Re: 2GB limit for SGAs

Stephan Bressler <sbresslerx_no_spam_at_arcor.de> wrote in message news:<c9408u$lka$1_at_news.mch.sbs.de>...
> ...
> The 32bit address limit is 4GB (not 2gb), but the address range has to
> be split into kernel and user address range. The split is highly
> processor and OS dependent.
> On solaris (32 and 64 bit), it's no problem to use a 3GB sga with 32bit
> oracle (see below. You can clearly see that the sga is ~2.8GB with
> oracle 9.2 32bit).
> Regards
> Stephan
>
> $ file $ORACLE_HOME/bin/oracle
> /oracle/FSP1/orav92_32/bin/oracle: ELF 32-bit MSB executable SPARC
> Version 1, dynamically linked, not stripped
>
> $ uname -a
> SunOS mybox 5.8 Generic_108528-29 sun4us sparc FJSV,GPUSC-M
>
>
> $sqlplus "/ as sysdba"
> SQL*Plus: Release 9.2.0.2.0 - Production on Thu May 27 07:53:29 2004
> Copyright (c) 1982, 2002, Oracle Corporation. All rights reserved.
> Connected to an idle instance.
>
> SQL> startup nomount
> ORACLE instance started.
>
> Total System Global Area 2814465276 bytes
> Fixed Size 455932 bytes
> Variable Size 1174405120 bytes
> Database Buffers 1638400000 bytes
> Redo Buffers 1204224 bytes
> SQL> exit
> Disconnected from Oracle9i Enterprise Edition Release 9.2.0.2.0 - Production
> JServer Release 9.2.0.2.0 - Production
> 02 ecrmtdb:/oracle/FSP1
> 02 ecrmtdb:/oracle/FSP1

Stephan,

Could you show us the output of

ipcs -b (if multiple instances running, let us know) sysdef | grep -i shm
pmap -x <pmon pid> | grep shmid
nm $ORACLE_HOME/bin/oracle | grep sgabeg

Do you see any warning or error in alert.log? I'd like to see if the SGA is split into multiple segments. Can you do this on older version Oracle such as 8i? Thanks.

Yong Huang Received on Thu May 27 2004 - 18:14:40 CDT