Re: ASMM question
From: Chuck <skilover_nospam_at_bluebottle.com>
Date: Thu, 03 Apr 2008 21:59:32 GMT
Message-ID: <8rcJj.12748$Re7.9023@trnddc04>
>> 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
>> $sgastat you'll find it agrees with the sga_target_size setting, not
>> with the sga_max_size value.
>>
>> David Fitzjarrell- Hide quoted text -
>>
>> - Show quoted text -
Date: Thu, 03 Apr 2008 21:59:32 GMT
Message-ID: <8rcJj.12748$Re7.9023@trnddc04>
Mark D Powell wrote:
> 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 --
Thanks all Received on Thu Apr 03 2008 - 16:59:32 CDT