Обсуждение: collector/autovacuum after crash (8.1beta3)

Hi All,

At system crash or poweroff the autovacuum statistics will be lost,
because this statistics only stored in RAM and saved/restored at
service shutdown/startup.
I think it should be saved periodically and not to be deleted after
crash.


                                -Sygma

Szima Gábor wrote:

> At system crash or poweroff the autovacuum statistics will be lost,
> because this statistics only stored in RAM and saved/restored at
> service shutdown/startup.
> I think it should be saved periodically and not to be deleted after
> crash.

I don't remember why it was that we made the stat file be dropped on
crash recovery, but there was a reason.  I guess you could research the
reason; it was a thread which ended with an autovacuum patch from me.
You could look the CVS logs for the pgstat.c file.

-- 
Alvaro Herrera                        http://www.advogato.org/person/alvherre
"Someone said that it is at least an order of magnitude more work to do
production software than a prototype. I think he is wrong by at least
an order of magnitude."                              (Brian Kernighan)

Alvaro Herrera <alvherre@alvh.no-ip.org> writes:
> Szima G�bor wrote:
>> At system crash or poweroff the autovacuum statistics will be lost,

> I don't remember why it was that we made the stat file be dropped on
> crash recovery, but there was a reason.

The fact that it's not WAL-backed and hence couldn't be trusted.  But
I think he's complaining about the contrib version of autovacuum anyway.
        regards, tom lane