: {es-issue}56121[#56121])



[[bug-7.9.0]]
[discrete]
=== Bug fixes

Aggregations::
* Fix auto_date_histogram interval {es-pull}56252[#56252] (issue: {es-issue}56116[#56116])
* Fix bug in faster interval rounding {es-pull}56433[#56433] (issue: {es-issue}56400[#56400])
* Fix bug in parent and child aggregators when parent field not defined {es-pull}57089[#57089] (issue: {es-issue}42997[#42997])
* Fix missing null values for std_deviation_bounds in ext. stats aggs {es-pull}58000[#58000]

Allocation::
* Reword INDEX_READ_ONLY_ALLOW_DELETE_BLOCK message {es-pull}58410[#58410] (issues: {es-issue}42559[#42559], {es-issue}50166[#50166], {es-issue}58376[#58376])

Authentication::
* Map only specific type of OIDC Claims {es-pull}58524[#58524]

Authorization::
* Change privilege of enrich stats API to monitor {es-pull}52027[#52027] (issue: {es-issue}51677[#51677])

Engine::
* Fix local translog recovery not updating safe commit in edge case {es-pull}57350[#57350] (issue: {es-issue}57010[#57010])
* Hide AlreadyClosedException on IndexCommit release {es-pull}57986[#57986] (issue: {es-issue}57797[#57797])

Features/ILM+SLM::
* Normalized prefix for rollover API {es-pull}57271[#57271] (issue: {es-issue}53388[#53388])

Features/Indices APIs::
* Don't allow invalid template combinations {es-pull}56397[#56397] (issues: {es-issue}53101[#53101], {es-issue}56314[#56314])
* Handle `cluster.max_shards_per_node` in YAML config {es-pull}57234[#57234] (issue: {es-issue}40803[#40803])

Features/Ingest::
* Fix ingest simulate verbose on failure with conditional {es-pull}56478[#56478] (issue: {es-issue}56004[#56004])

Geo::
* Check for degenerated lines when calculating the centroid {es-pull}58027[#58027] (issue: {es-issue}55851[#55851])
* Fix bug in circuit-breaker check for geoshape grid aggregations {es-pull}57962[#57962] (issue: {es-issue}57847[#57847])

Infra/Scripting::
* Fix source return bug in scripting {es-pull}56831[#56831] (issue: {es-issue}52103[#52103])

Machine Learning::
* Fix wire serialization for flush acknowledgements {es-pull}58413[#58413]
* Make waiting for renormalization optional for internally flushing job {es-pull}58537[#58537] (issue: {es-issue}58395[#58395])
* Tail the C++ logging pipe before connecting other pipes {es-pull}56632[#56632] (issue: {es-issue}56366[#56366])
* Fix numerical issues leading to blow up of the model plot bounds {ml-pull}1268[#1268]
* Fix causes for inverted forecast confidence interval bounds {ml-pull}1369[#1369] (issue: {ml-issue}1357[#1357])
* Restrict growth of max matching string length for categories {ml-pull}1406[#1406]

Mapping::
* Wildcard field fix for scripts - changed value type from BytesRef to String  {es-pull}58060[#58060] (issue: {es-issue}58044[#58044])

SQL::
* Introduce JDBC option for meta pattern escaping {es-pull}40661[#40661] (issue: {es-issue}40640[#40640])

Search::
* Don't omit empty arrays when filtering _source {es-pull}56527[#56527] (issues: {es-issue}20736[#20736], {es-issue}22593[#22593], {es-issue}23796[#23796])
* Fix casting of scaled_float in sorts {es-pull}57207[#57207]

Snapshot/Restore::
* Account for recovery throttling when restoring snapshot {es-pull}58658[#58658] (issue: {es-issue}57023[#57023])
* Fix noisy logging during snapshot delete {es-pull}56264[#56264]
* Fix S3ClientSettings leak {es-pull}56703[#56703] (issue: {es-issue}56702[#56702])



[[upgrade-7.9.0]]
[discrete]
=== Upgrades

Search::
* Update to lucene snapshot e7c625430ed {es-pull}57981[#57981]
