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OpenTelemetry

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OpenTelemetry .NET SDK

Last release 17 days ago
21 Sep 2026
Release timing varies
gaps range from 8 days to 5 months
Nearly every release is documented
notes for 26 of 28 stable releases
4 versions withdrawn
withdrawn after publishing
127 years old
50 releases · first in 1900

Release timeline

50 releases since 1900

1900190219041906

Releases

1.19.121 Sept 2026
For highlights and announcements see: https://github.com/open-telemetry/opentelemetry-dotnet/blob/core-1.19.1/RELEASENOTES.md.
For highlights and announcements see: https://github.com/open-telemetry/opentelemetry-dotnet/blob/core-1.19.1/RELEASENOTES.md.

For detailed changes see: https://github.com/open-telemetry/opentelemetry-dotnet/blob/core-1.19.1/src/OpenTelemetry/CHANGELOG.md.
Additional notes2 sources agree
Release details: 1.19.1

Fixed NotSupportedException thrown when building a TracerProvider or MeterProvider with a large number of wildcard source/meter patterns on net8.0, and a related OutOfMemoryException that could occur when many such providers were built over the lifetime of a process.
Open source →
Additional notes
Released 2026-Sep-21

Open source →

From the same repository

open-telemetry/opentelemetry-dotnet

For highlights and announcements see: https://github.com/open-telemetry/opentelemetry-dotnet/blob/core-1.19.0/RELEASENOTES.md.

    For detailed changes see: https://github.com/open-telemetry/opentelemetry-dotnet/blob/core-1.19.0/src/OpenTelemetry/CHANGELOG.md.

Additional notes2 sources agree

Release details: 1.19.0

Added Schema URL to internally created Resource instances.
Added AlwaysRecordSampler.
Added an AddOpenTelemetry extension method for IHostApplicationBuilder. It registers the OpenTelemetry SDK services and additionally seeds service.name from IHostEnvironment.ApplicationName and deployment.environment.name from IHostEnvironment.EnvironmentName as low-priority resource defaults. It also registers the host's live configuration into DI so that extensions receiving only IServiceCollection can contribute configuration sources during setup.
Extended key/value list attribute handling to cover additional dictionary shapes (IEnumerable<KeyValuePair<string, string?>> and IDictionary). These attributes will be serialized as JSON objects or kvlist, as appropriate.
If an exception is thrown when serializing an attribute, the attribute will now be dropped.
Disable HttpClientFactory integration on browser WebAssembly (e.g. Blazor) environments to avoid stalled export requests when async HTTP handlers are used.
Fixed CA certificate loading (e.g. using OTEL_EXPORTER_OTLP_CERTIFICATE) for PEM-encoded certificates that only contain a public key.
Fixed CircularBufferBuckets so the first delta histogram insertion after a reset does not result in an unnecessary scale reduction.
Fixed lazy logger provider builds after a failure from reusing partially initialized provider state.
Fixed parsing of an inbound tracestate header whose member value trimmed to an empty value that previously threw an IndexOutOfRangeException internally and could silently truncate the tracestate.
Prevented oversized metric metadata from being cached when it cannot fit within the configured request size.
Reduced allocations when formatting self-diagnostics events with up to three parameters.
Improved wildcard source/meter name matching to avoid excessive matching time at runtime.
Reduced allocations when creating log record attributes from an array.
Reduced allocations when setting baggage through the params overload.
Reduced allocations when constructing SpanAttributes from an array.

Open source →

Additional notes

Released 2026-Sep-18

Open source →

1.18.021 Aug 2026

For highlights and announcements see: https://github.com/open-telemetry/opentelemetry-dotnet/blob/core-1.18.0/RELEASENOTES.md.

    For detailed changes see: https://github.com/open-telemetry/opentelemetry-dotnet/blob/core-1.18.0/src/OpenTelemetry/CHANGELOG.md.

Additional notes2 sources agree

Release details: 1.18.0

Breaking change: The maximum size of a single OTLP export request is now 64 MiB by default instead of 128 MiB to conform with the OpenTelemetry specification. Raise the value of the new OtlpExporterOptions.MaxRequestSizeBytes property to increase the capacity.
Added OtlpExporterOptions.MaxRequestSizeBytes to configure the maximum OTLP request size limit, as required by the OpenTelemetry specification. The default is the recommended 64 MiB. A batch whose serialized payload exceeds the limit is not sent and is dropped in its entirety. The maximum supported value is 256 MiB.
Added OtlpExporterOptions.MaxResponseSizeBytes to configure the maximum size of a response the exporter will accept, as required by the OpenTelemetry specification. The default is the recommended 4 MiB. A response exceeding the limit is discarded and treated as a non-retryable failure.
Added the otel.sdk.processor.log.processed and otel.sdk.processor.span.processed SDK self-observability metrics.
Added support for serializing attribute values that are key/value lists in the OTLP, console and Zipkin exporters.
The OTLP exporter will now export the logger version, if it was specified.
Add new ITelemetryHostInitializer interface for applications that do not support hosted services, such as Blazor, to use to manually initialize the OpenTelemetry SDK as part of application startup.
BatchActivityExportProcessor and SimpleActivityExportProcessor no longer forward spans to the exporter once Shutdown has been called, and BatchActivityExportProcessor.Shutdown now waits for in-flight OnEnd calls to finish enqueueing before flushing.
Fixed self-diagnostics log lines being silently dropped when an event message was too long to fit in the internal buffer. Such content is now truncated.
Fixed activity creation throwing when multiple tracer providers returned a sampler attribute with the same key.
Fixed logger, meter and tracer providers leaking background threads if an exception is thrown by their constructor after resource creation.
Avoid formatting exceptions and creating exception attributes when RecordException is called on a span that is not recorded.
Fixed UseOtlpExporter to respect options configured with services.Configure<OtlpExporterOptions>(...).
Clamped the server-supplied OTLP/gRPC retry delay (RetryInfo.retry_delay) to a minimum value of 100 milliseconds.
Fixed serialization failures leaving failed trace, metric, and log batches in the serializer's per-thread state.
Fixed the persistent-storage retry thread terminating permanently on an unexpected exception.
Fixed the OTLP exporter from retrying certain non-transient HTTP failures.
Improved OTLP log attribute serialization performance by avoiding unnecessary boxing.
Improved OTLP histogram serialization performance by avoiding a redundant scan of explicit bucket bounds.
Fixed persistent storage allowing a blob write to exceed the configured maximum storage size.
Improved OTLP/gRPC response status handling performance by avoiding unnecessary header enumeration on .NET 8+.
Fixed the Zipkin exporter to read responses with HttpCompletionOption.ResponseHeadersRead for the .NET Framework and .NET Standard targets.
Fixed inefficient parsing of the Jaeger uber-trace-id header when targeting net462 or netstandard2.0.

Open source →

Additional notes

Released 2026-Aug-21

Open source →

1.17.016 Jul 2026

For highlights and announcements see: https://github.com/open-telemetry/opentelemetry-dotnet/blob/core-1.17.0/RELEASENOTES.md.

    For detailed changes see: https://github.com/open-telemetry/opentelemetry-dotnet/blob/core-1.17.0/src/OpenTelemetry/CHANGELOG.md.

Additional notes2 sources agree

Release details: 1.17.0

Added support for a Schema URL on Resource instances.
The Resource Schema URL is now printed alongside the resource attributes when using the Console and OTLP exporters.
Added ExcludedTagKeys property to MetricStreamConfiguration to support excluding specific tag keys from metric streams.
Updated tracestate key validation to comply with the W3C Trace Context Level 2 grammar.
The SDK now depends on Microsoft.Extensions.Configuration.EnvironmentVariables instead of using a vendored implementation.
All libraries are now marked as trim and AOT compatible.
Fixed a metric storage leak that occurred when meters and instruments were repeatedly created and disposed.
Fixed TraceContextPropagator to normalize empty tracestate header values to null when extracting trace context.
Fixed OtlpLogExporter so OtlpExporterOptions.ExportProcessorType and OtlpExporterOptions.BatchExportProcessorOptions are respected when LogRecordExportProcessorOptions are not configured.
Fixed the OTLP exporter dropping retryable data instead of saving it to disk when persistent storage retry is enabled and an export exceeds the configured timeout.
Fixed the OTLP/HTTP exporter silently dropping data when an export timed out.
Fixed the OTLP/gRPC exporter logging incorrectly when an export timed out.
Performance and memory improvements for the OTLP exporter when exporting logs and metrics.

Open source →

Additional notes

Released 2026-Jul-16

Open source →

1.16.010 Jun 2026

For highlights and announcements see: https://github.com/open-telemetry/opentelemetry-dotnet/blob/core-1.16.0/RELEASENOTES.md.

    For detailed changes see: https://github.com/open-telemetry/opentelemetry-dotnet/blob/core-1.16.0/src/OpenTelemetry/CHANGELOG.md.

Additional notes2 sources agree

Release details: 1.16.0

Breaking Change Explicit histogram boundaries no longer allow more than 10 million values.
Fix BaggagePropagator to correctly follow Key and Value Encoding rules.
Add support for the W3C randomness flag.
Fixed TraceContextPropagator to deduplicate duplicate tracestate keys.
ObservedTimestamp will now be exported for logs in the console exporter.
Fixed NullReferenceException when exporting OTLP logs if the scope key is null.
Added opt-in support for gzip compression to the OTLP exporter.
Fixed OTLP disk retry data being stored incorrectly when using persistent storage retry.
Fixed OtlpLogExporter integration with IHttpClientFactory.
Do not enable the OTLP integration with IHttpClientFactory when mTLS is enabled.
Handle Retry-After response headers that specify a date instead of a delay.
observed_time_unix_nano will no longer always be identical to time_unix_nano when using the logs bridge API.
Stop validating View-provided metric stream Name against the instrument name syntax.
Fix incorrect validation of OTEL_BSP_* and OTEL_BLRP_* environment variables.
Fix observable instrument callbacks running once per reader instead of once per collection cycle.
Added exception safety for user-supplied ExemplarReservoir implementations.
Fixed a circular reference which could cause a LoggerProvider to fail to resolve when one of its dependencies depends on ILogger or ILoggerFactory.

Open source →

Additional notes

Released 2026-Jun-10

Open source →

1.15.321 Apr 2026

For highlights and announcements see: https://github.com/open-telemetry/opentelemetry-dotnet/blob/core-1.15.3/RELEASENOTES.md.

    For detailed changes see: https://github.com/open-telemetry/opentelemetry-dotnet/blob/core-1.15.3/src/OpenTelemetry/CHANGELOG.md.

Additional notes2 sources agree

Release details: 1.15.3

Breaking change: Fixed tracestate parsing to reject keys that do not begin with a lowercase letter, including keys beginning with digits, to align with the W3C Trace Context specification.
Breaking change: Fixed an insecure disk retry default for OTLP export. Disk retry now requires OTEL_DOTNET_EXPERIMENTAL_OTLP_DISK_RETRY_DIRECTORY_PATH when OTEL_DOTNET_EXPERIMENTAL_OTLP_RETRY=disk is configured.
Improve efficiency of parsing of baggage and B3 propagation headers.
OtlpLogExporter now uses IHttpClientFactory on .NET 8+.
Fixed an issue in OTLP/gRPC retry handling when parsing gRPC statuses.
Fixed OTEL_SPAN_ATTRIBUTE_VALUE_LENGTH_LIMIT not being applied.
Fixed baggage and trace headers not respecting the maximum length in some cases.
Fixed BaggagePropagator to trim optional whitespace (OWS) around = separators when parsing the baggage header.
Fixed BaggagePropagator to strip baggage properties from values when parsing the baggage header.
Fixed OTLP persistent storage clean-up handling for malformed filenames.
Fixed resource leak in batch and periodic exporting task workers for Blazor/WASM.
Fixed LogRecord.LogLevel to preserve LogLevel.None.
Fixed OTEL_TRACES_SAMPLER_ARG handling for out-of-range values.
Fixed an issue with OTLP disk retry storage where metrics and logs used the traces storage directory.
Fixed full OTLP endpoint being logged by internal diagnostics.
Improve efficiency of parsing of baggage, B3 and Jaeger propagation headers.
Hardened Zipkin exporter memory usage for endpoint caching and array tag serialization.

Open source →

Additional notes

Released 2026-Apr-21

Fix resource leak in batch and periodic exporting task workers for Blazor/WASM. (#7069)
Fixed LogRecord.LogLevel to preserve LogLevel.None and handle unspecified or out-of-range severities without returning invalid enum values. (#7092)
Fixed OTEL_TRACES_SAMPLER_ARG handling to treat out-of-range, NaN, and infinite values as invalid and fall back to the default ratio when using traceidratio and parentbased_traceidratio samplers. (#7103)

Open source →

1.15.28 Apr 2026

For highlights and announcements see: https://github.com/open-telemetry/opentelemetry-dotnet/blob/core-1.15.2/RELEASENOTES.md.

    For detailed changes see: https://github.com/open-telemetry/opentelemetry-dotnet/blob/core-1.15.2/src/OpenTelemetry/CHANGELOG.md.

Additional notes2 sources agree

Release details: 1.15.2

Limit how much of the response body is read by the OTLP exporter when export fails and error logging is enabled.
Added Task-based worker support for BatchExportProcessor and PeriodicExportingMetricReader to enable the OpenTelemetry SDK to work in single-threaded WebAssembly environments such as Blazor and Uno Platform.

Open source →

Additional notes

Released 2026-Apr-08

Added Task-based worker support for BatchExportProcessor and PeriodicExportingMetricReader to enable OpenTelemetry to work in single-threaded WebAssembly environments such as Blazor and Uno Platform. The implementation automatically detects the WebAssembly runtime and switches to Task-based workers accordingly; the Thread-based approach remains the default on all other platforms. (#6379)

Open source →

1.15.127 Mar 2026

For highlights and announcements see: https://github.com/open-telemetry/opentelemetry-dotnet/blob/core-1.15.1/RELEASENOTES.md.

    For detailed changes see: https://github.com/open-telemetry/opentelemetry-dotnet/blob/core-1.15.1/src/OpenTelemetry/CHANGELOG.md.

Additional notes2 sources agree

Release details: 1.15.1

Breaking change: The Baggage API now disallows empty baggage names and treats baggage names and values as case sensitive, aligning with the latest Baggage API specification.
Various bug fixes across OpenTelemetry.Api and OpenTelemetry SDK, including fixes for thread-safety, sampler edge cases, metrics precision, and observable instrument lifecycle handling.

Open source →

Additional notes

Released 2026-Mar-27

Fixed Tracer.StartSpan() leaving the new span as Activity.Current when the previous activity was stopped by another thread during span creation. (#6257)
Fixed OverflowException in TraceIdRatioBasedSampler when trace ID bytes produced long.MinValue. (#6928)
Fixed precision issues when using Histogram<float> with custom HistogramBucketBoundaries. (#6866)
Fixed a thread-safety issue in LogRecordSharedPool.Rent(). (#6833)
Fixed observable instruments (ObservableCounter, ObservableUpDownCounter, ObservableGauge) continuing to export stale data points after a callback stops reporting a series. (#5950)

Open source →

1.15.021 Jan 2026

For highlights and announcements see: https://github.com/open-telemetry/opentelemetry-dotnet/blob/core-1.15.0/RELEASENOTES.md.

    For detailed changes see: https://github.com/open-telemetry/opentelemetry-dotnet/blob/core-1.15.0/src/OpenTelemetry/CHANGELOG.md.

Additional notes2 sources agree

Release details: 1.15.0

Added support for ActivitySource.TelemetrySchemaUrl and Meter.TelemetrySchemaUrl properties across exporters.
Improved performance and reduced memory consumption for metrics histograms.
Added mTLS configuration support for the OTLP exporter (client cert/key and CA certificate options).
OpenTelemetry.Exporter.Zipkin is deprecated and will stop receiving updates in December 2026. Zipkin already supports OTLP ingestion. Migrate to OpenTelemetry.Exporter.OpenTelemetryProtocol as stated in the Deprecating Zipkin Exporter blog post.

Open source →

Additional notes

Released 2026-Jan-21

Added support for the OTEL_SDK_DISABLED environment variable in TracerProvider, MeterProvider, and LoggerProvider. When OTEL_SDK_DISABLED=true, the SDK returns no-op implementations for all telemetry signals. The OTEL_SDK_DISABLED environment variable is only evaluated upon application startup, later changes have no effect. (#6568)
Added LowMemory temporality as an option in the OTLP metrics exporter. (#6648)
Added support for Meter.TelemetrySchemaUrl property. (#6714)
Improve performance and reduce memory consumption for metrics histograms. (#6715)
Decode value in OTEL_RESOURCE_ATTRIBUTES environment variable. (#6737)

Open source →

1.14.012 Nov 2025

For highlights and announcements see: https://github.com/open-telemetry/opentelemetry-dotnet/blob/core-1.14.0/RELEASENOTES.md.

    For detailed changes see: https://github.com/open-telemetry/opentelemetry-dotnet/blob/core-1.14.0/src/OpenTelemetry/CHANGELOG.md.

Additional notes2 sources agree

Release details: 1.14.0

Add support for .NET 10.0.
Breaking Change When targeting net8.0, the package now depends on version 8.0.0 of the Microsoft.Extensions.DependencyInjection.Abstractions, Microsoft.Extensions.Diagnostics.Abstractions, Microsoft.Extensions.Hosting.Abstractions and Microsoft.Extensions.Logging.Configuration NuGet packages.
Update System.Diagnostics.DiagnosticSource dependency to 10.0.0 for all target frameworks.
Update Microsoft.Extensions.* dependencies to 10.0.0 for .NET Framework and .NET Standard.
Breaking Change NuGet packages now use the Sigstore bundle format (.sigstore.json) for digital signatures instead of separate signature (.sig) and certificate (.pem) files. This requires cosign 3.0 or later for verification. See the Digital signing section for updated verification instructions.

Open source →

Additional notes

Released 2025-Nov-12

Breaking Change NuGet packages now use the Sigstore bundle format (.sigstore.json) for digital signatures instead of separate signature (.sig) and certificate (.pem) files. This requires cosign 3.0 or later for verification. See the Digital signing section for updated verification instructions. (#6623)
Update to stable versions for .NET 10.0 NuGet packages. (#6667)
Update Microsoft.Extensions.* dependencies to 10.0.0 for .NET Framework and .NET Standard. (#6667)

Open source →

1.13.19 Oct 2025

For highlights and announcements see: https://github.com/open-telemetry/opentelemetry-dotnet/blob/core-1.13.1/RELEASENOTES.md.

    For detailed changes see: https://github.com/open-telemetry/opentelemetry-dotnet/blob/core-1.13.1/src/OpenTelemetry/CHANGELOG.md.

Additional notes2 sources agree

Release details: 1.13.1

In version 1.13.0, the digital signature (.dll-keyless.sig) and certificate (.dll-keyless.pem) files were unintentionally omitted from the published NuGet packages.
This hotfix restores the Sigstore signing artifacts for all target frameworks (net462, netstandard2.0, netstandard2.1, net8.0, net9.0), ensuring the integrity of DLL verification using Sigstore cosign.

Open source →

Additional notes

Released 2025-Oct-09

Fixed an issue where the Base2 Exponential Bucket Histogram did not reset its scale to 20 after each collection cycle when using delta aggregation temporality. (#6557)

Open source →

1.13.01 Oct 2025

For highlights and announcements see: https://github.com/open-telemetry/opentelemetry-dotnet/blob/core-1.13.0/RELEASENOTES.md.

    For detailed changes see: https://github.com/open-telemetry/opentelemetry-dotnet/blob/core-1.13.0/src/OpenTelemetry/CHANGELOG.md.

Additional notes2 sources agree

Release details: 1.13.0

gRPC calls to export traces, logs, and metrics using OtlpExportProtocol.Grpc now set the TE=trailers HTTP request header to improve interoperability.
EventName is now exported by default as EventName instead of logrecord.event.name when specified through ILogger or the experimental log bridge API.

Open source →

Additional notes

Released 2025-Oct-01

Added a verification to ensure that a MetricReader can only be registered to a single MeterProvider, as required by the OpenTelemetry specification. (#6458)
Added FormatMessage configuration option to self-diagnostics feature. When set to true (default is false), log messages will be formatted by replacing placeholders with actual parameter values for improved readability.

Example OTEL_DIAGNOSTICS.json:
```
{
    "LogDirectory": ".",
    "FileSize": 32768,
    "LogLevel": "Warning",
    "FormatMessage": true
}
```
Fixed parsing of OTEL_TRACES_SAMPLER_ARG decimal values to always use . as the delimiter when using the traceidratio sampler, preventing locale-specific parsing issues. (#6444)

Open source →

1.12.030 Apr 2025Breaking2 sources agree

Breaking Change: OpenTelemetry.Exporter.OpenTelemetryProtocol now defaults to using OTLP/HTTP instead of OTLP/gRPC when targeting .NET Framework and .…

Release details: 1.12.0

Breaking Change: OpenTelemetry.Exporter.OpenTelemetryProtocol now defaults to using OTLP/HTTP instead of OTLP/gRPC when targeting .NET Framework and .NET Standard. This change may cause telemetry export to fail unless appropriate adjustments are made. Explicitly setting OTLP/gRPC may result in a NotSupportedException unless further configuration is applied. See #6209 for full details and mitigation guidance. #6229

Open source →

Additional notes

Released 2025-Apr-29

Open source →

1.11.01 Jan 1900withdrawn2 sources agree

OpenTelemetry.Exporter.OpenTelemetryProtocol no longer depends on the Google.Protobuf, Grpc, or Grpc.Net.Client packages. Serialization and transmissi

Release details: 1.11.0

OpenTelemetry.Exporter.OpenTelemetryProtocol no longer depends on the Google.Protobuf, Grpc, or Grpc.Net.Client packages. Serialization and transmission of outgoing data is now performed manually to improve the overall performance.

Open source →

Additional notes

Released 2025-Jan-15

Meter.Tags will now be considered when resolving the SDK metric to update when measurements are recorded. Meters with the same name and different tags will now lead to unique metrics. (#5982)
Fixed a bug in tracing where TraceState set by a custom Sampler is not applied when creating propagation-only spans. (#6058)

Open source →

1.10.01 Jan 1900withdrawn2 sources agree

Bumped the package versions of System.Diagnostic.DiagnosticSource and other Microsoft.Extensions.* packages to 9.0.0.

Release details: 1.10.0

Bumped the package versions of System.Diagnostic.DiagnosticSource and other Microsoft.Extensions.* packages to 9.0.0.
Added support for new APIs introduced in System.Diagnostics.DiagnosticSource 9.0.0:
- InstrumentAdvice<T>
  
  For details see: Explicit bucket histogram aggregation.
- Gauge<T>
- ActivitySource.Tags (supported in OtlpExporter & ConsoleExporter)
Experimental features promoted to stable:
- CardinalityLimit can now be managed for individual metrics via the View API. For details see: Changing cardinality limit for a Metric.
- The overflow attribute (otel.metric.overflow) behavior is now enabled by default. The OTEL_DOTNET_EXPERIMENTAL_METRICS_EMIT_OVERFLOW_ATTRIBUTE environment variable is no longer required. For details see: Cardinality Limits.
- The MetricPoint reclaim behavior is now enabled by default when Delta aggregation temporality is used. The OTEL_DOTNET_EXPERIMENTAL_METRICS_RECLAIM_UNUSED_METRIC_POINTS environment variable is no longer required. For details see: Cardinality Limits.
Added OpenTelemetrySdk.Create API for configuring OpenTelemetry .NET signals (logging, tracing, and metrics) via a single builder. This new API simplifies bootstrap and teardown, and supports cross-cutting extensions targeting IOpenTelemetryBuilder.
Removed out of support net6.0 target and added net9.0 target.

Open source →

Additional notes

Released 2024-Nov-12

Promoted the MetricPoint reclaim feature for Delta aggregation temporality from experimental to stable. (#5956)

Previous Behavior: The SDK maintained a fixed set of MetricPoints which were assigned on a first-come basis based on the tags. MetricPoint reclaim was an experimental feature users could opt-into setting the environment variable OTEL_DOTNET_EXPERIMENTAL_METRICS_RECLAIM_UNUSED_METRIC_POINTS=true.

New Behavior: MetricPoint reclaim is now enabled by default when Delta aggregation temporality is used without the need to set an environment variable. Unused MetricPoints will automatically be reclaimed and reused for future measurements. There is NO ability to revert to the old behavior.
Updated the Microsoft.Extensions.Logging.Configuration and Microsoft.Extensions.Diagnostics.Abstractions package versions to 9.0.0. (#5967)

Open source →

1.9.014 Jun 20242 sources agree

Exemplars are now part of the stable API! For details see: customizing exemplars collection.

Release details: 1.9.0

Exemplars are now part of the stable API! For details see: customizing exemplars collection.
WithLogging is now part of the stable API! Logging, Metrics, and Tracing can now all be configured using the With style and the builders finally have parity in their APIs.

Open source →

Additional notes

Released 2024-Jun-14

Open source →

1.8.03 Apr 20242 sources agree

TracerProvider sampler can now be configured via the OTEL_TRACES_SAMPLER & OTEL_TRACES_SAMPLER_ARG envvars.

Release details: 1.8.0

TracerProvider sampler can now be configured via the OTEL_TRACES_SAMPLER & OTEL_TRACES_SAMPLER_ARG envvars.
A new UseOtlpExporter cross-cutting extension has been added to register the OtlpExporter and enable all signals in a single call.
exception.type, exception.message, exception.stacktrace will now automatically be included by the OtlpLogExporter when logging exceptions. Previously an experimental environment variable had to be set.

Open source →

Additional notes

Released 2024-Apr-02

Open source →

1.7.09 Dec 20232 sources agree

Bumped the package versions of System.Diagnostic.DiagnosticSource and other Microsoft.Extensions.* packages to 8.0.0.

Release details: 1.7.0

Bumped the package versions of System.Diagnostic.DiagnosticSource and other Microsoft.Extensions.* packages to 8.0.0.
Added net8.0 targets to all the components.
OTLP Exporter
- Updated to use ILogger CategoryName as the instrumentation scope for logs.
- Added named options support for OTLP Log Exporter.
- Added support for instrumentation scope attributes in metrics.
- Added support under an experimental flag to emit log exception attributes.
- Added support under an experimental flag to emit log eventId and eventName. attributes.
Added support for the IMetricsBuilder API.
Added an experimental opt-in metrics feature to reclaim unused MetricPoints which enables a higher number of unique dimension combinations to be emitted. See reclaim unused metric points for more details.

Open source →

Additional notes

Released 2023-Dec-08

Open source →

1.6.06 Sept 2023

Increased the character limit of the Meter instrument name from 63 to 255.

Released 2023-Sep-05

Increased the character limit of the Meter instrument name from 63 to 255. (#4798)
Update default size for SimpleExemplarReservoir to 1. (#4803)
Update Metrics SDK to override the default histogram buckets for a set of well-known histogram metrics from ASP.NET Core and HttpClient runtime. These histogram metrics which have their Unit as s (second) will have their default histogram buckets as [ 0, 0.005, 0.01, 0.025, 0.05, 0.075, 0.1, 0.25, 0.5, 0.75, 1, 2.5, 5, 7.5, 10 ]. (#4820)

Open source →

1.5.126 Jun 2023Breaking

Fixed a breaking change causing LogRecord.State to be null where it was previously set to a valid value when OpenTelemetryLoggerOptions.ParseStateValu…

Released 2023-Jun-26

Fixed a breaking change causing LogRecord.State to be null where it was previously set to a valid value when OpenTelemetryLoggerOptions.ParseStateValues is false and states implement IReadOnlyList or IEnumerable of KeyValuePair<string, object>s. (#4609)
Breaking Change Removed the support for parsing TState types passed to the ILogger.Log<TState> API when ParseStateValues is true and TState does not implement either IReadOnlyList<KeyValuePair<string, object>> or IEnumerable<KeyValuePair<string, object>>. This feature was first introduced in the 1.5.0 stable release with #4334 and has been removed because it makes the OpenTelemetry .NET SDK incompatible with native AOT. (#4614)

Open source →

1.5.06 Jun 2023

Fixed a bug introduced by #4508 in 1.5.0-rc.1 which caused the "Build" extension to return null when performing chained/fluent calls.

Released 2023-Jun-05

Fixed a bug introduced by #4508 in 1.5.0-rc.1 which caused the "Build" extension to return null when performing chained/fluent calls. (#4529)
Marked Exemplars and related APIs internal as the spec for Exemplars is not stable yet. This would be added back in the 1.6.* prerelease versions right after 1.5.0 stable version is released. (#4533)

Open source →

1.2.0-rc513 Apr 2022pre-releaseBreaking

Removed the Temporality setting on MetricReader and replaced it with TemporalityPreference. This is a breaking change. TemporalityPreference is used t…

Released 2022-Apr-12

Removed the Temporality setting on MetricReader and replaced it with TemporalityPreference. This is a breaking change. TemporalityPreference is used to determine the AggregationTemporality used on a per-instrument kind basis. Currently, there are two preferences:
- Cumulative: Measurements from all instrument kinds are aggregated using AggregationTemporality.Cumulative.
- Delta: Measurements from Counter, ObservableCounter, and Histogram instruments are aggregated using AggregationTemporality.Delta. When UpDownCounters are supported with DiagnosticSource version 7.0 onwards, they will be aggregated using AggregationTemporality.Cumulative. (#3153)
Fix issue where ExplicitBucketHistogramConfiguration could be used to configure metric streams for instruments that are not histograms. Currently, it is not possible to change the aggregation of an instrument with views. This may be possible in the future. (#3126)
Conformed to the specification to ensure that each view that an instrument matches results in a new metric stream. With this change it is possible for views to introduce conflicting metric streams. Any conflicts encountered will result in a diagnostic log. (#3148)

Open source →

1.2.0-rc430 Mar 2022pre-release

The PeriodicExportingMetricReader now accepts an ExportIntervalMilliseconds of -1 indicating an infinite export interval period.

Released 2022-Mar-30

The PeriodicExportingMetricReader now accepts an ExportIntervalMilliseconds of -1 indicating an infinite export interval period. (#2982)
Fix bug where multiple views selecting a single instrument can result in duplicate updates to a single metric point. (#3006)
Added the PeriodicExportingMetricReaderOptions.ExportTimeoutMilliseconds option. (#3038)
Removed MetricReaderType. This enumeration was previously used when configuring a metric reader with an exporter to configure whether the export cycle would be periodic or manual (i.e., requiring a explicit call to flush metrics). This change affects the push-based metric exporters: OTLP, Console, and InMemory. For these exporters, a manual export cycle can now be achieved by setting PeriodicExportingMetricReaderOptions.ExportIntervalMilliseconds to -1. (#3038)
Marked members of the MetricPoint struct which do not mutate state as readonly (#3065)
[Bug fix] OpenTelemetryLoggerProvider is now unaffected by changes to OpenTelemetryLoggerOptions after the LoggerFactory is built. (#3055)

Open source →

1.2.0-rc35 Mar 2022pre-release

Instantiating multiple metric instruments with the same name and also identical in all other respects - same type, description, and unit - result in a

Released 2022-Mar-04

Instantiating multiple metric instruments with the same name and also identical in all other respects - same type, description, and unit - result in a single metric stream aggregating measurements from all the identical instruments. Instantiating multiple metric instruments with the same name but differ in some respect - different type, description, or unit - will result in a separate metric stream for each distinct instrument. (#2916)
The Meter property on OpenTelemetry.Metrics.Metric has been removed. It now has MeterName and MeterVersion properties. (#2916)
Added support for implementing custom ResourceDetector. (#2949 #2897)
Perf improvement for Histogram and HistogramSumCount by implementing lock-free updates. (#2951 #2961)

Open source →

1.2.0-rc23 Feb 2022pre-release

Make MetricPoint of MetricPointAccessor readonly.

Released 2022-Feb-02

Make MetricPoint of MetricPointAccessor readonly. (#2736)
Fail-fast when using AddView with guaranteed conflict. (#2751)
Swallow ObjectDisposedException from the BatchExportProcessor worker thread. (#2844)
Performance improvement: when emitting metrics, users are strongly advised to provide tags with same Key order, to achieve maximum performance. (#2805)

Open source →

1.2.0-rc130 Nov 2021pre-release

Prevent accessing activity Id before sampler runs in case of legacy activities.

Released 2021-Nov-29

Prevent accessing activity Id before sampler runs in case of legacy activities. (#2659)
Added ReadOnlyTagCollection and expose Tags on MetricPoint instead of Keys+Values (#2642)
Refactored MetricPoint and added public methods: GetBucketCounts, GetExplicitBounds, GetHistogramCount, and GetHistogramSum (#2657)
Remove MetricStreamConfiguration.Aggregation, as the feature to customize aggregation is not implemented yet. (#2660)
Removed the public property HistogramMeasurements and added a public method GetHistogramBuckets instead. Renamed the class HistogramMeasurements to HistogramBuckets and added an enumerator of type HistogramBucket for enumerating BucketCounts and ExplicitBounds. Removed GetBucketCounts and GetExplicitBounds methods from MetricPoint. (#2664)
Refactored temporality setting to align with the latest spec. (#2666)
Removed the public properties LongValue, DoubleValue, in favor of their counterpart public methods GetSumLong, GetSumDouble, GetGaugeLastValueLong, GetGaugeLastValueDouble. (#2667)
MetricType modified to reserve bits for future types. (#2693)

Open source →

1.2.0-alpha423 Sept 2021pre-release

BatchExportProcessor.OnShutdown will now log the count of dropped telemetry items.

Released 2021-Sep-23

BatchExportProcessor.OnShutdown will now log the count of dropped telemetry items. (#2331)
Changed CompositeProcessor<T>.OnForceFlush to meet with the spec requirement. Now the SDK will invoke ForceFlush on all registered processors, even if there is a timeout. (#2388)

Open source →

1.2.0-alpha314 Sept 2021pre-release

Metrics perf improvements, bug fixes. Replace MetricProcessor with MetricReader.

Released 2021-Sep-13

Metrics perf improvements, bug fixes. Replace MetricProcessor with MetricReader. (#2306)
Add BatchExportActivityProcessorOptions which supports field value overriding using OTEL_BSP_SCHEDULE_DELAY, OTEL_BSP_EXPORT_TIMEOUT, OTEL_BSP_MAX_QUEUE_SIZE, OTEL_BSP_MAX_EXPORT_BATCH_SIZE environmental variables as defined in the specification. (#2219)

Open source →

1.2.0-alpha225 Aug 2021pre-release

More Metrics features. All instrument types, push/pull exporters, Delta/Cumulative temporality supported.

Released 2021-Aug-24

More Metrics features. All instrument types, push/pull exporters, Delta/Cumulative temporality supported.
ResourceBuilder.CreateDefault has detectors for OTEL_RESOURCE_ATTRIBUTES, OTEL_SERVICE_NAME environment variables so that explicit AddEnvironmentVariableDetector call is not needed. (#2247)
ResourceBuilder.AddEnvironmentVariableDetector handles OTEL_SERVICE_NAME environmental variable. (#2209)
Removes upper constraint for Microsoft.Extensions.Logging dependencies. (#2179)
OpenTelemetryLogger modified to not throw, when the formatter supplied in ILogger.Log call is null. (#2200)

Open source →

1.1.0-beta312 May 2021pre-release

AddLegacySource() moved out of TracerProviderBuilderExtensions and into public API

Released 2021-May-11

AddLegacySource() moved out of TracerProviderBuilderExtensions and into public API (#2019)
Fixed an issue causing inconsistent log scopes when using BatchLogRecordExportProcessor. To make parsing scopes easier the LogRecord.ForEachScope signature has been changed to receive instances of LogRecordScope (a new type which implements IEnumerator<KeyValuePair<string, object>> for accessing scope items) (#2026)

Open source →

1.1.0-beta223 Apr 2021pre-release

Use AssemblyFileVersionAttribute instead of FileVersionInfo.GetVersionInfo to get the SDK version attribute to ensure that it works when the assembly

Released 2021-Apr-23

Use AssemblyFileVersionAttribute instead of FileVersionInfo.GetVersionInfo to get the SDK version attribute to ensure that it works when the assembly is not loaded directly from a file on disk (#1908)

Open source →

1.1.0-beta119 Mar 2021pre-release

Removed SuppressScope Increment/Decrement from DiagnosticSourceListeners. (1893)

Released 2021-Mar-19

Removed SuppressScope Increment/Decrement from DiagnosticSourceListeners. (1893)
Added TracerProviderBuilder.SetErrorStatusOnException which automatically sets the activity status to Error when exception happened. (#1858 #1875)
Added ForceFlush to TracerProvider. (#1837)
Added a TracerProviderBuilder extension method called AddLegacySource which is used by instrumentation libraries that use DiagnosticSource to get activities processed without ActivitySourceAdapter. #1836 #1860
Added new constructor with optional parameters to allow customization of ParentBasedSampler behavior. (#1727)
The application base directory is now tested after the current directory when searching for the self diagnostic configuration file. (#1865)
Resource Attributes now accept primitive arrays as values. (#1852)
Fixed #1846: ParentBasedSampler will no longer explicitly consider Activity links. (#1851)
Added IncludeScopes, IncludeFormattedMessage, & ParseStateValues on OpenTelemetryLoggerOptions. Added FormattedMessage, StateValues, & ForEachScope on LogRecord. (#1869 #1883)
Added SetResourceBuilder support to OpenTelemetryLoggerOptions. (#1913)
Added IDeferredTracerProviderBuilder and TracerProviderBuilderBase to support dependency injection through OpenTelemetry.Extensions.Hosting. (#1889)

Open source →

1.0.0-rc230 Jan 2021pre-release

The following extension methods on ResourceBuilder has been moved from the OpenTelemetry namespace to the OpenTelemetry.Resources namespace: AddEnviro

Released 2021-Jan-29

The following extension methods on ResourceBuilder has been moved from the OpenTelemetry namespace to the OpenTelemetry.Resources namespace: AddEnvironmentVariableDetector, AddAttributes, AddService, and AddTelemetrySdk. (#1576)
Metrics API/SDK support is in an experimental state and is not recommended for production use. All metric APIs have been marked with the Obsolete attribute. See #1501 for more information. (#1611)
Modified SimpleExportProcessor and BatchExportProcessor to abstract classes; Added SimpleActivityExportProcessor, SimpleLogRecordExportProcessor, BatchActivityExportProcessor, BatchLogRecordExportProcessor; Added the check for Activity.Recorded in SimpleActivityExportProcessor and BatchActivityExportProcessor (#1622)
Added check in ActivitySourceAdapter class for root activity if trace ID is overridden by calling SetParentId (#1355)
Resource Attributes now accept int, short, and float as values, converting them to supported data types (long for int/short, double for float). For invalid attributes we now throw an exception instead of logging an error. (#1720)
Merging "this" resource with an "other" resource now prioritizes the "other" resource's attributes in a conflict. We've rectified to follow a recent change to the spec. We previously prioritized "this" resource's tags. (#1728)
BatchExportProcessor will now flush any remaining spans left in a Batch after the export operation has completed. (#1726)
Fixed a bug to allow the Self Diagnostics log file to be opened simultaneously by another process in read-only mode for .NET Framework. (#1693)
Metrics removed as it is not part 1.0.0 release. See issue #1501 for details on Metric release plans.
Fix Resource attribute telemetry.sdk.version to have correct file version.
Metrics removed as it is not part 1.0.0 release. See issue #1501 for details on Metric release plans.

Open source →