Tatsuhito Kasahara <kasahara.tatsuhito@oss.ntt.co.jp> writes:
> When I tested simple query as following, backend process used much memory
> and not freed until the backend was finished.
> # This is reproduced on PostgreSQL8.3 (PostgreSQL8.3.6 - PostgreSQL8.3.12)
Hmm ... this test case doesn't appear to produce any significant memory
leakage in 8.4 and up. What is happening in 8.3 is that the
CurTransactionContext of each subtransaction becomes nonempty, so it
eats 8K or so even though the snapshot gets released shortly later.
There are plenty of other ways to cause that to happen, though, so I'm
not particularly excited about fixing this one ... especially not in a
stable branch that's not getting a lot of developer testing anymore.
I'm inclined to leave this alone --- I think the risks of patching only
an old branch will outweigh the benefits.
regards, tom lane