otelcol.processor.cumulativetodelta
Public preview

otelcol.processor.cumulativetodelta

Public preview: This is a public preview component. Public preview components are subject to breaking changes, and may be replaced with equivalent functionality that cover the same use case. The stability.level flag must be set to public-preview or below to use the component.

otelcol.processor.cumulativetodelta accepts metrics from other otelcol components and converts metrics with the cumulative temporality to delta.

Note

otelcol.processor.cumulativetodelta is a wrapper over the upstream OpenTelemetry Collector cumulativetodelta processor. Bug reports or feature requests will be redirected to the upstream repository, if necessary.

You can specify multiple otelcol.processor.cumulativetodelta components by giving them different labels.

Usage

alloy
otelcol.processor.cumulativetodelta "<LABEL>" {
  output {
    metrics = [...]
  }
}

Arguments

You can use the following arguments with otelcol.processor.cumulativetodelta:

NameTypeDescriptionDefaultRequired
initial_valuestringHandling of the first observed point for a given metric identity."auto"no
max_stalenessdurationThe total time a state entry will live past the time it was last seen."0"no

otelcol.processor.cumulativetodelta tracks incoming metric streams. Sum and exponential histogram metrics with delta temporality are tracked and converted into cumulative temporality.

If a new sample hasn’t been received since the duration specified by max_staleness, tracked streams are considered stale and dropped. When set to "0", the state is retained indefinitely.

The initial_value sets the handling of the first observed point for a given metric identity. When the collector (re)starts, there’s no record of how much of a given cumulative counter has already been converted to delta values.

  • "auto" (default): Send the observed value if the start time is set AND the start time happens after the component started AND the start time is different from the timestamp. This is suitable for gateway deployments. This heuristic is like drop, but it keeps values for newly started counters which could not have had previous observed values.
  • "keep": Send the observed value as the delta value. This is suitable for when the incoming metrics haven’t been observed before. For example, when you are running the collector as a sidecar, the collector lifecycle is tied to the metric source.
  • "drop": Keep the observed value but don’t send it. This is suitable for gateway deployments. It guarantees that all delta counts it produces haven’t been observed before, but drops the values between the first two observations.

Blocks

You can use the following blocks with otelcol.processor.cumulativetodelta:

BlockDescriptionRequired
outputConfigures where to send received telemetry data.yes
debug_metricsConfigures the metrics that this component generates to monitor its state.no
excludeConfigures which metrics to not convert to delta.no
includeConfigures which metrics to convert to delta.no

If metric matches both include and exclude, exclude takes preference. If neither include nor exclude are supplied, no filtering is applied.

output

Required

The output block configures a set of components to forward resulting telemetry data to.

The following arguments are supported:

NameTypeDescriptionDefaultRequired
logslist(otelcol.Consumer)List of consumers to send logs to.[]no
metricslist(otelcol.Consumer)List of consumers to send metrics to.[]no
traceslist(otelcol.Consumer)List of consumers to send traces to.[]no

You must specify the output block, but all its arguments are optional. By default, telemetry data is dropped. Configure the metrics, logs, and traces arguments accordingly to send telemetry data to other components.

include

The include block configures which metrics to convert to delta.

The following attributes are supported:

NameTypeDescriptionDefaultRequired
metricslist(string)Names or patterns to convert to delta.no
match_typestringMatch type to use, strict or regexp.no
metric_typeslist(string)Metric types to convert to delta.no

If one of metrics or match_type is supplied, the other must be supplied too.

Valid values for metric_types are sum and histogram.

exclude

The exclude block configures which metrics not to convert to delta. exclude takes precedence over include

The following attributes are supported:

NameTypeDescriptionDefaultRequired
metricslist(string)Names or patterns to exclude when converting to delta.no
match_typestringMatch type to use, strict or regexp.no
metric_typeslist(string)Metric types to exclude when converting to delta.no

If one of metrics or match_type is supplied, the other must be supplied too.

Valid values for metric_types are sum and histogram.

debug_metrics

The debug_metrics block configures the metrics that this component generates to monitor its state.

The following arguments are supported:

NameTypeDescriptionDefaultRequired
disable_high_cardinality_metricsbooleanWhether to disable certain high cardinality metrics.trueno
levelstringControls the level of detail for metrics emitted by the wrapped collector."detailed"no

disable_high_cardinality_metrics is the Grafana Alloy equivalent to the telemetry.disableHighCardinalityMetrics feature gate in the OpenTelemetry Collector. It removes attributes that could cause high cardinality metrics. For example, attributes with IP addresses and port numbers in metrics about HTTP and gRPC connections are removed.

Note

If configured, disable_high_cardinality_metrics only applies to otelcol.exporter.* and otelcol.receiver.* components.

level is the Alloy equivalent to the telemetry.metrics.level feature gate in the OpenTelemetry Collector. Possible values are "none", "basic", "normal" and "detailed".

Exported fields

The following fields are exported and can be referenced by other components:

NameTypeDescription
inputotelcol.ConsumerA value that other components can use to send telemetry data to.

input accepts otelcol.Consumer data for metrics.

Component health

otelcol.processor.cumulativetodelta is only reported as unhealthy if given an invalid configuration.

Debug information

otelcol.processor.cumulativetodelta doesn’t expose any component-specific debug information.

Example

This example converts cumulative temporality metrics to delta before sending it to otelcol.exporter.otlp for further processing.

alloy
otelcol.processor.cumulativetodelta "default" {
  output {
    metrics = [otelcol.exporter.otlp.production.input]
  }
}

otelcol.exporter.otlp "production" {
  client {
    endpoint = sys.env("OTLP_SERVER_ENDPOINT")
  }
}

Compatible components

otelcol.processor.cumulativetodelta can accept arguments from the following components:

otelcol.processor.cumulativetodelta has exports that can be consumed by the following components:

Note

Connecting some components may not be sensible or components may require further configuration to make the connection work correctly. Refer to the linked documentation for more details.