⚠️ Noteworthy

• Replace the OpenTelemetry protobuf library #5658
• Add config option to compress Datadog payload #2297

⭐ New Features

• Optimize PrometheusMeterRegistry and MicrometerCollector snapshot collection #7802
• Skip registering JCache meters when statistics are not enabled #7562
• Fail collision validation at registration instead of at scrape with typed Prometheus family descriptors #7487
• Prometheus: unnecessary allocation and validation performed on every scrape #7450
• Bump Kotlin target from 1.8 to 2.0 #7338
• Add option for time-based FunctionCounter #7329
• Remove lastScope field and deprecated implementations from SimpleObservation #7273
• Replace the OpenTelemetry protobuf library #5658
• KeyValue support for Observation.Event #5238
• Add config option to compress Datadog payload #2297

🐞 Bug Fixes

• OTLP publishing fails if a cumulative LongTaskTimer present with a histogram #7830
• Race condition in registry searching and MeterNotFoundException creation may result in a failure that looks as if it should have succeeded #2307
• ClassNotFoundException: org.LatencyUtils.PauseDetector is thrown when introspecting AbstractTimer #7815
• Prometheus custom meters: creation timestamps are incorrect #7798
• Fix memory leak/NPE in MicrometerHttpClientInterceptor (HC4 & HC5)
• Sanitize line terminators in Dogstatsd, Etsy StatsD, and LoggingMeterRegistry

🔨 Dependency Upgrades

• Bump io.netty:netty-bom from 4.2.15.Final to 4.2.17.Final #7819
• Bump software.amazon.awssdk:cloudwatch from 2.46.5 to 2.51.3 #7818
• Bump com.google.cloud:libraries-bom from 26.83.0 to 26.86.0 #7794
• Bump com.google.auth:google-auth-library-oauth2-http from 1.48.0 to 1.50.0 #7793
• Bump com.google.cloud:google-cloud-monitoring from 3.94.0 to 3.96.0 #7790
• Bump com.netflix.spectator:spectator-reg-atlas from 1.9.9 to 1.10.5 #7792
• Bump org.jetbrains.kotlinx:kotlinx-coroutines-core from 1.7.3 to 1.11.0 #7476
• Bump io.prometheus:prometheus-metrics-bom from 1.7.0 to 1.8.0 #7615

📝 Tasks

• Add sample to print out OTLP output in a human readable format #7832
• Fix ineffective ExemplarSampler cache in DefaultExemplarSamplerFactory #7657
• Note micrometer-jetty11 deprecation in the artifact description #7651

❤️ Contributors

Thank you to all the contributors who worked on this release:

@arimu1, @kalayciburak, @antonio-pedro99, @jewoodev, @zeitlinger, @schiemon, and @m-burst

🐞 Bug Fixes

• ClassNotFoundException: org.LatencyUtils.PauseDetector is thrown when introspecting AbstractTimer #7815
• Prometheus custom meters: creation timestamps are incorrect #7798
• Fix memory leak/NPE in MicrometerHttpClientInterceptor (HC4 & HC5)
• Sanitize line terminators in Dogstatsd, Etsy StatsD, and LoggingMeterRegistry

🔨 Dependency Upgrades

• Bump io.netty:netty-bom from 4.2.15.Final to 4.2.17.Final #7822
• Bump software.amazon.awssdk:cloudwatch from 2.46.6 to 2.46.21 #7705

📝 Tasks

• Fix ineffective ExemplarSampler cache in DefaultExemplarSamplerFactory #7657
• Note micrometer-jetty11 deprecation in the artifact description #7651

❤️ Contributors

Thank you to all the contributors who worked on this release:
@arimu1, @kalayciburak

🐞 Bug Fixes

• Prometheus custom meters: creation timestamps are incorrect #7798
• Fix memory leak/NPE in MicrometerHttpClientInterceptor (HC4 & HC5)
• Sanitize line terminators in Dogstatsd, Etsy StatsD, and LoggingMeterRegistry

🔨 Dependency Upgrades

• Bump io.netty:netty-bom from 4.1.135.Final to 4.1.137.Final #7823

📝 Tasks

• Fix ineffective ExemplarSampler cache in DefaultExemplarSamplerFactory #7657
• Note micrometer-jetty11 deprecation in the artifact description #7651

❤️ Contributors

Thank you to all the contributors who worked on this release:
@arimu1

See also the 1.17 migration guide and the release notes for 1.17.0-RC1, 1.17.0-M3, 1.17.0-M2, 1.17.0-M1.

🐞 Bug Fixes

• ArrayIndexOutOfBoundsException when using LongTaskTimer #3877
• Jetty 12's TimedHandler marks some requests with outcome UNKNOWN #7276
• MeterRegistry closes HighCardinalityTagsDetector twice if the registry is closed twice #7409
• Reduce allocation in HTTP server instrumentation #7580
• Reduce allocation in gRPC server convention #7581

📔 Documentation

• Clarify time series produced by LongTaskTimer when using Prometheus #6507
• Document metrics that need to close the MeterBinder #4624
• Multigauge Documentation lacks overwrite=true #4403

🔨 Dependency Upgrades

• Bump com.dynatrace.metric.util:dynatrace-metric-utils-java from 2.4.0 to 2.5.0 #7452
• Bump com.google.auth:google-auth-library-oauth2-http from 1.43.0 to 1.48.0 #7397
• Bump com.google.cloud:google-cloud-monitoring from 3.89.0 to 3.94.0 #7398
• Bump com.google.cloud:libraries-bom from 26.79.0 to 26.83.0 #7497
• Bump com.netflix.spectator:spectator-reg-atlas from 1.9.6 to 1.9.9 #7552
• Bump dropwizard-metrics from 4.2.38 to 4.2.39 #7527
• Bump io.prometheus:prometheus-metrics-bom from 1.5.1 to 1.7.0 #7572
• Bump software.amazon.awssdk:cloudwatch from 2.42.32 to 2.46.4 #7494

❤️ Contributors

Thank you to all the contributors who worked on this release:

@blaspat, @codingkiddo, @izeye, @jewoodev, and @schiemon

🐞 Bug Fixes

• ArrayIndexOutOfBoundsException when using LongTaskTimer #3877
• Jetty 12's TimedHandler marks some requests with outcome UNKNOWN #7276
• MeterRegistry closes HighCardinalityTagsDetector twice if the registry is closed twice #7409
• Reduce allocation in HTTP server instrumentation #7580
• Reduce allocation in gRPC server convention #7581

📔 Documentation

• Clarify time series produced by LongTaskTimer when using Prometheus #6507
• Document metrics that need to close the MeterBinder #4624
• Multigauge Documentation lacks overwrite=true #4403

🔨 Dependency Upgrades

• Bump com.netflix.spectator:spectator-reg-atlas from 1.9.6 to 1.9.9 #7552
• Bump dropwizard-metrics from 4.2.38 to 4.2.39 #7527

❤️ Contributors

Thank you to all the contributors who worked on this release:

@blaspat, @codingkiddo, @izeye, @jewoodev, and @schiemon

🐞 Bug Fixes

• ArrayIndexOutOfBoundsException when using LongTaskTimer #3877
• Jetty 12's TimedHandler marks some requests with outcome UNKNOWN #7276
• MeterRegistry closes HighCardinalityTagsDetector twice if the registry is closed twice #7409
• Reduce allocation in HTTP server instrumentation #7580
• Reduce allocation in gRPC server convention #7581

📔 Documentation

• Clarify time series produced by LongTaskTimer when using Prometheus #6507
• Document metrics that need to close the MeterBinder #4624
• Multigauge Documentation lacks overwrite=true #4403

❤️ Contributors

Thank you to all the contributors who worked on this release:

@izeye, @jewoodev, @codingkiddo, @schiemon, @blaspat

⭐ New Features

• Add meter for ForkJoinPool#getDelayedTaskCount #6381
• Add support for JDK 26's MemoryPoolMXBean.getTotalGcCpuTime() #7245
• Clear the state of the ObservationValidator #7337
• Improve exemplars sizing and add exemplarsSize config #7324
• Log warning when a registry is added to composite after meter registration #6908
• Treat OkHttp Request as non-nullable #7388
• Validate Observation.Scope closing when using TestObservationRegistry #6329

🐞 Bug Fixes

• Invalid reflection hint in micrometer-core for native GraalVM 25 build #7316
• ObservationGrpcClientInterceptor throws NPE when NameResolver returns empty authority #7380
• ObservationValidator scope LIFO validation produces false positives for parallel observations #7288
• Wrong Nullability Information in OkHttpMetricsEventListener #7373

🔨 Dependency Upgrades

• Bump activemq-artemis from 2.52.0 to 2.53.0 #7317
• Bump biz.aQute.bnd:biz.aQute.bnd.gradle from 7.2.1 to 7.2.3 #7341
• Bump com.google.cloud:google-cloud-monitoring from 3.87.0 to 3.89.0 #7291
• Bump com.google.cloud:libraries-bom from 26.77.0 to 26.79.0 #7355
• Bump com.gradle.develocity from 4.3.2 to 4.4.0 #7343
• Bump com.gradleup.shadow from 9.3.2 to 9.4.1 #7354
• Bump com.netflix.nebula:gradle-info-plugin from 16.1.0 to 16.2.1 #7266
• Bump com.netflix.nebula:nebula-project-plugin from 13.0.1 to 13.1.0 #7282
• Bump com.netflix.nebula:nebula-publishing-plugin from 23.0.0 to 23.1.0 #7279
• Bump com.netflix.spectator:spectator-reg-atlas from 1.9.4 to 1.9.6 #7278
• Bump grpc from 1.79.0 to 1.80.0 #7304
• Bump io.prometheus:prometheus-metrics-bom from 1.5.0 to 1.5.1 #7318
• Bump org.jooq:jooq from 3.20.11 to 3.21.1 #7333
• Bump software.amazon.awssdk:cloudwatch from 2.42.10 to 2.42.9 #7361
• Bump spring6 from 6.2.16 to 6.2.17 #7292

❤️ Contributors

Thank you to all the contributors who worked on this release:

@Goooler, @Joowon-Seo, @belugabehr, @izeye, and @ribafish

🐞 Bug Fixes

• Invalid reflection hint in micrometer-core for native GraalVM 25 build #7316
• ObservationGrpcClientInterceptor throws NPE when NameResolver returns empty authority #7380
• Wrong Nullability Information in OkHttpMetricsEventListener #7373

🔨 Dependency Upgrades

• Bump com.netflix.spectator:spectator-reg-atlas from 1.9.4 to 1.9.6 #7393
• Bump spring6 from 6.2.16 to 6.2.17 #7294

❤️ Contributors

Thank you to all the contributors who worked on this release:

@Joowon-Seo, and @ribafish

🐞 Bug Fixes

• Invalid reflection hint in micrometer-core for native GraalVM 25 build #7316

🔨 Dependency Upgrades

• Bump org.apache.maven:maven-resolver-provider from 3.9.13 to 3.9.14 #7280
• Bump spring6 from 6.2.16 to 6.2.17 #7294

❤️ Contributors

@Joowon-Seo and @ribafish
Thank you to all the contributors who worked on this release:

See also the 1.17 migration guide.

Deprecations

• Deprecate DynatraceConfig#group #7181
• Un-deprecate DynatraceConfig#apiToken #7180
• Deprecate unused Observation.Scope-related methods #7255

⭐ New Features

• Make OtlpMetricsSender.Request#toString human-readable #7264
• OTLP exemplar support #3795
• Support meters with the same name but different set of tag keys in PrometheusMeterRegistry #877

Dependency upgrades

• Bump io.opentelemetry.proto:opentelemetry-proto from 1.9.0-alpha to 1.10.0-alpha #7265

❤️ Contributors

Thank you to all the contributors who worked on this release:

@izeye