linux - 如何计算Linux中一个进程及其所有子进程的CPU利用率？

Question

我想知道 Linux 中某个进程及其所有子进程在固定时间段内的 CPU 利用率。

更具体地说，这是我的用例:

有一个等待用户请求执行程序的进程。为了执行程序，这个进程调用子进程(一次最多 5 个)并且每个子进程执行这些提交的程序中的 1 个(假设用户一次提交 15 个程序)。因此，如果用户提交 15 个程序，则将运行 3 批，每批 5 个子进程。子进程在完成程序执行后立即被终止。

我想知道这 15 个程序执行期间父进程及其所有子进程的 CPU 使用率百分比。

是否有使用 top 或其他命令执行此操作的简单方法？ (或者我应该附加到父进程的任何工具。)

Answer 1

您可以在 /proc/PID/stat 中找到此信息，其中 PID 是您父进程的进程 ID。假设父进程等待其子进程，则可以根据 utime、stime、cutime 和 cstime< 计算总 CPU 使用率/em>:

utime %lu

Amount of time that this process has been scheduled in user mode, measured in clock ticks (divide by sysconf(_SC_CLK_TCK). This includes guest time, guest_time (time spent running a virtual CPU, see below), so that applications that are not aware of the guest time field do not lose that time from their calculations.

stime %lu

Amount of time that this process has been scheduled in kernel mode, measured in clock ticks (divide by sysconf(_SC_CLK_TCK).

cutime %ld

Amount of time that this process's waited-for children have been scheduled in user mode, measured in clock ticks (divide by sysconf(_SC_CLK_TCK). (See also times(2).) This includes guest time, cguest_time (time spent running a virtual CPU, see below).

cstime %ld

Amount of time that this process's waited-for children have been scheduled in kernel mode, measured in clock ticks (divide by sysconf(_SC_CLK_TCK).

参见 proc(5) manpage了解详情。