[AutoInstrumentation] NodeJS histogram buckets should be configurable

[CCOLLOT]

Component(s)

auto-instrumentation

What happened?

Description

When injecting autoinstrumentation on nodejs apps, we use the default histogram buckets: [ 0, 5, 10, 25, 50, 75, 100, 250, 500, 750, 1000, 2500, 5000, 7500, 10000 ]

While it makes sense for values expressed in ms, it does not work with metrics such as http_server_duration_bucket expressed in seconds.

It seems other SDKs face(d) the same issue:

• .NET
• Go

I would expect to be able to configure the bucket list for metrics to adjust to the currently used unit, ideally through the Instrumentation CRD. As I understand it, we could, for example, pass a view to the created NodeSDK

While this is not an issue for span metrics or service-graph metrics (buckets can be configured downstream), it makes other metrics like http_server_duration_bucket unusable.

Kubernetes Version

1.30

Operator version

0.111.0

Collector version

0.111.0

Environment information

No response

Log output

No response

Additional context

No response

[swiatekm]

It looks like this was fixed in the instrumentation library itself for both dotnet and Go. Why aren't we doing the same thing for js?

[CCOLLOT]

It looks like this was fixed in the instrumentation library itself for both dotnet and Go. Why aren't we doing the same thing for js?

As far as I understand the Go SDK did not introduce a fix as maintainers refused to implement it.

Besides, even if the upstream project used another hardcoded set of buckets with the correct unit (seconds), an end-user might want to be able to change them.

I've seen comments from SDK maintainers arguing that one should just pass a view instead of modifying the default histogram buckets... But it cannot be done when using autoinstrumentation injection because the point is to avoid modifying the app's code :(.

[swiatekm]

I wonder if introducing a non-standard environment variable here is the way to go, or if we should add an attribute on the Instrumentation CR instead. I'd like to get opinions from the JS maintainers first, in any case.