Every attribute represents the seconds the CPU has spent in the given mode. The attributes availability varies depending on the platform:
user: time spent by normal processes executing in user mode; on Linux this also includes guest time.system: time spent by processes executing in kernel mode.idle: time spent doing nothing.
Details
Platform-specific fields:
nice(UNIX): time spent by niced (prioritized) processes executing in user mode; on Linux this also includes guest_nice time.iowait(Linux): time spent waiting for I/O to complete. This is not accounted in idle time counter.irq(Linux): time spent for servicing hardware interrupts.softirq(Linux): time spent for servicing software interrupts.steal(Linux 2.6.11+): time spent by other operating systems running in a virtualized environment.guest(Linux 2.6.24+): time spent running a virtual CPU for guest operating systems under the control of the Linux kernel.guest_nice(Linux 3.2.0+): time spent running a niced guest (virtual CPU for guest operating systems under the control of the Linux kernel).