On 08/10/2014 12:22 PM, Simon Riggs wrote:
> On 8 August 2014 16:03, Heikki Linnakangas <hlinnakangas@vmware.com> wrote:
>
>> 1. MMTuple contains the block number of the heap page (range) that the tuple
>> represents. Vacuum is no longer needed to clean up old tuples; when an index
>> tuples is updated, the old tuple is deleted atomically with the insertion of
>> a new tuple and updating the revmap, so no garbage is left behind.
>
> What happens if the transaction that does this aborts? Surely that
> means the new value is itself garbage? What cleans up that?
It's no different from Alvaro's patch. The updated MMTuple covers the
aborted value, but that's OK from a correctnes point of view.
- Heikki