Re: Tuning: which applications are writing too much

From: Gerard H. Pille <ghp_at_skynet.be>
Date: Sat, 04 Mar 2006 16:45:18 +0100
Message-ID: <4409b5fc$0$24766$ba620e4c@news.skynet.be>

Jonathan Lewis wrote:
> "Gerard H. Pille" <ghp_at_skynet.be> wrote in message
> news:44098a6f$0$31480$ba620e4c_at_news.skynet.be...
>

>>Hallo,
>>
>>our applications - or some of them - are generating more data than our 
>>hardware can stomach.  The question is of course which ones.  Should be 
>>easy to answer if I can determine which tables are written to most.
>>
>>Don't tell me to RTFM, I know all about the F, and I'm starting with the 
>>Oracle manuals the minute I've posted this.
>>
>>Any hints are well come, even the obvious ones, I can always have 
>>overlooked something stupid, haven't been doing any general tuning for 
>>quite a while now.
>>
>>Thanks,
>>
>>Gerard
>>
>>PS: Most of the databases are 9.2.0.7, all are version 9.

>
>
>
> Since you are on 9i, you can make use of v$segstat.
> For each active segment it holds a dozen or so stats,
> the names are listed in v$segstat_name. These inclue:
>
> db block changes
> physical writes
> physical writes direct
>
> Be a little cautious with v$segstat, using it used to cause
> a memory leak in the SGA, but an "order by" clause seemed
> to stop the leak. Select where value greater than some sensible
> limit for the statistic you want.
>
> Don't use v$segment_statistics - which is the expensive version
> of the same thing.
>
>

Thanks Jonathan, I believe that is what I'm looking for.

Gerard Received on Sat Mar 04 2006 - 09:45:18 CST