一、PROCESS STATE CODES
Here are the different values that the s, stat and state output specifiers (header "STAT" or "S") will display to describe the state of a process.
D Uninterruptible sleep (usually IO)
R Running or runnable (on run queue)
S Interruptible sleep (waiting for an event to complete)
T Stopped, either by a job control signal or because it is being traced.
W paging (not valid since the 2.6.xx kernel)
X dead (should never be seen)
Z Defunct ("zombie") process, terminated but not
reaped by its parent.
For BSD formats and when the stat keyword is used,additional characters may be displayed:
< high-priority (not nice to other users)
N low-priority (nice to other users)
L has pages locked into memory (for real-time and custom IO)
s is a session leader
l is multi-threaded (using CLONE_THREAD, like NPTL pthreads do)
+ is in the foreground process group
translate:
D 无法中断的休眠状态（通常 IO 的进程）；
R 正在运行可中在队列中可过行的；
S 处于休眠状态；
T 停止或被追踪；
W 进入内存交换（从内核2.6开始无效）；
X 死掉的进程 ；
Z 僵尸进程；
< 优先级高的进程
N 优先级较低的进程
L 有些页被锁进内存；
s 进程的领导者（在它之下有子进程）；
l 多进程的（使用 CLONE_THREAD, 类似 NPTL pthreads）；
+ 位于后台的进程组；
Two, give an example
ps -aux | more
USER PID %CPU %MEM VSZ RSS TTY STAT START TIME COMMAND
root 1 0.0 0.0 59184 7500 ? Ss Feb11 106:15 /usr/lib/systemd/testsystemd --switched-root --system --deserialize 22
root 2 0.0 0.0 0 0 ? S Feb11 0:14 [testkthreadd]
root 3 0.0 0.0 0 0 ? S Feb11 8:08 [testksoftirqd/0]
root 5 0.0 0.0 0 0 ? S< Feb11 0:00 [testkworker/0:0H]
root 8 0.0 0.0 0 0 ? S Feb11 6:34 [testmigration/0]
root 9 0.0 0.0 0 0 ? S Feb11 0:00 [testrcu_bh]
root 10 0.0 0.0 0 0 ? S Feb11 242:57 [testrcu_sched]
root 3232 0.0 0.0 0 0 ? SN Feb11 29:09 [testkipmi0]
root 3321 0.0 0.0 98652 876 ? Ssl Feb11 0:12 /usr/sbin/testproxy -D
test 4121 2.6 0.0 0 0 ? Zsl Sep09 3935:10 [testsvr] <defunct>
root 24634 0.0 0.0 0 0 ? D Dec11 0:00 [kworker/6:10]