* Incompatible with previous releases when use H2/MySQL/TiDB storage options, due to support multiple alarm rules triggered for one entity.
* Chore: adapt `create_source_release.sh` to make it runnable on Linux.
* Add `package` to `.proto` files, prevent polluting top-level namespace in some languages; The OAP server supports previous agent releases, whereas the previous OAP server (<=8.3.0)won'trecognizeneweragentssincethisversion(>= 8.4.0).
* Add ElasticSearch 7.10 to test matrix and verify it works.
* Replace Apache RAT with skywalking-eyes to check license headers.
* Set up test of Envoy ALS / MetricsService under Istio 1.8.2 to verify Envoy V3 protocol
* Test: fix flaky E2E test of Kafka.
#### Java Agent
* The operation name of quartz-scheduler plugin, has been changed as the `quartz-scheduler/${className}` format.
* Fix jdk-http and okhttp-3.x plugin did not overwrite the old trace header.
* Add interceptors of method(analyze, searchScroll, clearScroll, searchTemplate and deleteByQuery) for elasticsearch-6.x-plugin.
* Fix the unexpected RunningContext recreation in the Tomcat plugin.
* Fix the potential NPE when trace_sql_parameters is enabled.
* Update `byte-buddy` to 1.10.19.
* Fix thrift plugin trace link broken when intermediate service does not mount agent
* Fix thrift plugin collects wrong args when the method without parameter.
* Fix DataCarrier's `org.apache.skywalking.apm.commons.datacarrier.buffer.Buffer` implementation isn't activated in `IF_POSSIBLE` mode.
* Fix ArrayBlockingQueueBuffer's useless `IF_POSSIBLE` mode list
* Support building gRPC TLS channel but CA file is not required.
* Add witness method mechanism in the agent plugin core.
* Add Dolphinscheduler plugin definition.
* Make sampling still works when the trace ignores plug-in activation.
* Fix mssql-plugin occur ClassCastException when call the method of return generate key.
* The operation name of dubbo and dubbo-2.7.x-plugin, has been changed as the `groupValue/className.methodName` format
* Fix thread leaks caused by the elasticsearch-6.x-plugin plugin.
* Support reading segmentId and spanId with toolkit.
* Fix RestTemplate plugin recording url tag with wrong port
* Support collecting logs and forwarding through gRPC.
* Support config `agent.sample_n_per_3_secs` can be changed in the runtime.
* Support config `agent.ignore_suffix` can be changed in the runtime.
* Support DNS periodic resolving mechanism to update backend service.
* Support config `agent.trace.ignore_path` can be changed in the runtime.
* Added support for transmitting logback 1.x and log4j 2.x formatted & un-formatted messages via gPRC
#### OAP-Backend
* Make meter receiver support MAL.
* Support influxDB connection response format option. Fix some error when use JSON as influxDB response format.
* Support Kafka MirrorMaker 2.0 to replicate topics between Kafka clusters.
* Add the rule name field to alarm record storage entity as a part of ID, to support multiple alarm rules triggered for one entity. The scope id has been removed from the ID.
* Fix MAL concurrent execution issues.
* Fix group name can't be queried in the GraphQL.
* Fix potential gRPC connection leak(not closed) for the channels among OAP instances.
* Filter OAP instances(unassigned in booting stage) of the empty IP in KubernetesCoordinator.
* Add component ID for Python aiohttp plugin requester and server.
* Fix H2 in-memory database table missing issues
* Add component ID for Python pyramid plugin server.
* Add component ID for NodeJS Axios plugin.
* Fix searchService method error in storage-influxdb-plugin.
* Add JavaScript component ID.
* Fix CVE of UninstrumentedGateways in Dynamic Configuration activation.
* Improve query performance in storage-influxdb-plugin.
* Fix the uuid field in GRPCConfigWatcherRegister is not updated.
* Support Envoy {AccessLog,Metrics}Service API V3.
* Adopt the [MAL](docs/en/concepts-and-designs/mal.md) in Envoy metrics service analyzer.
* Fix the priority setting doesn't work of the ALS analyzers.
* Fix bug that `endpoint-name-grouping.yml` is not customizable in Dockerized case.
* Fix bug that istio version metric type on UI template mismatches the otel rule.
* Incompatible with previous releases when use H2/MySQL/TiDB storage options, due to support multiple alarm rules triggered for one entity.
* Chore: adapt `create_source_release.sh` to make it runnable on Linux.
* Add `package` to `.proto` files, prevent polluting top-level namespace in some languages; The OAP server supports previous agent releases, whereas the previous OAP server (<=8.3.0)won'trecognizeneweragentssincethisversion(>= 8.4.0).
* Add ElasticSearch 7.10 to test matrix and verify it works.
* Replace Apache RAT with skywalking-eyes to check license headers.
* Set up test of Envoy ALS / MetricsService under Istio 1.8.2 to verify Envoy V3 protocol
* Test: fix flaky E2E test of Kafka.
#### Java Agent
* The operation name of quartz-scheduler plugin, has been changed as the `quartz-scheduler/${className}` format.
* Fix jdk-http and okhttp-3.x plugin did not overwrite the old trace header.
* Add interceptors of method(analyze, searchScroll, clearScroll, searchTemplate and deleteByQuery) for elasticsearch-6.x-plugin.
* Fix the unexpected RunningContext recreation in the Tomcat plugin.
* Fix the potential NPE when trace_sql_parameters is enabled.
* Update `byte-buddy` to 1.10.19.
* Fix thrift plugin trace link broken when intermediate service does not mount agent
* Fix thrift plugin collects wrong args when the method without parameter.
* Fix DataCarrier's `org.apache.skywalking.apm.commons.datacarrier.buffer.Buffer` implementation isn't activated in `IF_POSSIBLE` mode.
* Fix ArrayBlockingQueueBuffer's useless `IF_POSSIBLE` mode list
* Support building gRPC TLS channel but CA file is not required.
* Add witness method mechanism in the agent plugin core.
* Add Dolphinscheduler plugin definition.
* Make sampling still works when the trace ignores plug-in activation.
* Fix mssql-plugin occur ClassCastException when call the method of return generate key.
* The operation name of dubbo and dubbo-2.7.x-plugin, has been changed as the `groupValue/className.methodName` format
* Fix thread leaks caused by the elasticsearch-6.x-plugin plugin.
* Support reading segmentId and spanId with toolkit.
* Fix RestTemplate plugin recording url tag with wrong port
* Support collecting logs and forwarding through gRPC.
* Support config `agent.sample_n_per_3_secs` can be changed in the runtime.
* Support config `agent.ignore_suffix` can be changed in the runtime.
* Support DNS periodic resolving mechanism to update backend service.
* Support config `agent.trace.ignore_path` can be changed in the runtime.
* Added support for transmitting logback 1.x and log4j 2.x formatted & un-formatted messages via gPRC
#### OAP-Backend
* Make meter receiver support MAL.
* Support influxDB connection response format option. Fix some error when use JSON as influxDB response format.
* Support Kafka MirrorMaker 2.0 to replicate topics between Kafka clusters.
* Add the rule name field to alarm record storage entity as a part of ID, to support multiple alarm rules triggered for one entity. The scope id has been removed from the ID.
* Fix MAL concurrent execution issues.
* Fix group name can't be queried in the GraphQL.
* Fix potential gRPC connection leak(not closed) for the channels among OAP instances.
* Filter OAP instances(unassigned in booting stage) of the empty IP in KubernetesCoordinator.
* Add component ID for Python aiohttp plugin requester and server.
* Fix H2 in-memory database table missing issues
* Add component ID for Python pyramid plugin server.
* Add component ID for NodeJS Axios plugin.
* Fix searchService method error in storage-influxdb-plugin.
* Add JavaScript component ID.
* Fix CVE of UninstrumentedGateways in Dynamic Configuration activation.
* Improve query performance in storage-influxdb-plugin.
* Fix the uuid field in GRPCConfigWatcherRegister is not updated.
* Support Envoy {AccessLog,Metrics}Service API V3.
* Adopt the [MAL](docs/en/concepts-and-designs/mal.md) in Envoy metrics service analyzer.
* Fix the priority setting doesn't work of the ALS analyzers.
* Fix bug that `endpoint-name-grouping.yml` is not customizable in Dockerized case.
* Fix bug that istio version metric type on UI template mismatches the otel rule.