Re: Revitalising VACUUM FULL for 8.3

On Thu, Mar 01, 2007 at 01:05:28PM +0000, Simon Riggs wrote:
> ISTM a radical approach is needed, so I'm very open to discussion about
> this and how we cope.
>
> If we break down the main thoughts into a few parts:
>
> 1. would like a way to CLUSTER/VACUUM FULL where we don't have to move
> all of the tuple versions, just the current ones.
>
> 2. would like a way to compact a table more efficiently
>
> Your idea does (2) in a concurrent manner, which is very good.

Along similar lines, I think it would also be very useful to have a mode
where any time a tuple on the last X pages gets updated it's moved off
of it's existing page in the relation. Kind of like a 'shrink the heap
in the background'. Granted, this probably won't compact as much as
something more aggressive would, but it should be essentially free.
--
Jim Nasby jim(at)nasby(dot)net
EnterpriseDB http://enterprisedb.com 512.569.9461 (cell)