Re: autovacuum not prioritising for-wraparound tables

On Thu, Jan 24, 2013 at 5:22 PM, Heikki Linnakangas
<hlinnakangas(at)vmware(dot)com> wrote:
> Backpatching sounds a bit scary. It's not a clear-cut bug, it's just that
> autovacuum could be smarter about its priorities. There are other ways you
> can still bump into the xid-wraparound issue, even with this patch.

I don't think this is a single-priority issue. It's *also* crucial
that small tables
with high "tuple attrition rates" get vacuumed extremely frequently; your system
will bog down, albeit in a different way, if the small tables don't
get vacuumed enough.

This seems to me to involve multiple competing priorities where the
main solution
*I* can think of is to have multiple backends doing autovacuum, and assigning
some to XID activity and others to the "small, needs vacuuming
frequently" tables.
--
When confronted by a difficult problem, solve it by reducing it to the
question, "How would the Lone Ranger handle this?"