# Structs
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", "active", "inactive", "swap_cached", "swap_total", "swap_free"
Metrics "used" is calculated here like (total - free - buffers - cached) for ease.