OS第2次实验报告：创建进程
- 姓名 那宝龙
- 学号 201821121054
- 班级 计算1812
1. 编写程序
在服务器上用VIM编辑器编写一个程序：一个进程创建（fork）两个子进程。给出源代码：
#include<sys/types.h>
#include<unistd.h>
#include<stdio.h>
int main()
{
pid_t ppid;
int i;
for(i=0;i<2;i++）
{
ppid=fork();
if(ppid==0 || ppid<0){
break;
}
}
ifp(ppid<0)
printf("error in fork!");
else if(ppid==0){
printf("Child process,my process id is %d\n",getpid());
}
else{
printf("Parent process,my process id is %d\n",getpid());
}
sleep(100);
return 0;
}
2. 打印进程树
打印1所创建的进程树结构，给出带有自己名字的截图。
提示：
- 使用
unsigned sleep(unsigned seconds)挂起进程，以便打印进程树 - 打印进程树命令
pstree -p pid
3. 解读进程相关信息
(1) ps -ef
使用ps -ef给出所创建进程的信息，并分析每个字段的含义。
UID PID PPID C STIME TTY TIME CMD root 1 0 0 Mar26 ? 00:00:34 /sbin/init root 2 0 0 Mar26 ? 00:00:00 [kthreadd] root 4 2 0 Mar26 ? 00:00:00 [kworker/0:0H] root 6 2 0 Mar26 ? 00:00:00 [mm_percpu_wq] root 7 2 0 Mar26 ? 00:00:35 [ksoftirqd/0] root 8 2 0 Mar26 ? 00:01:00 [rcu_sched] root 9 2 0 Mar26 ? 00:00:00 [rcu_bh] root 10 2 0 Mar26 ? 00:00:00 [migration/0] root 11 2 0 Mar26 ? 00:00:01 [watchdog/0] root 12 2 0 Mar26 ? 00:00:00 [cpuhp/0] root 13 2 0 Mar26 ? 00:00:00 [kdevtmpfs] root 14 2 0 Mar26 ? 00:00:00 [netns] root 15 2 0 Mar26 ? 00:00:00 [rcu_tasks_kthre] root 16 2 0 Mar26 ? 00:00:00 [kauditd] root 17 2 0 Mar26 ? 00:00:00 [khungtaskd] root 18 2 0 Mar26 ? 00:00:00 [oom_reaper] root 19 2 0 Mar26 ? 00:00:00 [writeback] root 20 2 0 Mar26 ? 00:00:00 [kcompactd0] root 21 2 0 Mar26 ? 00:00:00 [ksmd] root 22 2 0 Mar26 ? 00:00:00 [khugepaged] root 23 2 0 Mar26 ? 00:00:00 [crypto] root 24 2 0 Mar26 ? 00:00:00 [kintegrityd] root 25 2 0 Mar26 ? 00:00:00 [kblockd] root 26 2 0 Mar26 ? 00:00:00 [ata_sff] root 27 2 0 Mar26 ? 00:00:00 [md] root 28 2 0 Mar26 ? 00:00:00 [edac-poller] root 29 2 0 Mar26 ? 00:00:00 [devfreq_wq] root 30 2 0 Mar26 ? 00:00:00 [watchdogd] root 34 2 0 Mar26 ? 00:00:02 [kswapd0] root 35 2 0 Mar26 ? 00:00:00 [kworker/u3:0] root 36 2 0 Mar26 ? 00:00:00 [ecryptfs-kthrea] root 78 2 0 Mar26 ? 00:00:00 [kthrotld] root 79 2 0 Mar26 ? 00:00:00 [acpi_thermal_pm] root 80 2 0 Mar26 ? 00:00:00 [scsi_eh_0] root 81 2 0 Mar26 ? 00:00:00 [scsi_tmf_0] root 82 2 0 Mar26 ? 00:00:00 [scsi_eh_1] root 83 2 0 Mar26 ? 00:00:00 [scsi_tmf_1] root 89 2 0 Mar26 ? 00:00:00 [ipv6_addrconf] root 98 2 0 Mar26 ? 00:00:00 [kstrp] root 115 2 0 Mar26 ? 00:00:00 [charger_manager] root 156 2 0 Mar26 ? 00:00:10 [kworker/0:1H] root 169 2 0 Mar26 ? 00:00:00 [ttm_swap] root 272 2 0 Mar26 ? 00:00:00 [raid5wq] root 327 2 0 Mar26 ? 00:00:14 [jbd2/vda1-8] root 328 2 0 Mar26 ? 00:00:00 [ext4-rsv-conver] root 394 1 0 Mar26 ? 00:03:08 /lib/systemd/systemd-journald root 410 2 0 Mar26 ? 00:00:00 [iscsi_eh] root 411 1 0 Mar26 ? 00:00:00 /sbin/lvmetad -f root 421 2 0 Mar26 ? 00:00:00 [ib-comp-wq] root 422 2 0 Mar26 ? 00:00:00 [ib_mcast] root 423 2 0 Mar26 ? 00:00:00 [ib_nl_sa_wq] root 434 2 0 Mar26 ? 00:00:00 [rdma_cm] root 436 1 0 Mar26 ? 00:00:01 /lib/systemd/systemd-udevd systemd+ 803 1 0 Mar26 ? 00:00:00 /lib/systemd/systemd-networkd systemd+ 825 1 0 Mar26 ? 00:00:11 /lib/systemd/systemd-resolved root 909 1 0 Mar26 ? 00:00:01 /lib/systemd/systemd-logind root 918 1 0 Mar26 ? 00:00:03 /usr/bin/lxcfs /var/lib/lxcfs/ syslog 919 1 0 Mar26 ? 00:00:40 /usr/sbin/rsyslogd -n daemon 925 1 0 Mar26 ? 00:00:00 /usr/sbin/atd -f root 929 1 0 Mar26 ? 00:00:00 /usr/bin/python3 /usr/bin/networkd-dispatcher --run-startup-triggers root 933 1 0 Mar26 ? 00:00:45 /usr/lib/accountsservice/accounts-daemon message+ 936 1 0 Mar26 ? 00:00:41 /usr/bin/dbus-daemon --system --address=systemd: --nofork --nopidfile -- root 978 1 0 Mar26 ? 00:00:03 /usr/sbin/cron -f root 994 1 0 Mar26 ? 00:00:00 /usr/bin/python3 /usr/share/unattended-upgrades/unattended-upgrade-shutd root 1011 1 0 Mar26 ? 00:00:22 /usr/lib/policykit-1/polkitd --no-debug ntp 1012 1 0 Mar26 ? 00:00:26 /usr/sbin/ntpd -p /var/run/ntpd.pid -g -u 111:115 root 1013 1 0 Mar26 ? 00:00:59 /usr/sbin/sshd -D root 1157 1 0 Mar26 ttyS0 00:00:00 /sbin/agetty -o -p -- \u --keep-baud 115200,38400,9600 ttyS0 vt220 root 1159 1 0 Mar26 ? 00:31:34 /usr/local/qcloud/YunJing/YDEyes/YDService root 1365 1 0 Mar26 ? 00:00:05 /usr/local/qcloud/stargate/sgagent -d root 1380 1 0 Mar26 ? 00:00:07 barad_agent root 1381 1380 0 Mar26 ? 00:07:40 barad_agent root 1382 1380 0 Mar26 ? 00:37:29 barad_agent root 1446 1 0 Mar26 ? 00:01:04 /usr/local/qcloud/YunJing/YDLive/YDLive root 2550 2 0 10:37 ? 00:00:00 [kworker/u2:0] root 8937 2 0 11:14 ? 00:00:00 [kworker/u2:2] nabaolo+ 9946 1 0 11:19 ? 00:00:00 /lib/systemd/systemd --user nabaolo+ 9947 9946 0 11:19 ? 00:00:00 (sd-pam) root 10547 1013 0 11:22 ? 00:00:00 sshd: nabaolong [priv] nabaolo+ 10641 10547 0 11:22 ? 00:00:00 sshd: nabaolong@pts/0 nabaolo+ 10642 10641 0 11:22 pts/0 00:00:00 -bash nabaolo+ 10674 10642 0 11:22 pts/0 00:00:00 vim myos2.c root 11987 2 0 11:30 ? 00:00:00 [kworker/u2:1] root 11989 2 0 11:30 ? 00:00:00 [kworker/u2:3] root 12018 1013 0 11:30 ? 00:00:00 sshd: zhangyiming [priv] zhangyi+ 12032 1 0 11:30 ? 00:00:00 /lib/systemd/systemd --user zhangyi+ 12033 12032 0 11:30 ? 00:00:00 (sd-pam) zhangyi+ 12120 12018 0 11:30 ? 00:00:00 sshd: zhangyiming@pts/2 zhangyi+ 12122 12120 0 11:30 pts/2 00:00:00 -bash zhangyi+ 12361 12122 0 11:32 pts/2 00:00:00 vim /C:/fork/ffork.c root 12405 1013 0 11:32 ? 00:00:00 sshd: nabaolong [priv] nabaolo+ 12499 12405 0 11:32 ? 00:00:00 sshd: nabaolong@pts/3 nabaolo+ 12500 12499 0 11:32 pts/3 00:00:00 -bash nabaolo+ 12946 12500 0 11:35 pts/3 00:00:00 ps -ef root 15733 1 0 Apr02 tty2 00:00:00 /sbin/agetty -o -p -- \u --noclear tty2 linux root 17340 2 0 01:15 ? 00:00:00 [kworker/0:1] root 22819 1 0 Apr03 tty1 00:00:00 /sbin/agetty -o -p -- \u --noclear tty1 linux root 28757 2 0 02:41 ? 00:00:02 [kworker/0:0]
UID：用户ID
PID：该进程的ID
PPID：进程的父进程ID
C：进程cpu占有率
STIME：进程启动时间
TTY：该进程终端名称
TIME：进程执行时间
CMD：下达的指令
(2) ps -aux
USER PID %CPU %MEM VSZ RSS TTY STAT START TIME COMMAND root 1 0.0 0.5 78484 9484 ? Ss Mar26 0:34 /sbin/init root 2 0.0 0.0 0 0 ? S Mar26 0:00 [kthreadd] root 4 0.0 0.0 0 0 ? I< Mar26 0:00 [kworker/0:0H] root 6 0.0 0.0 0 0 ? I< Mar26 0:00 [mm_percpu_wq] root 7 0.0 0.0 0 0 ? S Mar26 0:35 [ksoftirqd/0] root 8 0.0 0.0 0 0 ? I Mar26 1:00 [rcu_sched] root 9 0.0 0.0 0 0 ? I Mar26 0:00 [rcu_bh] root 10 0.0 0.0 0 0 ? S Mar26 0:00 [migration/0] root 11 0.0 0.0 0 0 ? S Mar26 0:01 [watchdog/0] root 12 0.0 0.0 0 0 ? S Mar26 0:00 [cpuhp/0] root 13 0.0 0.0 0 0 ? S Mar26 0:00 [kdevtmpfs] root 14 0.0 0.0 0 0 ? I< Mar26 0:00 [netns] root 15 0.0 0.0 0 0 ? S Mar26 0:00 [rcu_tasks_kthre] root 16 0.0 0.0 0 0 ? S Mar26 0:00 [kauditd] root 17 0.0 0.0 0 0 ? S Mar26 0:00 [khungtaskd] root 18 0.0 0.0 0 0 ? S Mar26 0:00 [oom_reaper] root 19 0.0 0.0 0 0 ? I< Mar26 0:00 [writeback] root 20 0.0 0.0 0 0 ? S Mar26 0:00 [kcompactd0] root 21 0.0 0.0 0 0 ? SN Mar26 0:00 [ksmd] root 22 0.0 0.0 0 0 ? SN Mar26 0:00 [khugepaged] root 23 0.0 0.0 0 0 ? I< Mar26 0:00 [crypto] root 24 0.0 0.0 0 0 ? I< Mar26 0:00 [kintegrityd] root 25 0.0 0.0 0 0 ? I< Mar26 0:00 [kblockd] root 26 0.0 0.0 0 0 ? I< Mar26 0:00 [ata_sff] root 27 0.0 0.0 0 0 ? I< Mar26 0:00 [md] root 28 0.0 0.0 0 0 ? I< Mar26 0:00 [edac-poller] root 29 0.0 0.0 0 0 ? I< Mar26 0:00 [devfreq_wq] root 30 0.0 0.0 0 0 ? I< Mar26 0:00 [watchdogd] root 34 0.0 0.0 0 0 ? S Mar26 0:02 [kswapd0] root 35 0.0 0.0 0 0 ? I< Mar26 0:00 [kworker/u3:0] root 36 0.0 0.0 0 0 ? S Mar26 0:00 [ecryptfs-kthrea] root 78 0.0 0.0 0 0 ? I< Mar26 0:00 [kthrotld] root 79 0.0 0.0 0 0 ? I< Mar26 0:00 [acpi_thermal_pm] root 80 0.0 0.0 0 0 ? S Mar26 0:00 [scsi_eh_0] root 81 0.0 0.0 0 0 ? I< Mar26 0:00 [scsi_tmf_0] root 82 0.0 0.0 0 0 ? S Mar26 0:00 [scsi_eh_1] root 83 0.0 0.0 0 0 ? I< Mar26 0:00 [scsi_tmf_1] root 89 0.0 0.0 0 0 ? I< Mar26 0:00 [ipv6_addrconf] root 98 0.0 0.0 0 0 ? I< Mar26 0:00 [kstrp] root 115 0.0 0.0 0 0 ? I< Mar26 0:00 [charger_manager] root 156 0.0 0.0 0 0 ? I< Mar26 0:10 [kworker/0:1H] root 169 0.0 0.0 0 0 ? I< Mar26 0:00 [ttm_swap] root 272 0.0 0.0 0 0 ? I< Mar26 0:00 [raid5wq] root 327 0.0 0.0 0 0 ? S Mar26 0:14 [jbd2/vda1-8] root 328 0.0 0.0 0 0 ? I< Mar26 0:00 [ext4-rsv-conver] root 394 0.0 4.2 200704 80032 ? S<s Mar26 3:09 /lib/systemd/systemd-journald root 410 0.0 0.0 0 0 ? I< Mar26 0:00 [iscsi_eh] root 411 0.0 0.0 97708 1680 ? Ss Mar26 0:00 /sbin/lvmetad -f root 421 0.0 0.0 0 0 ? I< Mar26 0:00 [ib-comp-wq] root 422 0.0 0.0 0 0 ? I< Mar26 0:00 [ib_mcast] root 423 0.0 0.0 0 0 ? I< Mar26 0:00 [ib_nl_sa_wq] root 434 0.0 0.0 0 0 ? I< Mar26 0:00 [rdma_cm] root 436 0.0 0.2 45464 3920 ? Ss Mar26 0:01 /lib/systemd/systemd-udevd systemd+ 803 0.0 0.2 80040 4636 ? Ss Mar26 0:00 /lib/systemd/systemd-networkd systemd+ 825 0.0 0.2 70624 4788 ? Ss Mar26 0:11 /lib/systemd/systemd-resolved root 909 0.0 0.3 70700 6000 ? Ss Mar26 0:01 /lib/systemd/systemd-logind root 918 0.0 0.1 636612 2776 ? Ssl Mar26 0:03 /usr/bin/lxcfs /var/lib/lxcfs/ syslog 919 0.0 0.2 263036 4504 ? Ssl Mar26 0:40 /usr/sbin/rsyslogd -n daemon 925 0.0 0.1 28332 2276 ? Ss Mar26 0:00 /usr/sbin/atd -f root 929 0.0 0.8 169784 15056 ? Ssl Mar26 0:00 /usr/bin/python3 /usr/bin/networkd-dispatcher --run-sta root 933 0.0 0.3 287456 5784 ? Ssl Mar26 0:45 /usr/lib/accountsservice/accounts-daemon message+ 936 0.0 0.2 50176 4256 ? Ss Mar26 0:41 /usr/bin/dbus-daemon --system --address=systemd: --nofo root 978 0.0 0.1 30664 2968 ? Ss Mar26 0:03 /usr/sbin/cron -f root 994 0.0 0.9 186632 18124 ? Ssl Mar26 0:00 /usr/bin/python3 /usr/share/unattended-upgrades/unatten root 1011 0.0 0.2 288880 4864 ? Ssl Mar26 0:22 /usr/lib/policykit-1/polkitd --no-debug ntp 1012 0.0 0.1 107776 3432 ? Ssl Mar26 0:26 /usr/sbin/ntpd -p /var/run/ntpd.pid -g -u 111:115 root 1013 0.0 0.3 72296 6068 ? Ss Mar26 0:59 /usr/sbin/sshd -D root 1157 0.0 0.1 15300 2132 ttyS0 Ss+ Mar26 0:00 /sbin/agetty -o -p -- \u --keep-baud 115200,38400,9600 root 1159 0.2 1.8 165940 34040 ? Ssl Mar26 31:35 /usr/local/qcloud/YunJing/YDEyes/YDService root 1365 0.0 0.1 98828 3688 ? Sl Mar26 0:05 /usr/local/qcloud/stargate/sgagent -d root 1380 0.0 0.4 54888 8976 ? S Mar26 0:07 barad_agent root 1381 0.0 0.5 57864 11140 ? S Mar26 7:40 barad_agent root 1382 0.2 0.7 508748 14656 ? Sl Mar26 37:31 barad_agent root 1446 0.0 0.2 103744 5172 ? Ssl Mar26 1:04 /usr/local/qcloud/YunJing/YDLive/YDLive root 2550 0.0 0.0 0 0 ? I 10:37 0:00 [kworker/u2:0] nabaolo+ 9946 0.0 0.4 76616 7548 ? Ss 11:19 0:00 /lib/systemd/systemd --user nabaolo+ 9947 0.0 0.1 112468 3100 ? S 11:19 0:00 (sd-pam) root 10547 0.0 0.3 105684 7180 ? Ss 11:22 0:00 sshd: nabaolong [priv] nabaolo+ 10641 0.0 0.2 107984 5396 ? S 11:22 0:00 sshd: nabaolong@pts/0 nabaolo+ 10642 0.0 0.2 22020 5156 pts/0 Ss 11:22 0:00 -bash nabaolo+ 10674 0.0 0.4 54896 9312 pts/0 S+ 11:22 0:00 vim myos2.c root 11987 0.0 0.0 0 0 ? I 11:30 0:00 [kworker/u2:1] root 11989 0.0 0.0 0 0 ? I 11:30 0:00 [kworker/u2:3] root 12405 0.0 0.3 105684 7168 ? Ss 11:32 0:00 sshd: nabaolong [priv] nabaolo+ 12499 0.0 0.3 107984 5640 ? S 11:32 0:00 sshd: nabaolong@pts/3 nabaolo+ 12500 0.0 0.2 22020 5044 pts/3 Ss 11:32 0:00 -bash root 13167 0.0 0.3 105684 7100 ? Ss 11:36 0:00 sshd: zhangyiming [priv] zhangyi+ 13184 0.0 0.4 76616 7592 ? Ss 11:37 0:00 /lib/systemd/systemd --user zhangyi+ 13185 0.0 0.1 112468 3100 ? S 11:37 0:00 (sd-pam) zhangyi+ 13272 0.0 0.2 107984 5508 ? S 11:37 0:00 sshd: zhangyiming@pts/1 zhangyi+ 13279 0.0 0.2 22020 5124 pts/1 Ss 11:37 0:00 -bash zhangyi+ 13355 0.0 0.5 54896 9420 pts/1 S+ 11:37 0:00 vim test.c nabaolo+ 14020 0.0 0.1 39008 3612 pts/3 R+ 11:42 0:00 ps -aux root 15733 0.0 0.1 15524 1952 tty2 Ss+ Apr02 0:00 /sbin/agetty -o -p -- \u --noclear tty2 linux root 17340 0.0 0.0 0 0 ? I 01:15 0:00 [kworker/0:1] root 22819 0.0 0.1 15524 1924 tty1 Ss+ Apr03 0:00 /sbin/agetty -o -p -- \u --noclear tty1 linux root 28757 0.0 0.0 0 0 ? I 02:41 0:02 [kworker/0:0]
USER:用户名
%CPU:进程的占用的CPU百分比
%MEM:占用的内存的百分比
VSZ;该进程的使用的虚拟內存量
RSS:该进程的占用的固定內存量
STAT:该进程的状态
START/该进程的被触发的启动时间
