Re: PGA_AGGREGATE_TARGET question

From: Niall Litchfield <n-litchfield_at_audit-commission.gov.uk>
Date: Mon, 18 Aug 2003 09:14:53 +0100
Message-ID: <3f408afe$0$15031$ed9e5944@reading.news.pipex.net>

"Richard Foote" <richard.foote_at_bigpond.com> wrote in message news:sOe%a.35716$bo1.4970_at_news-server.bigpond.net.au...
> > Hi Richard

<snip>
> >
> > I *believe* that whether or not Oracle pre-allocates PAT is platform
> > dependent, I'm pretty sure that on Windows at least you get the memory
up
> > front.
> >
> Hi Niall
>
> No, that's not correct (try setting it to say 20G on a 512M box and see
how
> much memory is allocated... ;).

You are correct it was SGA_MAX_SIZE I was thinking of.

SQL> startup
ORACLE instance started.

Total System Global Area 110173444 bytes

Fixed Size                   453892 bytes
Variable Size              88080384 bytes
Database Buffers           20971520 bytes
Redo Buffers                 667648 bytes

Database mounted.
Database opened.
SQL> alter system set sga_max_size=512m scope=spfile;

System altered.

SQL> alter system checkpoint;

System altered.

SQL> shutdown abort;
ORACLE instance shut down.
SQL> startup
ORACLE instance started.

Total System Global Area 537993216 bytes

Fixed Size                   454656 bytes
Variable Size             511705088 bytes
Database Buffers           25165824 bytes
Redo Buffers                 667648 bytes

Database mounted.
Database opened.
SQL> However on this same system the actual memory requested by Oracle from Windows appears to be 170Mb (per task manager. & which is still too much on a 256mb laptop :( ), so maybe I was just entirely incorrect.

-- 
Niall Litchfield
Oracle DBA
Audit Commission UK
Cheers
Niall

Received on Mon Aug 18 2003 - 03:14:53 CDT