Re: Killing a zombie process?

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

On Thu, 24 Sep 2015, Paul Goyette wrote:

> > > Yup, my zombie's parent PPID==1
> > >
> > > >   If init is really its parent, check its "ps axl" output and
> > > > check its WCHAN. If it isn't "wait", maybe run "ktruss -p 1" to
> > > > get an idea of what it is doing instead of wait*() calls.
> > >
> > > See ps output above;  init's WCHAN==wait
> > >
> > > So no clue on why it's not getting around to reaping child 27237.
> >
> > I would try sending init a HUP, which should rescan /etc/ttys and not
> > really do anything.  But it will then call wait(2) again, and if there
> > was a glitch where init was already in wait and the offending process's
> > transition to zombie and ppid==1 didn't cause a wakeup, then it may
> > resolve.
>
> No luck...  I HUPed init, but the zombie is still there.
>
> # kill -HUP 1
> # ps axl | grep ' Z '
>   0 27237     1     0   0  0       0      0 -       Z    pts/2- 0:00.00 (sh)

Well, it happened again!

I rebooted earlier today, and then deinstalled and rebuilt about 40 
packages within the pkgsrc/sysutils/mksandbox environment (all with 
MAKE_JOBS=3 enabled).  After all packages were rebuilt, I exit from the 
sandbox and run ./sandbox/dismount and get the error

	umount: /sandbox/bin: Device busy

Sure enough, there's a new Zombie process, and its parent seems to be 
init (PPID==0)

	# ps axl | grep ' Z '
	   0 23848 2812    0  85  0   4360    164 pipe_rd R+   pts/2  0:00.00 grep  Z
	   0 25439    1    0   0  0      0      0 -       Z    pts/2  0:00.00 (sh)

HUPing init still doesn't help.

So, I'm pretty sure that there's a bug somewhere, but haven't a clue on 
where to start looking.



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| Paul Goyette     | PGP Key fingerprint:     | E-mail addresses:       |
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