Re: Killing a zombie process?

[Paul Goyette <paul%vps1.whooppee.com@localhost>]

On Thu, 1 Oct 2015, Robert Elz wrote:

>    Date:        Wed, 30 Sep 2015 18:03:03 +0700
>    From:        Robert Elz <kre%munnari.OZ.AU@localhost>
>    Message-ID:  <16072.1443610983%andromeda.noi.kre.to@localhost>
>
>  | I think I'd start with the proc structure of the zombie itself,
>
> Even before that, you might want to check whether the process truly is
> a zombie, or just dead - ps prints both as 'Z' - modifying (temporarily)
> ps to show dead processes differently (maybe just z instead of Z) might
> reveal that the zombie in question hasn't actually putrified yet, and is
> just a corpse.

Interesting idea.  I'm applying the following patch to ps/print.c so it 
will print a ZZ state for LSDEAD (vs only one Z for LSZOMB)

Index: print.c
===================================================================
RCS file: /cvsroot/src/bin/ps/print.c,v
retrieving revision 1.123
diff -u -p -r1.123 print.c
--- print.c     15 Nov 2014 01:58:34 -0000      1.123
+++ print.c     30 Sep 2015 22:44:08 -0000
@@ -513,6 +513,9 @@ state(void *arg, VARENT *ve, enum mode m
                *cp = 'O';
                break;

+       case LSDEAD:
+               *cp++ = 'Z';
+               /* FALLTHRU */
        case LSZOMB:
                *cp = 'Z';
                is_zombie = 1;



> Dead state isn't supposed to persist for long (processes should rot quickly)
> but while in that state, the process is not yet ready for reaping.
>
> Of course, even if this is what is happening, the question of what it is
> waiting for still remains.   Or maybe the processes are just waiting for
> Oct 31 ?

:)



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