Hi,

right.
Only - this may happen with any process, not just oninit.

It depends on OS implementation and possibly configuration.
E.g. on older Solaris versions "ipcrm -m <shmid>" done as
user root removed the SHM segment in any case and
immediately.

But I noticed newer versions of Solaris are more cautious with
this. As long as any process is attached to a SHM segment,
"ipcrm -m ..." will not immediately remove the SHM segment.
Instead it will be marked for deletion. Then upon detach by the
last attached process, the SHM segment will be removed
(without further "ipcrm -m ..." commands).

Therefore it sometimes can happen that SHM segments
"stubbornly refuse to go" because some stray dbaccess
or onbar process is still attached to it (e.g. an SHM
communication segment), thinking it still has to do some
important work. In that case it is necessary to find and
kill such processes.

SHM segments that are just left "lying around" with no process
attached anymore usually are marked with something like "dead".
These should go immediately upon "ipcrm -m ...".

Regards,
Martin
--
Martin Fuerderer
IBM Informix Development Munich, Germany
Information Management

IBM Deutschland GmbH
Chairman of the Supervisory Board: Hans Ulrich Märki
Board of Management: Martin Jetter (Chairman), Rudolf Bauer, Christian
Diedrich, Christoph Grandpierre, Matthias Hartmann, Thomas Fell, Michael
Diemer
Corporate Seat: Stuttgart, Germany; Reg.-Gericht: Amtsgericht Stuttgart,
HRB-Nr.: 14 562 WEEE-Reg.-Nr. DE 99369940

informix-list-bounces@iiug.org wrote on 14.05.2007 18:48:58:
> Greetings,
>
> I also discovered last week deleting the SHM segment - using 'ipcrm' -
may
> not completely remove it. If there is a "D" as the first character
under
> the 'mode' column, the process controlling the memory segments - IDS
> in this case - must be terminated
> before the SHM segments will be removed.
>
> Mike Badar
> ESRI
> 1 International Ct.
> Broomfield, CO 80021
> mbadar@esri.com
> 303-449-7779
> www.esri.com
>
> > -----Original Message-----
> > From: informix-list-bounces@iiug.org
> > [mailto:informix-list-bounces@iiug.org] On Behalf Of Martin Fuerderer
> > Sent: Monday, May 14, 2007 3:22 AM
> > To: Beau Nanaz
> > Cc: informix-list-bounces@iiug.org; informix-list@iiug.org
> > Subject: Re: Confused engine: No SHM segments but thinks it
> > is quiescent
> >
> > Hi,
> >
> > you can look in /INFORMIXTMP directory. (No environment
> > variable in this name.)
> >
> > Also, make sure that when looking for SHM segments ("ipcs
> > -m") you do that as user root. Depending on OS configuration
> > you will simply not see SHM segments of an IDS instance if
> > you are not user root ...
> >
> > Regards,
> > Martin
> > --
> > Martin Fuerderer
> > IBM Informix Development Munich, Germany Information Management
> >
> > IBM Deutschland GmbH
> > Chairman of the Supervisory Board: Hans Ulrich Märki Board of
> > Management: Martin Jetter (Chairman), Rudolf Bauer, Christian
> > Diedrich, Christoph Grandpierre, Matthias Hartmann, Thomas
> > Fell, Michael Diemer Corporate Seat: Stuttgart, Germany;
> > Reg.-Gericht: Amtsgericht Stuttgart,
> > HRB-Nr.: 14 562 WEEE-Reg.-Nr. DE 99369940
> >
> > informix-list-bounces@iiug.org wrote on 13.05.2007 19:38:55:
> > > Hi Family.
> > >
> > > I have a problem I have encountered before, years ago!
> > >
> > > Reasons aside (relating to a failed restore) when I tried
> > to bring up
> > > the engine, it failed. No shared memory segments exist for
> > the server.
> > > However, when I tried to demonstrate the down state of the
> > engine with
> > > a dbacces connection, I get the message:
> > > -27002 No connections are allowed in quiescent mode.
> > > Poor engine! It thinks it is asleep and does not realize it's dead!
> > >
> > > I recall there is a file someplace under $INFORMIXDIR that
> > gives the
> > > current state of the server. The bogus "quiescent" status
> > is coming
> > > from there. All I need to do is delete (OK, rename; Sheesh!
> > > Paranoia! ;-) that file the server will know it is dead.
> > >
> > > Anyone recall what that file is? I found $INFORMIXDIR/etc/.conf.
> > > {INFORMIXSERVER}, a binary data file, but don't know if this is the
> > > one. (Please, no suggestions to delete oninit! ;-) Advice, anyone?
> > >
> > > Thanks much.
> > >
> > > -- J
> > >
> > > _______________________________________________
> > > Informix-list mailing list
> > > Informix-list@iiug.org
> > > http://www.iiug.org/mailman/listinfo/informix-list
> >
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> >
> >
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