psutil.cpu_times（）在python中返回的每个参数的含义是什么？

Question

The output of the command psutil.cpu_times( ) is like this:

scputimes(user=2298.7, nice=20.11, system=728.58, idle=49415.86, iowait=153.26, irq=0.08, softirq=16.78, steal=0.0, guest=0.0, guest_nice=0.0)

The user and system values are for how long the CPU has spent in user vs system operations, but what is the meaning of the other returned values?

And how can I get the number of context switches that happed in the last 3 minutes for example?

Answer 1

Those are cumulative numbers therefore they represent the amount of time the CPU has spent since the system has started. As for the meaning of each value (idle, iowait, etc.) take a look at "man proc":

cpu  3357 0 4313 1362393
     The  amount of time, measured in units of USER_HZ (1/100ths of a second on most
     architectures, use sysconf(_SC_CLK_TCK) to obtain the right  value),  that  the
     system spent in various states:

     user   (1) Time spent in user mode.

     nice   (2) Time spent in user mode with low priority (nice).

     system (3) Time spent in system mode.

     idle   (4) Time spent in the idle task.  This value should be USER_HZ times the
            second entry in the /proc/uptime pseudo-file.

     iowait (since Linux 2.5.41)
            (5) Time waiting for I/O to complete.

     irq (since Linux 2.6.0-test4)
            (6) Time servicing interrupts.

     softirq (since Linux 2.6.0-test4)
            (7) Time servicing softirqs.

     steal (since Linux 2.6.11)
            (8) Stolen time, which is the time spent in other operating systems when
            running in a virtualized environment

     guest (since Linux 2.6.24)
            (9)  Time  spent running a virtual CPU for guest operating systems under
            the control of the Linux kernel.

     guest_nice (since Linux 2.6.33)
            (10) Time spent running a niced guest (virtual CPU for  guest  operating
            systems under the control of the Linux kernel).

Answer 2

As you said user and system are respectively the time spent in user or systems operations, nice is the niceness (priority) of the process.

According to the doc the function psutil.get_num_ctx_switches() returns the number of voluntary and involuntary context switches performed by the process (see Documentation )