fuchsia.power.metrics

This library defines a protocol for test clients to communicate with the metrics recorder, specifying:

• Metrics type: e.g., temperature, CPU, GPU, network, power.
• Test duration.
• Sampling rate.
• Record processed statistics: minimum, maximum, and average values.
• Statistic processing interval (if applicable).

PROTOCOLS

Recorder

Defined in fuchsia.power.metrics/recorder.fidl

A protocol for managing on-demand metrics logging.

StartLogging

Initiates logging of specified metrics for the provided duration. Supports concurrent logging of different metrics. Logging may be terminated early with a call to StopLogging.

This call will fail if logging of the specified metric is already active. For this reason, a client may wish to precede a StartLogging call with a StopLogging call, after which the only reason for The logger to be active would be a conflict with another client.

• request client_id String format Id of the client. Client may choose any Id with a maximum byte size of 8 (e.g., "ffxTest").
• request metrics Type of the metrics to be polled and logged.
• request duration_ms Duration of logging in milliseconds. After this duration, polling and logging will cease.
• request output_samples_to_syslog Toggle for outputting raw data to syslog.
• request output_stats_to_syslog Toggle for outputting any available statistics to syslog.
• error a [fuchsia.metrics.test/MeticsLoggerError] value indicating why the request failed.

Request

Name	Type
client_id	ClientId
metrics	vector<Metric>
duration_ms	uint32
output_samples_to_syslog	bool
output_stats_to_syslog	bool

Response

Name	Type
payload	Recorder_StartLogging_Result

StartLoggingForever

Initiates logging of specified metrics. Supports concurrent logging of different metrics. Logging will only end upon a StopLogging call.

StartLogging should be preferred for usage in automated tests to ensure that logging terminates even if the test crashes.

• request client_id String format Id of the client. Client may choose any Id with a maximum byte size of 8 (e.g., "ffxTest").
• request metrics Type of the metrics to be polled and logged.
• request output_samples_to_syslog Toggle for outputting raw data to syslog.
• request output_stats_to_syslog Toggle for outputting any available statistics to syslog.
• error a [fuchsia.metrics.test/RecorderError] value indicating why the request failed.

Request

Name	Type
client_id	ClientId
metrics	vector<Metric>
output_samples_to_syslog	bool
output_stats_to_syslog	bool

Response

Name	Type
payload	Recorder_StartLoggingForever_Result

StopLogging

Terminates all active logging tasks with the given client_id. It is valid to call this method when logging is inactive.

• request client_id String format Id of the client.

• response status A bool value indicating if existing logging was stopped (true) or there'sno existing logging for the client.

Request

Name	Type
client_id	ClientId

Response

Name	Type
stopped	bool

STRUCTS

CpuLoad

Defined in fuchsia.power.metrics/recorder.fidl

CPU Load metric details.

Field	Type	Description	Default
interval_ms	uint32	Length of the polling interval in milliseconds. Must be smaller than duration_ms of the logging request. Must not be smaller than 500ms if output_samples_to_syslog is enabled in the logging request.	No default

GpuUsage

Defined in fuchsia.power.metrics/recorder.fidl

GPU Usage metric details.

Field	Type	Description	Default
interval_ms	uint32	Length of the polling interval in milliseconds. Must be smaller than duration_ms of the logging request. Must not be smaller than 500ms if output_samples_to_syslog is enabled in the logging request.	No default

NetworkActivity

Defined in fuchsia.power.metrics/recorder.fidl

Network Activity metric details.

Field	Type	Description	Default
interval_ms	uint32	Length of the polling interval in milliseconds. Must be smaller than duration_ms of the logging request. Must not be smaller than 500ms if output_samples_to_syslog is enabled in the logging request.	No default

Power

Defined in fuchsia.power.metrics/recorder.fidl

Power metric details.

Field	Type	Description	Default
sampling_interval_ms	uint32	Length of the sampling interval in milliseconds. Must not be smaller than 500ms if output_samples_to_syslog is enabled in the logging request. Must be smaller than duration_ms of the logging request.	No default
statistics_args	StatisticsArgs?	Boxed(optional) statistics arguments. If none, statistics is disabled.	No default

Recorder_StartLoggingForever_Response

Defined in fuchsia.power.metrics/recorder.fidl

<EMPTY>

Recorder_StartLogging_Response

Defined in fuchsia.power.metrics/recorder.fidl

<EMPTY>

StatisticsArgs

Defined in fuchsia.power.metrics/recorder.fidl

Field	Type	Description	Default
statistics_interval_ms	uint32	Length of the interval in milliseconds for summarizing statistics (e.g., min, max, avg). Must be equal to or larger than sampling_interval_ms in the metrics. Must be smaller than duration_ms of the logging request. Must not be smaller than 500ms if output_stats_to_syslog is enabled in the logging request.	No default

Temperature

Defined in fuchsia.power.metrics/recorder.fidl

Temperature metric details.

Field	Type	Description	Default
sampling_interval_ms	uint32	Length of the sampling interval in milliseconds. Must not be smaller than 500ms if output_samples_to_syslog is enabled in the logging request. Must be smaller than duration_ms of the logging request.	No default
statistics_args	StatisticsArgs?	Boxed(optional) statistics arguments. If none, statistics is disabled.	No default

ENUMS

RecorderError strict

Type: uint32

Defined in fuchsia.power.metrics/recorder.fidl

Errors associated with Recorder methods. If the request contains any of the following errors, it will fail without affecting the existing logging tasks.

Name	Value	Description
NO_DRIVERS	1	Indicates that no driver is found for requested metric logging.
INVALID_SAMPLING_INTERVAL	2	Indicates that an invalid sampling interval was provided.
ALREADY_LOGGING	3	Requests to start logging will fail if logging is already active for a given client.
DUPLICATED_METRIC	4	Indicates that the logging request contains duplicated metric type.
TOO_MANY_ACTIVE_CLIENTS	5	Indicates that the total number of active clients has reached the allowed maxium (defined by MAX_CONCURRENT_CLIENTS = 20 in the Recorder to keep memory use bounded).
INVALID_STATISTICS_INTERVAL	6	Indicates that statistics is enabled and an invalid statistics interval is provided.
INTERNAL	7	Indicates that the request failed due to an internal error.

UNIONS

Metric strict

Defined in fuchsia.power.metrics/recorder.fidl

Metric type requested in Recorder methods.

Ordinal	Variant	Type	Description
1	temperature	Temperature
2	cpu_load	CpuLoad
3	power	Power
4	gpu_usage	GpuUsage
5	network_activity	NetworkActivity

Recorder_StartLoggingForever_Result strict

Defined in fuchsia.power.metrics/recorder.fidl

Ordinal	Variant	Type	Description
1	response	Recorder_StartLoggingForever_Response
2	err	RecorderError

Recorder_StartLogging_Result strict

Defined in fuchsia.power.metrics/recorder.fidl

Ordinal	Variant	Type	Description
1	response	Recorder_StartLogging_Response
2	err	RecorderError

ALIASES

Name	Value	Description
ClientId	string[16]