Re: more about pg_toast growth

> I doubled that, and it still doesn't work. You are suggesting I
> increase your previous estimate by a factor of 200. Your email of
> 2002-03-13 at 15:16 -0500 suggests a FSM of 50,000 pages allocates "some
> more shared memory. It's surely in the range of a few megabytes..."
> Will a FSM map 200 times larger require 200 times more memory, or is the
> growth nonlinear? How can I calculate this requirement? Without some
> documentation this database is inoperable.
>
> I stand behind my previous statement: if PostgreSQL's unchecked table
> growth can only be prevented by changing an undocumented configuration
> key using an undocumented formula producing undocumented system impact,
> the implementation is flawed.

This does bring up a point that VACUUM alone does not handle all cases
of reusing tuple space. VACUUM FULL is needed occasionally.

--
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