Re: New Object Access Type hooks - Mailing list pgsql-hackers

From Andres Freund
Subject Re: New Object Access Type hooks
Date
Msg-id 20220322230851.wiljffrtojygwcrh@alap3.anarazel.de
Whole thread Raw
In response to Re: New Object Access Type hooks  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-hackers
Hi,

On 2022-03-22 18:41:45 -0400, Tom Lane wrote:
> Mark Dilger <mark.dilger@enterprisedb.com> writes:
> >> On Mar 22, 2022, at 3:20 PM, Andres Freund <andres@anarazel.de> wrote:
> >> Seems like it might actually be good to test that object access hooks work
> >> well in a parallel worker. How about going the other way and explicitly setting
> >> force_parallel_mode = disabled for parts of the test and to enabled for
> >> others?
> 
> > Wouldn't we get differing numbers of NOTICE messages depending on how
> > many parallel workers there are?  Or would you propose setting the
> > number of workers to a small, fixed value?

Yes.


> The value would have to be "1", else you are going to have issues
> with notices from different workers being interleaved differently
> from run to run.

Yea. Possible one could work around those with some effort (using multiple
notification channels maybe), but there seems little to glean from multiple
workers that a single worker wouldn't show.


> You might have that anyway, due to interleaving of leader and worker
> messages.

That part could perhaps be addressed by setting parallel_leader_participation
= 0.

Greetings,

Andres Freund



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