# OpenTelemetry Metrics

This is a list of metrics exported by the OpenTelemetry SDKs and auto-instrumentation libraries.

## General Metrics

The OpenTelemetry SDKs and auto-instrumentation libraries export the following general metrics:

| Metric Name | Description |
| --- | --- |
| `target_info` | Information about the target service, such as the service name, service namespace, and container name. |

Target information is exported as a set of labels, including:

| Label Name | Description | Example Value |
| --- | --- | --- |
| `os_description` | The operating system description. | `Linux 6.1.58+` |
| `os_type` | The operating system type. | `Linux` |
| `process_command_args` | The command arguments used to start the process. | `["/usr/lib/jvm/java-21-openjdk/bin/java","-jar","/app.jar"]` |
| `process_runtime_name` | The runtime name. | `OpenJDK Runtime Environment` |
| `process_runtime_version` | The runtime version. | `21.0.2+13-LTS` |
| `telemetry_sdk_language` | The telemetry SDK language. | `java` |
| `telemetry_sdk_version` | The telemetry SDK version. | `1.36.0` |

## HTTP Server Metrics

The OpenTelemetry SDKs and auto-instrumentation libraries export the following metrics for HTTP servers:

| Metric Name | Description |
| --- | --- |
| `http_server_request_duration_seconds_bucket` | Duration of HTTP server requests, in seconds (java and node.js) |

## HTTP Client Metrics

| Metric Name | Description |
| --- | --- |
| `http_client_request_duration_seconds_bucket` | Duration of HTTP client requests, in seconds (java) |
| `http_client_duration_milliseconds_bucket` | Duration of HTTP client requests, in milliseconds (node.js) |

## Database Client Connection Metrics

The OpenTelemetry SDKs and auto-instrumentation libraries export the following metrics for database clients:

| Metric Name | Description |
| --- | --- |
| `db_client_connections_create_time_milliseconds_bucket` | Duration of database client connection creation, in milliseconds. |
| `db_client_connections_create_time_milliseconds_count` | Count of database client connection creations, by duration. |
| `db_client_connections_create_time_milliseconds_sum` | Sum of database client connection creation durations, in milliseconds. |

## JVM Metrics

The OpenTelemetry SDKs and auto-instrumentation libraries export the following metrics for JVMs:

| Metric Name | Description |
| --- | --- |
| `jvm_buffer_count` | Count of JVM buffers. |
| `jvm_buffer_limit_bytes` | Limit of JVM buffer sizes, in bytes. |
| `jvm_buffer_usage_bytes` | Usage of JVM buffer sizes, in bytes. |

## Kafka Metrics

The OpenTelemetry SDKs and auto-instrumentation libraries export the following metrics for Kafka clients:

| Metric Name | Description |
| --- | --- |
| `kafka_producer_*` | Metrics for Kafka producers. |
| `kafka_consumer_*` | Metrics for Kafka consumers. |