Re: RFC: Making TRUNCATE more "MVCC-safe"

On Wed, Mar 7, 2012 at 10:26 AM, Simon Riggs <simon(at)2ndquadrant(dot)com> wrote:
> On Wed, Mar 7, 2012 at 2:59 PM, Robert Haas <robertmhaas(at)gmail(dot)com> wrote:
>> All true.
>
> So gentlemen, do we think this is worth pursuing further for this release?
>
> I'm sure usual arguments apply all round, so I'll skip that part.

This patch is awfully late to the party, but if we can nail it down
reasonably quickly I guess I'd be in favor of slipping something in.
I am not thrilled with the design as it stands, but bulk loading is a
known and serious pain point for us, so it would be awfully nice to
improve it. I'm not sure whether we should only go as far as setting
HEAP_XMIN_COMMITTED or whether we should actually try to mark the
tuples with FrozenXID. The former has the advantage of (I think) not
requiring any other changes to preserve MVCC semantics while the
latter is, obviously, a bigger performance improvement.

--
Robert Haas
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