Re: Mac OS X shared_buffers not same as postgresql.conf file

On 09/23/2011 02:33 PM, Neil Tiffin wrote:
> I have shared_buffers in the config file set for 32 MB and pgAdmin
> reports a value of 32 MB, but pgAdmin also says the current value is
> 4096.  Can anyone point me to any docs about why the current value
> may be different than the config value?  Temp_buffers are the same
> way, config file 8MB, but current value in pgAdmin is 1024?

Internally shared_buffers is tracked as number of 8K pages.

postgres=# show shared_buffers;
 shared_buffers
----------------
 32MB
(1 row)

postgres=# select setting from pg_settings where name='shared_buffers';
 setting
---------
 4096
(1 row)

postgres=# select 4096 * 8 / 1024 as MB;
 mb
----
 32
(1 row)

HTH,

Joe

--
Joe Conway
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