CPUUsageGenerator generates CPU metric values.

DiskGenerator XXX.

MemoryGenerator collect memory usage `memory.{metric}`: using memory size[KiB] retrieved from /proc/meminfo metric = "total", "free", "buffers", "cached", "swap_cached", "swap_total", "swap_free" Metrics "used" is calculated by (total - available) when MemAvailable is available in /proc/meminfo and (total - free - buffers - cached) otherwise graph: stacks `memory.{metric}` */.