Re: executor relation handling

Amit Langote <langote_amit_f8@lab.ntt.co.jp>

From: Amit Langote <Langote_Amit_f8@lab.ntt.co.jp>

To: David Rowley <david.rowley@2ndquadrant.com>

Cc: Jesper Pedersen <jesper.pedersen@redhat.com>, Amit Langote <amitlangote09@gmail.com>, Pg Hackers <pgsql-hackers@postgresql.org>, Tom Lane <tgl@sss.pgh.pa.us>

Date: 2018-09-28T08:28:58Z

Lists: pgsql-hackers

Attachments

v8-0001-Don-t-lock-range-table-relations-in-the-executor.patch (text/plain) patch v8-0001
v8-0002-Remove-useless-fields-from-planner-nodes.patch (text/plain) patch v8-0002
v8-0003-Prune-PlanRowMark-of-relations-that-are-pruned-fr.patch (text/plain) patch v8-0003
v8-0004-Revise-executor-range-table-relation-opening-clos.patch (text/plain) patch v8-0004

On 2018/09/28 17:21, David Rowley wrote:
> On 28 September 2018 at 20:00, Amit Langote
> <Langote_Amit_f8@lab.ntt.co.jp> wrote:
>> I've made minor tweaks, which find in
>> the attached updated patches (a .diff file containing changes from v6 to
>> v7 is also attached).
> 
> Thanks for looking over the changes.
> 
> I've looked at the v6 to v7 diff and it seems all good, apart from:
> 
> + * The following asserts that the necessary lock on the relation
> 
> I think we maybe should switch the word "assert" for "verifies". The
> Assert is just checking we didn't get a NoLock and I don't think
> you're using "assert" meaning the Assert() marco, so likely should be
> changed to avoid confusion.

Okay, I've revised the text in the attached updated patch.

> Apart from that, I see nothing wrong with the patches, so I think we
> should get someone else to look. I'm marking it as ready for
> committer.

Thanks for your time reviewing the patches.

Regards,
Amit

Commits

Avoid O(N^2) cost in ExecFindRowMark().
- f9eb7c14b08d 12.0 landed
Remove some unnecessary fields from Plan trees.
- 52ed730d511b 12.0 landed
Restore sane locking behavior during parallel query.
- 29ef2b310da9 12.0 landed
Remove more redundant relation locking during executor startup.
- f2343653f5b2 12.0 landed
In the executor, use an array of pointers to access the rangetable.
- d73f4c74dd34 12.0 landed
Centralize executor's opening/closing of Relations for rangetable entries.
- 9ddef36278a9 12.0 landed
Change executor to just Assert that table locks were already obtained.
- 9a3cebeaa7fd 12.0 landed
Change rewriter/planner/executor/plancache to depend on RTE rellockmode.
- 6e35939febf8 12.0 landed
Add assertions that we hold some relevant lock during relation open.
- b04aeb0a053e 12.0 landed
Create an RTE field to record the query's lock mode for each relation.
- fdba460a26af 12.0 landed