IDS Forum

RE: Cannot kill session (onmode -z doesn't work)

Posted By: Dirk Cornelis Moolman [ MTN - Innovation Centre ]
Date: Wednesday, 29 June 2011, at 8:01 a.m.

In Response To: Re: Cannot kill session (onmode -z doesn't work) (Fernando Nunes)

We are now running into the same problem again. I tried the "onstat -g stm SID", but it comes back with nothing.

mtnx87.mtn.co.za:/ # onstat -g stm 24416

IBM Informix Dynamic Server Version 10.00.FC8XF -- On-Line -- Up 3 days 12:36:09 -- 157286176 Kbytes

session 24416 ---------------------------------------------------------------
sdblock heapsz statement ('*' = Open cursor)

I ran it for the session taking the most memory again -

mtnx87.mtn.co.za:/ # onstat -g ses | sort -nr -k 8 | more
24416 compans - -1 mtnepp17 1 1104437248 821853816 off
1918648 compans - -1 mtnepp17 1 627732480 627723024 off
213352 root - 393443 mtnepp16 1 12611584 12223256 off
2010236 root - 103699 mtnepp16 1 11874304 11474120 off
1934587 root - 310760 mtnepp16 1 10776576 10772344 off
1900065 root - 17593 mtnepp16 1 10842112 10591824 off
1939737 root - 49782 mtnepp16 1 10203136 9949496 off
1912556 root - 29692 mtnepp16 1 9408512 9191848 off
1949170 root - 56065 mtnepp16 1 9183232 8739384 off
1911515 root - 25919 mtnepp16 1 9027584 8639688 off
1920278 root - 34257 mtnepp16 1 8986624 8380720 off
697526 root - 95294 mtnepp16 1 9277440 8216904 off

> -----Original Message-----
> From: ids-bounces@iiug.org [mailto:ids-bounces@iiug.org] On Behalf Of
> Fernando Nunes
> Sent: Saturday, 25 June 2011 03:24 PM
> To: ids@iiug.org
> Subject: Re: Cannot kill session (onmode -z doesn't work) [24149]
>
> Although 5H is way too much, can you check if the memory decreased
> since you
> run onmode -z?
> In a situation like this even when it works it takes some time (minutes
> not
> hours). I've seen 15m with more or less the same amount of memory in a
> server that was not swapping.
>
> In any case, before you kill the session, run an onstat -g stm SID
> This will show you the prepared statements for the session. Most
> probably
> your application is repeating prepares for one or more statements.
> Most if not all the situations I've seen (I'd say 80%) are from Java
> programs.
> Not that Java is inherently bad, but apparently it becomes easier to
> make
> the above mistake.
>
> By the way, the session does have a PID. It's "-1" which signals it's a
> java
> program (in pure Java code there is not (or there was no...) way to get
> the
> process id. That's why it shows -1
>
> In short: I may not be able to help you to kill that session, but it's
> at
> least as important to see why it happened. If it's the prepare problem
> above
> than the application code must be changed.
>
> Regards.

> On Sat, Jun 25, 2011 at 1:59 PM, Dirk Cornel....
> <moolma_dc@mtn.co.za>wrote:
>
> > IDS 10
> > AIX 5
> >
> > Our server started swapping seriously, and I looked at the sessions
> using
> > the
> > most memory:
> >
> > mtnx87.mtn.co.za:/ # onstat -g ses | sort -nr -k 8 | more
> > 14247 compans - -1 mtnepp17 1 1545867264 1256744912 off
> > 990910 root - 29740 mtnepp16 1 9289728 8973456 off
> > 1010090 root - 38588 mtnepp16 1 8753152 8567712 off
> > 409418 root - 227618 mtnepp16 1 9232384 8371432 off
> > 2062 root - 1982 mtnepp16 1 8732672 8218912 off
> > 1010418 root - 47034 mtnepp16 1 8314880 7973072 off
> > 524172 root - 307888 mtnepp16 1 8572928 7972744 off
> > 1011113 root - 57346 mtnepp16 1 8441856 7966376 off
> >
> > The top one, does not have a corresponding PID. It seems like a
> runaway
> > process that died, or was killed, and the SID stayed behind.
> >
> > I tried killing it (onmode -z), but for the last 5 hours it just
> won't kill
> > .... and I can't shut down the database at this stage (I don't have a
> > downtime
> > window now).
> >
> > Any ideas ?
> >
> > Dirk
> >
> > ________________________________
> > NOTE: This e-mail message is subject to the MTN Group disclaimer see
> > http://www.mtn.co.za/SUPPORT/LEGAL/Pages/EmailDisclaimer.aspx
> >
> >
> >
> >
> ***********************************************************************
> ********
> > Forum Note: Use "Reply" to post a response in the discussion forum.
> >
> >
>
> --
> Fernando Nunes
> Portugal
>
> http://informix-technology.blogspot.com
> My email works... but I don't check it frequently...
>
> --0016e6469ad2c5553904a6893aa3
>
>
> ***********************************************************************
> ********
> Forum Note: Use "Reply" to post a response in the discussion forum.

NOTE: This e-mail message is subject to the MTN Group disclaimer see http://www.mtn.co.za/SUPPORT/LEGAL/Pages/EmailDisclaimer.aspx

Messages In This Thread

• Cannot kill session (onmode -z doesn't work)
  Dirk Cornelis Moolman [ MTN - Innovation Centre ] -- Saturday, 25 June 2011, at 8:59 a.m.
  • Re: Cannot kill session (onmode -z doesn't work)
    Fernando Nunes -- Saturday, 25 June 2011, at 9:24 a.m.
    • RE: Cannot kill session (onmode -z doesn't work)
      Dirk Cornelis Moolman [ MTN - Innovation Centre ] -- Wednesday, 29 June 2011, at 7:57 a.m.
    • RE: Cannot kill session (onmode -z doesn't work)
      Dirk Cornelis Moolman [ MTN - Innovation Centre ] -- Wednesday, 29 June 2011, at 8:01 a.m.
      • Re: Cannot kill session (onmode -z doesn't work)
        Fernando Nunes -- Wednesday, 29 June 2011, at 1:30 p.m.
        • RE: Cannot kill session (onmode -z doesn't work)
          Dirk Cornelis Moolman [ MTN - Innovation Centre ] -- Tuesday, 5 July 2011, at 9:44 a.m.

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