Re: 8.2 Autovacuum BUG ?

Pallav Kalva wrote:
> Tom Lane wrote:

>> Probably represents freezing of old tuples, which is a WAL-logged
>> operation as of 8.2.  Is it likely that the data is 200M transactions
>> old?
>>
> If nothing changed on these tables how can it freeze old tuples ?
> Does it mean that once it reaches 200M transactions it will do the same
> thing all over again ?

No -- once tuples are frozen, they don't need freezing again (unless
they are modified by UPDATE or DELETE).

> If I am doing just SELECTS on these tables ? how can there be any
> transactions ? or SELECTS considered transactions too ?

Selects are transactions too.  They just don't modify data.

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