[HACKERS] Small FSM is too large

2010-06-20 Thread Simon Riggs

I notice that if I vacuum a 1 row table I get a FSM that is 24576 bytes
in size, or 3 database blocks.

Why is it not 1 block, or better still 0 blocks for such a small table?

-- 
 Simon Riggs   www.2ndQuadrant.com


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Re: [HACKERS] Small FSM is too large

2010-06-20 Thread Heikki Linnakangas

On 20/06/10 13:56, Simon Riggs wrote:

I notice that if I vacuum a 1 row table I get a FSM that is 24576 bytes
in size, or 3 database blocks.

Why is it not 1 block, or better still 0 blocks for such a small table?


It was just less code to write and test that way. The FSM tree is always 
constant height, three levels, to keep things simple.


--
  Heikki Linnakangas
  EnterpriseDB   http://www.enterprisedb.com

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