From: Tom Lane <tgl@sss.pgh.pa.us>
To: "David G. Johnston" <david.g.johnston@gmail.com>
cc: Wells Oliver <wells.oliver@gmail.com>,
        pgsql-admin <pgsql-admin@postgresql.org>
Subject: Re: Setting effective_cache_size in integer form with the 8kb block
 units
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Comments: In-reply-to "David G. Johnston" <david.g.johnston@gmail.com>
	message dated "Wed, 19 Jan 2022 15:15:06 -0700"
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Date: Wed, 19 Jan 2022 17:21:01 -0500
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"David G. Johnston" <david.g.johnston@gmail.com> writes:
> On Wed, Jan 19, 2022 at 2:57 PM Wells Oliver <wells.oliver@gmail.com> wr=
ote:
>> It does. In a cruel twist of fate, RDS parameter groups do not allow
>> "48GB" and want integer values.

> The system operates and calculates memory in binary per the referenced
> documentation so 6,291,456 (I double-checked this).

If you don't trust hand arithmetic, try

regression=3D# set effective_cache_size to '48GB';
SET
regression=3D# select setting from pg_settings where name =3D 'effective_c=
ache_size';
 setting =

---------
 6291456
(1 row)

			regards, tom lane