Re: Make TOAST_TUPLES_PER_PAGE configurable per table.

Tom Lane <tgl@sss.pgh.pa.us>

From: Tom Lane <tgl@sss.pgh.pa.us>
To: Jesper Krogh <jesper@krogh.cc>
Cc: PostgreSQL-development Hackers <pgsql-hackers@postgresql.org>
Date: 2010-02-02T00:09:12Z
Lists: pgsql-hackers
Jesper Krogh <jesper@krogh.cc> writes:
> This patch enables users to set TOAST_TUPLES_PER_PAGE with
> ALTER TABLE <table> SET (tuples_per_page = X); .. currently with 1 <= X
> <= 32;

It's not clear to me that fiddling with that is useful unless the toast
tuple size also changes; and unfortunately changing that is much harder,
because it's wired into the addressing of toast data.  See also these
notes:

 * XXX while these can be modified without initdb, some thought needs to be
 * given to needs_toast_table() in toasting.c before unleashing random
 * changes.  Also see LOBLKSIZE in large_object.h, which can *not* be
 * changed without initdb.

			regards, tom lane