Tom Lane wrote:
> Bruce Momjian <bruce@momjian.us> writes:
>> Is enlarging the xid field something we should consider for 8.4?
>
> No. We just got the tuple header down to 24 bytes, we are not going
> to give that back and then some.
>
> If you are processing 6K transactions per second, you can afford to
> vacuum every couple days... and probably need to vacuum much more often
> than that anyway, to avoid table bloat.
Speaking of vacuum, hopefully we'll get some sort of dead space map in
8.4. If we keep track of frozen pages there, vacuuming to avoid xid
wraparound will be much cheaper.
-- Heikki Linnakangas EnterpriseDB http://www.enterprisedb.com