Horton

Re: generic plans and "initial" pruning

Amit Langote <amitlangote09@gmail.com>

View thread View on postgr.es
From: Amit Langote <amitlangote09@gmail.com>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Tomas Vondra <tomas@vondra.me>, Robert Haas <robertmhaas@gmail.com>, Alvaro Herrera <alvherre@alvh.no-ip.org>, Andres Freund <andres@anarazel.de>, Daniel Gustafsson <daniel@yesql.se>, David Rowley <dgrowleyml@gmail.com>, PostgreSQL Hackers <pgsql-hackers@postgresql.org>, Thom Brown <thom@linux.com>
Date: 2025-02-21T08:07:09Z
Lists: pgsql-hackers 
On Fri, Feb 21, 2025 at 3:36 PM Amit Langote <amitlangote09@gmail.com> wrote:
> On Fri, Feb 21, 2025 at 3:04 PM Tom Lane <tgl@sss.pgh.pa.us> wrote:
> >
> > Amit Langote <amitlangote09@gmail.com> writes:
> > > I pushed the final piece yesterday.
> >
> > trilobite reports that this fails under -DCLOBBER_CACHE_ALWAYS:
> >
> > https://buildfarm.postgresql.org/cgi-bin/show_log.pl?nm=trilobite&dt=2025-02-20%2019%3A37%3A12
>
> Looking, thanks for the heads up.

The short of it is that the cached-plan-inval test in the
delay_execution suite can never be made to work under
CLOBBER_CACHE_ALWAYS. The test assumes that locks on partitions for a
reused generic plan are not taken until InitPlan(). However, under
CLOBBER_CACHE_ALWAYS, generic plans are never reused, so the test's
assumption never holds.

I see two possible ways to address this:

1. Find a way to disable the cached-plan-inval test in
CLOBBER_CACHE_ALWAYS builds. However, I haven't found any other test
that does this.

2. Remove the test altogether, though that might be too drastic.

Thoughts?


--
Thanks, Amit Langote

Commits

  1. Stamp 19beta1.

  2. Revert "Don't lock partitions pruned by initial pruning"

  3. Ensure first ModifyTable rel initialized if all are pruned

  4. Fix bug in cbc127917 to handle nested Append correctly

  5. Remove unstable test suite added by 525392d57

  6. Don't lock partitions pruned by initial pruning

  7. Fix an oversight in cbc127917 to handle MERGE correctly

  8. Track unpruned relids to avoid processing pruned relations

  9. Perform runtime initial pruning outside ExecInitNode()

  10. Move PartitionPruneInfo out of plan nodes into PlannedStmt

  11. Fix setrefs.c's failure to do expression processing on prune steps.

  12. Remove obsolete executor cleanup code

  13. Revert "Move PartitionPruneInfo out of plan nodes into PlannedStmt"

  14. Move PartitioPruneInfo out of plan nodes into PlannedStmt

  15. Refactor and cleanup runtime partition prune code a little

  16. Remove some unnecessary fields from Plan trees.

  17. Remove more redundant relation locking during executor startup.

  18. Shut down Gather's children before shutting down Gather itself.