Re: SHARED_POOL_SIZE

From: Connor McDonald <connor_mcdonald_at_yahoo.com>
Date: Wed, 28 Jul 1999 22:01:09 +0800
Message-ID: <379F0D25.3ABA@yahoo.com>

susanne mainz wrote:
>
> Hi,
> in an ORACLE8 DBA course I learned to find out the optimal size for the
> shared pool via the following SQL query:
>
> select
> sum(gets) "DD Gets",
> sum(getmisses) "DD Cache Get Misses",
> 100*(sum(getmisses)/(sum(gets)) "%Reloads"
> from v$rowcache;
>
> Reloads should be less than 1%. Taking the default values for a midddlesized
> DB in the Init.ora the percentage of reloads of my DB are far beyond 1%,
> near 10% in fact.
>
> Is it possible that 1% is only a misprint?
>
> Susanne

As the oracle people say:

"memory doesn't last longer if you don't use it" :-)

It is not uncommon for a machine which is being used solely as an oracle server for numbers around a third of physical memory to be allocated to the shared pool...

Just make sure that your stats as you posted are taken once the database has been in active use for a few hours to allow things to settle down a bit...

If you are using Designer or Replication, then both of use make heavy duty use of PL/SQL so your shared area sizes will need to grow accordingly...

HTH
--

---

Connor McDonald
"These views mine, no-one elses etc etc" connor_mcdonald_at_yahoo.com

"Some days you're the pigeon, and some days you're the statue." Received on Wed Jul 28 1999 - 09:01:09 CDT