2010/8/7 Gordon Shannon <gordo169@gmail.com>:
> 1. I delete 10,000 rows.
> pgstattuple.dead_tuple_count -> 10000
>
> 2. I delete 15,000 more rows.
> pgstattuple.dead_tuple_count -> 15000 ??
>
> pgstattuple now appears to count the earlier 10K deleted tuples as no longer
> dead, but free space.
I think it's expected behavior that comes from HOT page reclaim.
The second DELETE not only deleted rows but also removed physical
tuples that were deleted in 1. Missing dead rows were pruned by HOT.
--
Itagaki Takahiro