Re: Idea for getting rid of VACUUM FREEZE on cold pages

Tom Lane wrote:
> 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.

With in-place VACUUM FULL gone in 9.0, will there be as much need for
xmin/xmax forensics?

--  Bruce Momjian  <bruce@momjian.us>        http://momjian.us EnterpriseDB
http://enterprisedb.com
 + None of us is going to be here forever. +