Re: SGA Sizing problem
Date: 1995/08/21
Message-ID: <41ascr$kst_at_mindcrime.interstate.net>#1/1
mmarsden_at_netcom.com (Michael Marsden) wrote:
>Parris Geiser (parris_at_walleye.esp.bellcore.com) wrote:
>: Thomas,
>: Thanks for your reply.
>: Yes the scripts that you provide do give what ORACLE thinks
>: is the size of the SGA. What I'm confused about is that the
>: UNIX ipcs -b -m command value is such a different number.
>: Perhaps ipcs is not giving what I thought or ...???
>: Parris
>
>
>: Thomas J Kyte (tkyte_at_us.oracle.com) wrote:
>: > parris_at_walleye.esp.bellcore.com (Parris Geiser) wrote:
>: > >db_block_buffers = 100
>: > >shared_pool = 3,500,000
>: > >log_buffer = 16,384
>: > >block_size = 2048.
>: > >So, the SGA should be: 3,721,184.
>: > >But when I do an ipcs -b -m
>: > >I get 4,892,680.
>: > >The question is: why such a large descrepency?????
>: > > Thanks.
>: > Run the following two queries in your database, they will show you exactly how
>: > the sga is being allocated and what it is being used for.
>
>
>: > compute sum of Value on report
>: > break on report
>: > column value format 999,999,999
>: > select * from v$sga;
>
>
>: > column bytes format 999,999,999
>: > compute sum of bytes on report
>: > select *
>: > from v$sgastat;
>
>
>: > The variables you listed have by far the largest effect on the SGA size but they
>: > are not the only things up there.
>: > Thomas Kyte
>: > tkyte_at_us.oracle.com
>: > Oracle Government
>
>Don't forget, the memory you see used when you issue the 'ipcs' command
>include the block buffer cache (multiply the number of db_block_buffer
>by the db_block_size). This will get you closer to the 4.5 M !
>
>There are, of course a number of other cache's, buffers, message queue
>areas, whatsidoodles and thing-a-me-bobs that are allocated in there
>as well. (log_buffer_size, sort_area_size off the top of my head).
>
>Michael Marsden
>
>
>
>--
>Michael Marsden "It's the car, right ? Chicks dig the car"
>ORACLE Database Consultant -- BATMAN Forever --
>mmarsden_at_netcom.com, mmarsden_at_ozemail.com.au
>Disclaimer: I own the company so I can say what I like !
>
Received on Mon Aug 21 1995 - 00:00:00 CEST