Gokulakannan Somasundaram wrote:
> a) When i was looking at the code for freezing heap tuples, i found out the
> following. While freezing we log the complete block(not just the tuples we
> froze).
> b) Again after removing the dead tuples and fragmentation, we log the
> complete block.
Umm, no we don't. In log_heap_freeze, we log an array of offsets, of
those tuples that were frozen.
Perhaps you're been confused by full page writes? If a block hasn't been
modified by last checkpoint, then we do log the whole page for any
operation, including vacuuming and freezing. (except setting hint bits).
--
Heikki Linnakangas
EnterpriseDB http://www.enterprisedb.com