# Semantic conventions for physical host metrics **Status**: [Development][DocumentStatus] - [Physical host metrics `hw.host.*`](#physical-host-metrics-hwhost) - [Metric: `hw.host.ambient_temperature`](#metric-hwhostambient_temperature) - [Metric: `hw.host.energy`](#metric-hwhostenergy) - [Metric: `hw.host.heating_margin`](#metric-hwhostheating_margin) - [Metric: `hw.host.power`](#metric-hwhostpower) ## Physical host metrics `hw.host.*` Physical system as opposed to a virtual system or a container. Examples: physical server, switch or disk array. ### Metric: `hw.host.ambient_temperature` This metric is [recommended][MetricRecommended]. | Name | Instrument Type | Unit (UCUM) | Description | Stability | Entity Associations | | -------- | --------------- | ----------- | -------------- | --------- | ------ | | `hw.host.ambient_temperature` | Gauge | `Cel` | Ambient (external) temperature of the physical host. |  | | | Attribute | Type | Description | Examples | [Requirement Level](https://opentelemetry.io/docs/specs/semconv/general/attribute-requirement-level/) | Stability | |---|---|---|---|---|---| | [`hw.id`](/docs/registry/attributes/hardware.md) | string | An identifier for the hardware component, unique within the monitored host | `win32battery_battery_testsysa33_1` | `Required` |  | | [`hw.name`](/docs/registry/attributes/hardware.md) | string | An easily-recognizable name for the hardware component | `eth0` | `Recommended` |  | | [`hw.parent`](/docs/registry/attributes/hardware.md) | string | Unique identifier of the parent component (typically the `hw.id` attribute of the enclosure, or disk controller) | `dellStorage_perc_0` | `Recommended` |  | ### Metric: `hw.host.energy` This metric is [recommended][MetricRecommended]. | Name | Instrument Type | Unit (UCUM) | Description | Stability | Entity Associations | | -------- | --------------- | ----------- | -------------- | --------- | ------ | | `hw.host.energy` | Counter | `J` | Total energy consumed by the entire physical host, in joules. [1] |  | | **[1]:** The overall energy usage of a host MUST be reported using the specific `hw.host.energy` and `hw.host.power` metrics **only**, instead of the generic `hw.energy` and `hw.power` described in the previous section, to prevent summing up overlapping values. | Attribute | Type | Description | Examples | [Requirement Level](https://opentelemetry.io/docs/specs/semconv/general/attribute-requirement-level/) | Stability | |---|---|---|---|---|---| | [`hw.id`](/docs/registry/attributes/hardware.md) | string | An identifier for the hardware component, unique within the monitored host | `win32battery_battery_testsysa33_1` | `Required` |  | | [`hw.name`](/docs/registry/attributes/hardware.md) | string | An easily-recognizable name for the hardware component | `eth0` | `Recommended` |  | | [`hw.parent`](/docs/registry/attributes/hardware.md) | string | Unique identifier of the parent component (typically the `hw.id` attribute of the enclosure, or disk controller) | `dellStorage_perc_0` | `Recommended` |  | ### Metric: `hw.host.heating_margin` This metric is [recommended][MetricRecommended]. | Name | Instrument Type | Unit (UCUM) | Description | Stability | Entity Associations | | -------- | --------------- | ----------- | -------------- | --------- | ------ | | `hw.host.heating_margin` | Gauge | `Cel` | By how many degrees Celsius the temperature of the physical host can be increased, before reaching a warning threshold on one of the internal sensors. |  | | | Attribute | Type | Description | Examples | [Requirement Level](https://opentelemetry.io/docs/specs/semconv/general/attribute-requirement-level/) | Stability | |---|---|---|---|---|---| | [`hw.id`](/docs/registry/attributes/hardware.md) | string | An identifier for the hardware component, unique within the monitored host | `win32battery_battery_testsysa33_1` | `Required` |  | | [`hw.name`](/docs/registry/attributes/hardware.md) | string | An easily-recognizable name for the hardware component | `eth0` | `Recommended` |  | | [`hw.parent`](/docs/registry/attributes/hardware.md) | string | Unique identifier of the parent component (typically the `hw.id` attribute of the enclosure, or disk controller) | `dellStorage_perc_0` | `Recommended` |  | ### Metric: `hw.host.power` This metric is [recommended][MetricRecommended]. | Name | Instrument Type | Unit (UCUM) | Description | Stability | Entity Associations | | -------- | --------------- | ----------- | -------------- | --------- | ------ | | `hw.host.power` | Gauge | `W` | Instantaneous power consumed by the entire physical host in Watts (`hw.host.energy` is preferred). [1] |  | | **[1]:** The overall energy usage of a host MUST be reported using the specific `hw.host.energy` and `hw.host.power` metrics **only**, instead of the generic `hw.energy` and `hw.power` described in the previous section, to prevent summing up overlapping values. | Attribute | Type | Description | Examples | [Requirement Level](https://opentelemetry.io/docs/specs/semconv/general/attribute-requirement-level/) | Stability | |---|---|---|---|---|---| | [`hw.id`](/docs/registry/attributes/hardware.md) | string | An identifier for the hardware component, unique within the monitored host | `win32battery_battery_testsysa33_1` | `Required` |  | | [`hw.name`](/docs/registry/attributes/hardware.md) | string | An easily-recognizable name for the hardware component | `eth0` | `Recommended` |  | | [`hw.parent`](/docs/registry/attributes/hardware.md) | string | Unique identifier of the parent component (typically the `hw.id` attribute of the enclosure, or disk controller) | `dellStorage_perc_0` | `Recommended` |  | [DocumentStatus]: https://opentelemetry.io/docs/specs/otel/document-status [MetricRecommended]: /docs/general/metric-requirement-level.md#recommended