AWS OpenSearch 2.2.0 已经在开发中，OpenSearch 是 AWS 自 Elasticsearch 7.10.2 的开源搜索和分析引擎。

该版本改进内容包括：

Features/Enhancements

• Task consumer Integration (#2293) (#4141)
• [Backport 2.x] [Segment Replication] Add SegmentReplicationTargetService to orchestrate replication events. (#4074)
• Support task resource tracking in OpenSearch (#3982) (#4087)
• Making shard copy count a multiple of attribute count (#3462) (#4086)
• [Backport 2.x] [Segment Rreplication] Adding CheckpointRefreshListener to trigger when Segment replication is turned on and Primary shard refreshes (#4044)
• Add doc_count field mapper (#3985) (#4037)
• Parallelize stale blobs deletion during snapshot delete (#3796) (#3990)
• [Backport 2.x] [Segment Replication] Add a new Engine implementation for replicas with segment replication enabled. (#4003)
• [Backport 2.x] Adds a new parameter, max_analyzer_offset, for the highlighter (#4031)
• Update merge on refresh and merge on commit defaults in Opensearch (Lucene 9.3) (#3561) (#4013)
• Make HybridDirectory MMAP Extensions Configurable (#3837) (#3970)
• Add option to disable chunked transfer-encoding (#3864) (#3885)
• Introducing TranslogManager implementations decoupled from the Engine [2.x] (#3820)
• Changing default no_master_block from write to metadata_write (#3621) (#3756)

Bug Fixes

• OpenSearch crashes on closed client connection before search reply when total ops higher compared to expected (#4143) (#4145)
• Binding empty instance of SegmentReplicationCheckpointPublisher when Feature Flag is off in IndicesModule.java file. (#4119)
• Fix the bug that masterOperation(with task param) is bypassed (#4103) (#4115)
• Fixing flaky org.opensearch.cluster.routing.allocation.decider.DiskThresholdDeciderIT.testHighWatermarkNotExceeded test case (#4012) (#4014)
• Correct typo: Rutime -> Runtime (#3896) (#3898)
• Fixing implausibly old time stamp 1970-01-01 00:00:00 by using the timestamp from the Git revision instead of default 0 value (#3883) (#3891)

Infrastructure

• Correctly ignore depandabot branches during push (#4077) (#4113)
• Build performance improvements (#3926) (#3937)
• PR coverage requirement and default settings (#3931) (#3938)
• [Backport 2.x] Fail build on wildcard imports (#3940)
• Don't run EmptyDirTaskTests in a Docker container (#3792) (#3912)
• Add coverage, gha, jenkins server, documentation and forum badges (#3886)
• Unable to use Systemd module with tar distribution (#3755) (#3903)
• Ignore backport / autocut / dependentbot branches for gradle checks (#3816) (#3825)
• Setup branch push coverage and fix coverage uploads (#3793) (#3811)
• Enable XML test reports for Jenkins integration (#3799) (#3803)

Maintenance

• OpenJDK Update (July 2022 Patch releases) (#4023) (#4092)
• Update to Lucene 9.3.0 (#4043) (#4088)
• Bump commons-configuration2 from 2.7 to 2.8.0 in /plugins/repository-hdfs (#3764) (#3783)
• Use bash in systemd-entrypoint shebang (#4008) (#4009)
• Bump com.gradle.enterprise from 3.10.1 to 3.10.2 (#3568) (#3934)
• Bump log4j-core in /buildSrc/src/testKit/thirdPartyAudit/sample_jars (#3763) (#3784)
• Added bwc version 1.3.5 (#3911) (#3913)
• Update to Gradle 7.5 (#3594) (#3904)
• Update Netty to 4.1.79.Final (#3868) (#3874)
• Upgrade MinIO image version (#3541) (#3867)
• Add netty-transport-native-unix-common to modules/transport-netty4/bu… (#3848) (#3853)
• Update outdated dependencies (#3821) (#3854)
• Added bwc version 2.1.1 (#3806)
• Upgrade netty from 4.1.73.Final to 4.1.78.Final (#3772) (#3778)
• Bump protobuf-java from 3.21.1 to 3.21.2 in /plugins/repository-hdfs (#3711) (#3726)
• Upgrading AWS SDK dependency for native plugins (#3694) (#3701)

Refactoring

• [Backport 2.x] Changes to encapsulate Translog into TranslogManager (#4095) (#4142)
• Deprecate and rename abstract methods in interfaces that contain 'master' in name (#4121) (#4123)
• [Backport 2.x] Integrate Engine with decoupled Translog interfaces (#3822)
• Deprecate class FakeThreadPoolMasterService, BlockMasterServiceOnMaster and BusyMasterServiceDisruption (#4058) (#4068)
• Rename classes with name 'MasterService' to 'ClusterManagerService' in directory 'test/framework' (#4051) (#4057)
• Deprecate class 'MasterService' and create alternative class 'ClusterManagerService' (#4022) (#4050)
• Deprecate and Rename abstract methods from 'Master' terminology to 'ClusterManager'. (#4032) (#4048)
• Deprecate public methods and variables that contain 'master' terminology in class 'NoMasterBlockService' and 'MasterService' (#4006) (#4038)
• Deprecate public methods and variables that contain 'master' terminology in 'client' directory (#3966) (#3981)
• [segment replication]Introducing common Replication interfaces for segment replication and recovery code paths (#3234) (#3984)
• Deprecate public methods and variables that contain 'master' terminology in 'test/framework' directory (#3978) (#3987)
• [Backport 2.x] [Segment Replication] Moving RecoveryState.Index to a top-level class and renaming (#3971)
• Rename and deprecate public methods that contains 'master' in the name in 'server' directory (#3647) (#3964)
• [2.x] Deprecate public class names with master terminology (#3871) (#3914)
• [Backport 2.x] Rename public classes with 'Master' to 'ClusterManager' (#3870)
• Revert renaming masterOperation() to clusterManagerOperation() (#3681) (#3714)
• Revert renaming method onMaster() and offMaster() in interface LocalNodeMasterListener (#3686) (#3693)

详细每个版本的改进内容请看

https://gitee.com/mirrors/OpenSearch-Project/tree/main/release-note