Re: Yet another ORA-01555 question

Hello,

"Andrew Metcalfe" <chicagoandy_at_hotmail.com> wrote in message news:a2588ec3.0403301134.62fb9492_at_posting.google.com...
> While attempting to troubleshoot a ORA-01555 error, I noticed that I
> have some odd rollback sizes.
>
> NAME TABLESPACE Extents Size(M)
> RBS01 RBS 30 15
> RBS02 RBS 9 4
> RBS03 RBS 31 15.5
>
> The ORA-01555 error specified that RBS02 was too small.
>
> In DBA Studio, if I click into the different segments storage page, I
> see the same setting on each segment.
>
> Initial Size: 512 K
> Next Size: 512 K
> Optimal Size: 4096 K
>
> Minimum Number: 8
> Maximum Number: 4096
>
> If all the segments have the same storage specifications, why would
> one be so radically smaller?

1. This is a funny question, really, because you asked Oracle yourself to shrink the RBS to its optimal size of 4 MB and Oracle obeyed.
   >
   > Why hasn't RBS02 grown the same as 01 and 03?
   
2. There was no long running insert/update/delete transaction which would have caused the segment to grow, that's all.
3. The RBS segments should be sized properly (equi-sized) using the information from, say, statspack so that they were able to accomodate the amount of undo gerated during a typical db load without wrapping arround and over-writing the information required by your longest running query. The OPTIMAL parameter is generally considered harmful. Probably you ought to get rid of it.

>
> Thanks,
>
> _Am
Received on Tue Mar 30 2004 - 16:52:46 CST