proc_stat(5) File Formats Manual proc_stat(5)

/proc/stat - kernel system statistics

/proc/stat
kernel/system statistics. Varies with architecture. Common entries include:
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 ("cpu" line) or the specific CPU ("cpuN" line) spent in various states:
(1) Time spent in user mode.
(2) Time spent in user mode with low priority (nice).
(3) Time spent in system mode.
(4) Time spent in the idle task. This value should be USER_HZ times the second entry in the /proc/uptime pseudo-file.
(5) Time waiting for I/O to complete. This value is not reliable, for the following reasons:
The CPU will not wait for I/O to complete; iowait is the time that a task is waiting for I/O to complete. When a CPU goes into idle state for outstanding task I/O, another task will be scheduled on this CPU.
On a multi-core CPU, the task waiting for I/O to complete is not running on any CPU, so the iowait of each CPU is difficult to calculate.
The value in this field may decrease in certain conditions.
(6) Time servicing interrupts.
(7) Time servicing softirqs.
(8) Stolen time, which is the time spent in other operating systems when running in a virtualized environment
(9) Time spent running a virtual CPU for guest operating systems under the control of the Linux kernel.
(10) Time spent running a niced guest (virtual CPU for guest operating systems under the control of the Linux kernel).
The number of pages the system paged in and the number that were paged out (from disk).
The number of swap pages that have been brought in and out.
This line shows counts of interrupts serviced since boot time, for each of the possible system interrupts. The first column is the total of all interrupts serviced including unnumbered architecture specific interrupts; each subsequent column is the total for that particular numbered interrupt. Unnumbered interrupts are not shown, only summed into the total.
(major,disk_idx):(noinfo, read_io_ops, blks_read, write_io_ops, blks_written)
(Linux 2.4 only)
The number of context switches that the system underwent.
boot time, in seconds since the Epoch, 1970-01-01 00:00:00 +0000 (UTC).
Number of forks since boot.
Number of processes in runnable state. (Linux 2.5.45 onward.)
Number of processes blocked waiting for I/O to complete. (Linux 2.5.45 onward.)
softirq 229245889 94 60001584 13619 5175704 2471304 28 51212741 59130143 0 51240672
This line shows the number of softirq for all CPUs. The first column is the total of all softirqs and each subsequent column is the total for particular softirq. (Linux 2.6.31 onward.)

proc(5)

2024-05-02 Linux man-pages 6.9.1