查看

查看当前所有进程

$ ps -ef
UID         PID   PPID  C STIME TTY          TIME CMD
root          1      0  0 06:59 ?        00:00:02 /usr/lib/systemd/systemd --switched-root --system --
root          2      0  0 06:59 ?        00:00:00 [kthreadd]
root          3      2  0 06:59 ?        00:00:00 [ksoftirqd/0]

实时查看进程状态及 CPU 占用

$ top
top - 09:24:05 up  2:24,  2 users,  load average: 0.00, 0.01, 0.04
Tasks: 175 total,   1 running, 174 sleeping,   0 stopped,   0 zombie
%Cpu(s):  0.1 us,  0.0 sy,  0.0 ni, 99.9 id,  0.0 wa,  0.0 hi,  0.0 si,  0.0 st
KiB Mem :   999964 total,    66488 free,   661372 used,   272104 buff/cache
KiB Swap:  1048572 total,  1046440 free,     2132 used.   120096 avail Mem

   PID USER      PR  NI    VIRT    RES    SHR S  %CPU %MEM     TIME+ COMMAND                         
    36 root      20   0       0      0      0 S   0.3  0.0   0:02.48 kworker/0:1                     
    80 root      20   0       0      0      0 S   0.3  0.0   0:00.83 kworker/3:1                     
  2473 mysql     20   0 1888520 379700  10168 S   0.3 38.0   0:22.66 mysqld                          
     1 root      20   0  193628   6396   3632 S   0.0  0.6   0:02.58 systemd                         
     2 root      20   0       0      0      0 S   0.0  0.0   0:00.00 kthreadd       

查看守护进程

$ systemctl list-units
UNIT                                  LOAD   ACTIVE SUB       DESCRIPTION
 proc-sys-fs-binfmt_misc.automount     loaded active waiting   Arbitrary Executable File Formats File
 -.mount                               loaded active mounted   /
 boot.mount                            loaded active mounted   /boot
 dev-hugepages.mount                   loaded active mounted   Huge Pages File System
 dev-mqueue.mount                      loaded active mounted   POSIX Message Queue File System
 home.mount                            loaded active mounted   /home
 proc-fs-nfsd.mount                    loaded active mounted   NFSD configuration filesystem
 run-user-1000.mount                   loaded active mounted   /run/user/1000
 run-user-42.mount                     loaded active mounted   /run/user/42