Re: Vacuum, Freeze and Analyze: the big picture

On Sun, Jun 2, 2013 at 2:44 PM, Jeff Janes <jeff.janes@gmail.com> wrote:
> Do we know why anti-wraparound uses so many resources in the first place?
> The default settings seem to be quite conservative to me, even for a system
> that has only a single 5400 rpm hdd (and even more so for any real
> production system that would be used for a many-GB database).
>
> I wonder if there is something simple but currently unknown going on which
> is causing it to damage performance out of all proportion to the resources
> it ought to be using.

I can't rule that out.  Personally, I've always attributed it to the
fact that it's (a) long and (b) I/O-intensive.  But it's not
impossible there could also be bugs lurking.

-- 
Robert Haas
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