Sinardy, you've attended wrong database tuning course. You need free memory in your shared pool.
There is no such thing as "sga fragmentation" unless there is not enough free memory to satisfy average
request. While oracle is not monitoring the size of an average shared pool request. you have things
like session_uga_memory and session_pga_memory in v$mystat. In v9 there is also "session_stored_procedure_space".
If the instance doesn't have enough room to load the next thing to execute (SQL, PL/SQL, Java), it will have
to make room. Generally speaking, making room hurts. You want to have enough room to load your
stuff into the shared pool and then some. That "room" is also known as "free space". Look into the tuning manual on the
OTN and make sure that your buffer cache hit ratio is high enough (sorry folks, I couldn't resist).
On 2003.12.15 23:19, Sinardy Xing wrote:
> Hi all,
>
> Why free memory in v$sgastat is a symptom of the fragmentation?
>
> Why these "free memory" are more properly thought of as wasted space?
>
>
>
> Thanks
>
> Sinardy
>
--
Mladen Gogala
Oracle DBA
--
Please see the official ORACLE-L FAQ: http://www.orafaq.net
--
Author: Mladen Gogala
INET: mgogala_at_adelphia.net
Fat City Network Services -- 858-538-5051 http://www.fatcity.com
San Diego, California -- Mailing list and web hosting services
---------------------------------------------------------------------
To REMOVE yourself from this mailing list, send an E-Mail message
to: ListGuru_at_fatcity.com (note EXACT spelling of 'ListGuru') and in
the message BODY, include a line containing: UNSUB ORACLE-L
(or the name of mailing list you want to be removed from). You may
also send the HELP command for other information (like subscribing).
Received on Mon Dec 15 2003 - 22:54:26 CST
