Description

We currently record a few metrics related to the APM Server's event processing and golang memory allocations. We're still missing some more metrics to help us collect data points that are useful as it comes to sizing APM Server and understanding its memory usage.

We should aim to record (ideally in a histogram so we can see distributions):

• RSS memory consumption
• Goroutines
• Available indexers

GC metrics (Go docs):

• GC cycles
• Heap information