Re: dbbackuptrigger & paging space

We had a similiar problem a month ago, where the recovery log would not
reset despite multiple backup.  Only when the ADSM server was recycled, did
the recovery log reset.  I have an open problem with IBM on this, and this
is their reply from IBM Level 2 up to now:

Received following information from Development:

I am not aware of any problems concerning the reduction ofthe recovery log
following a full database backup.  What is likely happening is that there
was a transaction still open with a recovery log record still open.
Following the database backup, the recovery log could not be synched past
that point and could not be reduced.  Sounds like the transaction was
orphaned.  If they have this problem again, have them do the following
commands:

SHOW  LOGSTATS, SHOW LOGSEGTABLE, SHOW LOGVARS, SHOW THREADS, Q PROCESS


We were running ADSM/MVS v31.1.3 then, and have since upgraded to v3.1.2.14
(with fixtest).  Have not seen that problem yet.  The other problem we have
is that our recovery log is 5.4 GB already, and the ADSM/MVS ADSM Admin
Guide documents the limit as 5.5 GB maximum for the recovery log.  Has
anyone tried a recovery log greater than 5.5 GB.

Regards,

Terence

        -----Original Message-----
        From:   Werner Baur [SMTP:Werner.Baur AT LRZ-MUENCHEN DOT DE]
        Sent:   Thursday, February 11, 1999 8:49 AM
        To:     ADSM-L AT VM.MARIST DOT EDU
        Subject:        Re: dbbackuptrigger & paging space

        I have a similar problem with one of our larger servers.
        The server holds a 50 GB database.

        The latest crash occured this morning. The recovery log exceeded the
        limit of 75%. The triggered database backup did not free up
sufficient space,
        db backup started again and so on. Normally we stop the server
before we
        run out of recovery log space. This morning, 5:00 am, nobody was
present to do
        it.
        So the server crashed. After the restart everything was fine.

        The server holds a 50 GB database. The recovery log is 4 GB.
        At the time of the first crash the trigger was set to 50%.
Following the
        recommendation of the error message text we increased the trigger to
75%. All
        the same the db looping continued.
        I have an open record for this problem.

        Werner


        Joel Fuhrman wrote:

        > AIX 4.2.1
        > ADSM Server level 3.1.2.13
        >
        > I have defined my dbbackuptrigger to be 50%.  The max log shows
57%.  When
        > the trigger was activated, it failed to reduce the log to less
than 50%.  Is
        > this a bug?
        >
        > As the backups continued, it triggered additional dbbackups.
Eventually, the
        > activity log is flooded with these messages:
        > 1999-02-09 03:06:40      ANR9999D logread.c(179): Attempt to read
LSN
        >                           18717.193.3351 below trunc LSN
18768.171.991.
        >
        > Finally, the system paging space filled and processes were killed
by AIX
        > which had the effect of killing ADSM.  Has any one else seen this
behavior?
        >
        > ADSM is the only thing running on this system.  The paging space
is normally
        > only 22% used.

        --
        Werner Baur                    Tel.:++49-89-28928781
        Leibniz-Rechenzentrum           Fax:++49-89-2809460
        Barer Str. 21                mailto:baur AT lrz DOT de
        D-80333 Muenchen, Germany      http://www.lrz.de