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.

--
  Bruce Momjian                        |  http://candle.pha.pa.us
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