[collector] Memory limiter processor cannot be disabled

[rogercoll]

The collector's Helm Chart allows disabling any configuration's component by setting it to null, for example:

  receivers:
    jaeger: null
    prometheus: null
    zipkin: null

In addition, custom pipelines that don't use these components must also be provided. This is particularly useful when using the Helm Chart with a collector distribution that does not embed some of the default chart components.

The same concept cannot be applied to the memory_limiter processor because it is always added by the chart when not defined by the user, see template:

{{- define "opentelemetry-collector.baseConfig" -}}
{{- $processorsConfig := get .Values.config "processors" }}
{{- if not $processorsConfig.memory_limiter }}
{{-   $_ := set $processorsConfig "memory_limiter" (include "opentelemetry-collector.memoryLimiter" . | fromYaml) }}
{{- end }}

Is the memory_limiter component a requirement for this chart? What do you think of adding a new value to parametrize it like the .Values.useGOMEMLIMIT but for the memory_limiter? (e.g .Values.useK8SMEMLIMIT)

[TylerHelmuth]

Although it is a best practice, the chart shouldn't be requiring it since the collector can run fine without it (unlike who we must have the health_check extension).

I'd be ok with updating the template to not add it back if it is not present. I don't think we need any other fields to control it. Would you like to submit that fix?

[rogercoll]

I'd be ok with updating the template to not add it back if it is not present. I don't think we need any other fields to control it. Would you like to submit that fix?

👍 Definitely, preparing the fix