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
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company
