Re: Idea for getting rid of VACUUM FREEZE on cold pages - Mailing list pgsql-hackers

From Tom Lane
Subject Re: Idea for getting rid of VACUUM FREEZE on cold pages
Date
Msg-id 20379.1275672959@sss.pgh.pa.us
Whole thread Raw
In response to Re: Idea for getting rid of VACUUM FREEZE on cold pages  (Bruce Momjian <bruce@momjian.us>)
Responses Re: Idea for getting rid of VACUUM FREEZE on cold pages
Re: Idea for getting rid of VACUUM FREEZE on cold pages
List pgsql-hackers
Bruce Momjian <bruce@momjian.us> writes:
> The idea that thousands of Postgres installations are slower just so we
> can occasionally debug xmin/xmax issues seems way off balance to me.

There's no evidence whatsoever that the scope of the problem is that large.

> If people want debugging, let them modify the freeze age settings;  the
> defaults should not favor debugging when there is a measurable cost
> involved.  How many times in the past five years have we even needed
> such debugging information, and also are cases where we could not have
> told the user to change freeze settings to get us that info?

You're missing the point here: this is something we need when trying
to make sense of cases that are hard or impossible to reproduce.
Retroactively changing the freeze policy isn't possible.
        regards, tom lane


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