Go Runtime Metrics: include metric to replace `process.runtime.go.mem.heap_sys`

[obs-gh-mattcotter]

Area(s)

area:go

What's missing?

The deprecated runtime metrics contain the metric process.runtime.go.mem.heap_sys. This is useful for debugging, and I don't think there's currently a replacement.

I think this is analogous to /memory/classes/total:bytes, which is a component of go.memory.used, but there's no way to calculate /memory/classes/total:bytes from the result of the subtraction since neither metric is exposed individually.

Additional context: /memory/classes/total:bytes was in the Proposed initial metrics.

If my read of the docs is correct and these metrics are analogous, then I propose adding /memory/classes/total:bytes to the new runtime metrics as (e.g.) go.memory.total.

Describe the solution you'd like

New runtime metric added: go.memory.total

Tip

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