cutime 和 cstime jiffies 是否也包括子进程？

Question

在文件 /proc/[PID]/stat 中，值 cutime 和 cstime（该文件的第 14 和 15 个元素）是带有子元素的 jiffies，这是否意味着进程的子元素？

int     cutime;                   /** user mode jiffies with childs **/
int     cstime;                   /** kernel mode jiffies with childs **/

这是否意味着 jiffies 也包括进程的子进程？

Answer 1

cutime 和 cstime 的含义记录在 man 5 proc

cutime

Amount of time that this process’s waited-for children have been scheduled in user mode, measured in clock ticks...

cstime

Amount of time that this process’s waited-for children have been scheduled in kernel mode, measured in clock ticks...

utime 和 stime 测量 CPU 进程创建的 children 时间。

cutime 和 cstime 是进程创建的所有 children（及其 children...）的 CPU 次之和.不包括utime和stime这个过程，只是children时间。

请注意，当进程使用 CPU 时，utime 和 ctime 会在线更新，但是 child 时会更新 cutime 和 cstime ] 退出，进程为此 child.

调用 wait

编辑 - @txs 的实验，因为 @txs 不相信：

显示进程统计信息的简单脚本：

$ cat ./procstat.sh 6668
while sleep 1
do
   cat /proc//stat | awk '{ print "utime:", , "stime:", , "cutime:" , "cstime:",  }'
done

两个终端，一个正在运行ning脚本，另一个执行耗时处理。我测量了一个 bash 过程。我在测量bash中开始了一个无限循环。 utime 不断增加。然后我中断了循环并开始了 child bash 进程和运行 child 进程中的无限循环。什么都没有改变，但是当我中断进程并退出 child bash 时，cutime 立即改变了。

 $ ps                           +
   PID TTY          TIME CMD    |
 10178 pts/2    00:00:00 bash   |
 10197 pts/2    00:00:00 ps     |
                                |  $ ./procstat.sh 10178
                                |  utime: 2 stime: 1 cutime:1 cstime: 3
                                |  utime: 2 stime: 1 cutime:1 cstime: 3
                                |  utime: 2 stime: 1 cutime:1 cstime: 3
                                |  utime: 3 stime: 1 cutime:1 cstime: 3
                                |  utime: 3 stime: 1 cutime:1 cstime: 3
                                |  utime: 3 stime: 1 cutime:1 cstime: 3
 $ while true; do true; done    |  utime: 49 stime: 1 cutime:1 cstime: 3
                                |  utime: 137 stime: 1 cutime:1 cstime: 3
                                |  utime: 209 stime: 1 cutime:1 cstime: 3
                                |  utime: 296 stime: 1 cutime:1 cstime: 3
                                |  utime: 391 stime: 1 cutime:1 cstime: 3
 ^C                             |  utime: 477 stime: 1 cutime:1 cstime: 3
                                |  utime: 521 stime: 1 cutime:1 cstime: 3
                                |  utime: 521 stime: 1 cutime:1 cstime: 3
                                |  utime: 521 stime: 1 cutime:1 cstime: 3
 $ bash                         |  utime: 522 stime: 1 cutime:1 cstime: 3
                                |  utime: 522 stime: 1 cutime:1 cstime: 3
                                |  utime: 522 stime: 1 cutime:1 cstime: 3
                                |  utime: 522 stime: 1 cutime:1 cstime: 3
 $ while true; do true; done    |  utime: 522 stime: 1 cutime:1 cstime: 3
                                |  utime: 522 stime: 1 cutime:1 cstime: 3
                                |  utime: 522 stime: 1 cutime:1 cstime: 3
                                |  utime: 522 stime: 1 cutime:1 cstime: 3
                                |  utime: 522 stime: 1 cutime:1 cstime: 3
 ^C                             |  utime: 522 stime: 1 cutime:1 cstime: 3
                                |  utime: 522 stime: 1 cutime:1 cstime: 3
                                |  utime: 522 stime: 1 cutime:1 cstime: 3
 $ exit                         |  utime: 522 stime: 1 cutime:623 cstime: 6
                                |  utime: 522 stime: 1 cutime:623 cstime: 6
                                |  utime: 522 stime: 1 cutime:623 cstime: 6
                                |  utime: 522 stime: 1 cutime:623 cstime: 6
                                +  utime: 522 stime: 1 cutime:623 cstime: 6

cutime 和 cstime jiffies 是否也包括子进程？

Do the cutime and cstime jiffies include the child processes as well?

linux

stat

proc