Re: Autovacuum on by default?

Matthew T. O'Connor wrote:
> Jim C. Nasby wrote:

> >Actually, on a table small enough for the thresholds to kick in it's
> >going to be extremely fast to vacuum anyway, and the table is probably
> >either static or changing very rapidly. I'm wondering if maybe they
> >should just default to 0?
> >
> I assume you are suggesting that the base value be 0? Well for one
> thing if the table doesn't have any rows that will result in constant
> vacuuming of that table, so it needs to be greater than 0. For a small
> table, say 100 rows, there usually isn'tn much performance impact if the
> table if 50% dead space, so I think the base values you suggest are OK,
> but they shouldn't be 0.

Actually Tom suggested some time ago that we should get rid of the base
value completely, i.e. make it 0 forever.

A row with 0 tables would not show any activity in pgstats, so it would
not be vacuumed constantly. Only once after it's truncated.

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Alvaro Herrera http://www.CommandPrompt.com/
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