Re: ASMM question

On Apr 2, 11:58 am, "fitzjarr..._at_cox.net" <fitzjarr..._at_cox.net> wrote:
> On Apr 2, 10:56 am, "fitzjarr..._at_cox.net" <fitzjarr..._at_cox.net> wrote:
>
>
> > On Apr 2, 10:49 am, Chuck <skilover_nos..._at_bluebottle.com> wrote:
>
> > > sga_target_size = 4g
> > > sga_max_size = 6g
>
> > > When the instance starts, how much memory will it try to allocate? 6g or
> > > 4g?
>
> > > If I run "show sga" on the instance it says total sga size is 6g. If I
> > > run "ipcs -ma" on the o/s (solaris 10) it shows the shared memory
> > > segment as being only 4g.
>
> > > I'm a little confused as to what's really being allocated as there seems
> > > to be some contradiction here.
>
> > > TIA.
>
> > ipcs reports what is actually allocated, which is the
> > sga_target_size.  sga_max_size is your 'wiggle room' for dynamic
> > adjustments.
>
> > David Fitzjarrell
>
> To add to my last post, show sga reports the maximum size the SGA can
> attain, not the actual sga allocation.  I expect that if you look at v
> $sgastat you'll find it agrees with the sga_target_size setting, not
> with the sga_max_size value.
>
> David Fitzjarrell- Hide quoted text -
>
> - Show quoted text -

Be advised that this feature is platform dependend and on some platforms the full amount of shared memory still has to be acquired on startup. On these platforms the sga_target should = the sga_max.

Check your platform specific documentation.

HTH -- Mark D Powell -- Received on Wed Apr 02 2008 - 11:06:55 CDT