Re: DBMS_STATS.GATHER_SYSTEM_STATS samples only BADSTATS



As far as I know, there is only one thing that
actually results in BADSTATS, and that's an
absence of any single block reads in the time
period.  (But there may be other oddities that
could be version dependent - like multiblock
read times being faster than single block read
times).

What do you get from
   select * from sys.aux_stats$

Regards

Jonathan Lewis

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----- Original Message ----- From: "Radoulov, Dimitre" <cichomitiko@xxxxxxxxx>
To: <oracle-l@xxxxxxxxxxxxx>
Sent: Wednesday, December 07, 2005 9:24 PM
Subject: DBMS_STATS.GATHER_SYSTEM_STATS samples only BADSTATS


The same 9.2.0.4 instance on Solaris 8 (do you remember the "hash join vs nested loops" thread :))
Trying to gather system statistics in a period with common workload, CPU load 30-70%, only one instance on this node.
I get only BADSTATS.

Metalink says that we have BADSTATS when:

=> collection is completed but not pertinent, because there was no workload
that could justify any statistics

  => start the collection again when the workload is relevant.

Tried with interval 5 min,15 min, 1h, 2h, 8h, and I get only BADSTATS.
Tried auto(interval)and manual(start/stop) mode, always BADSTATS.


I'll try with an interval > 8h, but, meanwhile, any suggestion is welcome.



Regards,
Dimitre Radoulov





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