It's been pointed out to me that I introduced a bug as part of the
recent optimisation of COPY-after-truncate.
The attached patch fixes this for me on CVS HEAD. It does this by making
an explicit request for relcache hint cleanup at EOXact and takes a more
cautious approach during RelationCacheIn
Please see the attached WIP HOT patch - version 3.2. It now
implements the logic for reusing heap-only dead tuples. When a
HOT-update chain is pruned, the heap-only tuples are marked
LP_DELETE. The lp_offset and lp_len fields in the line pointer are
maintained.
When a backend runs out of free
