Caution
Grafana Alloy is the new name for our distribution of the OTel collector. Grafana Agent has been deprecated and is in Long-Term Support (LTS) through October 31, 2025. Grafana Agent will reach an End-of-Life (EOL) on November 1, 2025. Read more about why we recommend migrating to Grafana Alloy.
Important: This documentation is about an older version. It's relevant only to the release noted, many of the features and functions have been updated or replaced. Please view the current version.
otelcol.processor.batch
otelcol.processor.batch
accepts telemetry data from other otelcol
components and places them into batches. Batching improves the compression of
data and reduces the number of outgoing network requests required to transmit
data. This processor supports both size and time based batching.
We strongly recommend that you configure the batch processor on every Agent that
uses OpenTelemetry (otelcol) Flow components. The batch processor should be
defined in the pipeline after the otelcol.processor.memory_limiter
as well
as any sampling processors. This is because batching should happen after any
data drops such as sampling.
NOTE:
otelcol.processor.batch
is a wrapper over the upstream OpenTelemetry Collectorbatch
processor. Bug reports or feature requests will be redirected to the upstream repository, if necessary.
Multiple otelcol.processor.batch
components can be specified by giving them
different labels.
Usage
otelcol.processor.batch "LABEL" {
output {
metrics = [...]
logs = [...]
traces = [...]
}
}
Arguments
otelcol.processor.batch
supports the following arguments:
Name | Type | Description | Default | Required |
---|---|---|---|---|
timeout | duration | How long to wait before flushing the batch. | "200ms" | no |
send_batch_size | number | Amount of data to buffer before flushing the batch. | 8192 | no |
send_batch_max_size | number | Upper limit of a batch size. | 0 | no |
metadata_keys | list(string) | Creates a different batcher for each key/value combination of metadata. | [] | no |
metadata_cardinality_limit | number | Limit of the unique metadata key/value combinations. | 1000 | no |
otelcol.processor.batch
accumulates data into a batch until one of the
following events happens:
The duration specified by
timeout
elapses since the time the last batch was sent.The number of spans, log lines, or metric samples processed exceeds the number specified by
send_batch_size
.
Use send_batch_max_size
to limit the amount of data contained in a single
batch. When set to 0
, batches can be any size.
For example, assume send_batch_size
is set to the default 8192
and there
are currently 8000 batched spans. If the batch processor receives 8000 more
spans at once, the total batch size would be 16,192 which would then be flushed
as a single batch. send_batch_max_size
constrains how big a batch can get.
When set to a non-zero value, send_batch_max_size
must be greater or equal to
send_batch_size
.
metadata_cardinality_limit
applies for the lifetime of the process.
Receivers should be configured with include_metadata = true
so that metadata
keys are available to the processor.
Each distinct combination of metadata triggers the allocation of a new
background task in the Agent that runs for the lifetime of the process, and each
background task holds one pending batch of up to send_batch_size
records. Batching
by metadata can therefore substantially increase the amount of memory dedicated to batching.
The maximum number of distinct combinations is limited to the configured metadata_cardinality_limit
,
which defaults to 1000 to limit memory impact.
Blocks
The following blocks are supported inside the definition of
otelcol.processor.batch
:
Hierarchy | Block | Description | Required |
---|---|---|---|
output | output | Configures where to send received telemetry data. | yes |
output block
The output
block configures a set of components to forward resulting
telemetry data to.
The following arguments are supported:
Name | Type | Description | Default | Required |
---|---|---|---|---|
metrics | list(otelcol.Consumer) | List of consumers to send metrics to. | [] | no |
logs | list(otelcol.Consumer) | List of consumers to send logs to. | [] | no |
traces | list(otelcol.Consumer) | List of consumers to send traces to. | [] | no |
The output
block must be specified, but all of its arguments are optional. By
default, telemetry data is dropped. To send telemetry data to other components,
configure the metrics
, logs
, and traces
arguments accordingly.
Exported fields
The following fields are exported and can be referenced by other components:
Name | Type | Description |
---|---|---|
input | otelcol.Consumer | A value that other components can use to send telemetry data to. |
input
accepts otelcol.Consumer
data for any telemetry signal (metrics,
logs, or traces).
Component health
otelcol.processor.batch
is only reported as unhealthy if given an invalid
configuration.
Debug information
otelcol.processor.batch
does not expose any component-specific debug
information.
Examples
Basic usage
This example batches telemetry data before sending it to otelcol.exporter.otlp for further processing:
otelcol.processor.batch "default" {
output {
metrics = [otelcol.exporter.otlp.production.input]
logs = [otelcol.exporter.otlp.production.input]
traces = [otelcol.exporter.otlp.production.input]
}
}
otelcol.exporter.otlp "production" {
client {
endpoint = env("OTLP_SERVER_ENDPOINT")
}
}
Batching based on metadata
Batching by metadata enables support for multi-tenant OpenTelemetry pipelines with batching over groups of data having the same authorization metadata.
otelcol.receiver.jaeger "default" {
protocols {
grpc {
include_metadata = true
}
thrift_http {}
thrift_binary {}
thrift_compact {}
}
output {
traces = [otelcol.processor.batch.default.input]
}
}
otelcol.processor.batch "default" {
// batch data by tenant id
metadata_keys = ["tenant_id"]
// limit to 10 batcher processes before raising errors
metadata_cardinality_limit = 123
output {
traces = [otelcol.exporter.otlp.production.input]
}
}
otelcol.exporter.otlp "production" {
client {
endpoint = env("OTLP_SERVER_ENDPOINT")
}
}