Re: [HACKERS] Autovacuum loose ends

Alvaro Herrera wrote:

>On Sun, Jul 24, 2005 at 02:33:38PM -0400, Tom Lane wrote:
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>>Hmm, I wonder whether the minimum shouldn't be 10.  Or even 60.
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>It's ok with me.  What do other people think?
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Effectiely, this is going to be the minimum amount of "down time" for
autovacuum between checking databases, right?  So if the minimum is 10
seconds, and there I have six databases, then it will check each
database at most once per minute?  If so, then I'm not sure what I think
if I have a few hundred databases, 10s might be too long.

>>What's the use-case for having the stat reset feature at all?
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>I don't know.  Maybe the people who added it can tell?
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I don't know either, but this brings up another question.  Stats
wraparound.  The n_tup_ins/upd/del columns in the stats system are
defined as bigint, what happens when the total number of upd for example
exceeds the capacity for bigint, or overflows to negative, anyone have
any idea?

Matt