Time field showing Zero in ps command output

Shell Programming and Scripting
1 
  F S      UID   PID  PPID  C PRI NI             ADDR   SZ            WCHAN    STIME TTY       TIME COMD
401 S   catmgr  5748  5742  0 154 20 e0000006d48cd080  133 e0000003fb6e7200 11:22:32 ?         0:00 /opt/ssh/libexec/sftp-server
3401 R   catmgr  5742  5631  0 152 20 e0000005f974fa00  750                - 11:22:31 ?         0:00 sshd: catmgr@notty
421 T   catmgr 14751 18253  0 186 24 e000000685a6c380  327                - 09:33:57 pts/14    0:00 ksh cat_Duplicate_Records_Removal.ksh
421 T   catmgr  3495 18253  0 158 24 e0000009ceca7080  327                - 09:30:09 pts/14    0:00 ksh cat_Duplicate_Records_Removal.ksh
3401 S   catmgr  9317  9152  0 154 20 e000000654b27400  622 e0000003fb6e7080 04:50:51 ?         0:00 sshd: catmgr@notty
1401 T   catmgr  4091     1  0 152 24 e0000005a6abf700  624                -  Apr 23  ?         0:00 ssh catmgr@g4u1993c.houston.hp.com ksh /DI_Data_HU1/infa_shared/cat/CODE/sh/Reporting_Jobs.sh
401 S   catmgr  9558     1  0 158 20 e0000008ae70ad00  331 e00000063bfa4980 09:44:39 ?         0:00 ksh Reporting_Jobs.sh

I am using HP-ux

I dont know why the time field is shown as 0:00 for running process and why '?' is shown for tty field.

anyone please shed some light on this..

thank you

2

The ? means the process is not connected to a controlling terminal.
Since computers are very fast and ps has limited number of significant digits, some small values are rounded down to 0.00 .

For example a process could have .004 seconds of actual cpu usage, which would display as 0.00 Any process that shows in ps has to have used at least a tiny bit of cpu to have been created.

Do you have a problem you are trying to solve?

1 Like
3

yes i have a problem.(I started playing around with PS becasue of the below issue). Can you please suggest an alternative method for 'disown' command as its not supported in my HP-UX
http://www.unix.com/shell-programming-and-scripting/257480-korn-shell-script-stopped-state-while-running-background-2.html#post302942940

4

disown builtin is in ksh93. HP-UX 11.31 and older have ksh88.
Workaround is closing or redirecting all the file handles, at minimum stdin(0), stdout(1), stderr(2).
TIME is accumulated CPU usage. Actual CPU usage is PCPU .
You can display all the times with this:

UNIX95=1 ps -eo pid,user,time,etime,stime,pcpu,args

Average CPU consumption is the quotient (time / etime), (CPU time / Elapsed time).
The stime is an absolute time of the process start, usually less precise than (current_time - etime).

1 Like
5

I believe this link will be of some use

The UNIX School: ps command : what does the TIME indicate?