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From: Amit Kapila <amit.kapila16@gmail.com>
Date: Thu, 3 Feb 2022 08:15:16 +0530
Message-ID: <CAA4eK1+uJZ6qYcZxp_A19ZCByhdhui3T3PZ2_ipnJDpwuuzo-w@mail.gmail.com>
Subject: Re: Bugs in pgoutput.c
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>, 
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On Sat, Jan 29, 2022 at 8:32 AM Amit Kapila <amit.kapila16@gmail.com> wrote:
>
> On Thu, Jan 6, 2022 at 3:42 AM Tom Lane <tgl@sss.pgh.pa.us> wrote:
> >
> > Commit 6ce16088b caused me to look at pgoutput.c's handling of
> > cache invalidations, and I was pretty appalled by what I found.
> >
> > * rel_sync_cache_relation_cb does the wrong thing when called for
> > a cache flush (i.e., relid == 0).  Instead of invalidating all
> > RelationSyncCache entries as it should, it will do nothing.
> >
> > * When rel_sync_cache_relation_cb does invalidate an entry,
> > it immediately zaps the entry->map structure, even though that
> > might still be in use (as per the adjacent comment that carefully
> > explains why this isn't safe).  I'm not sure if this could lead
> > to a dangling-pointer core dump, but it sure seems like it could
> > lead to failing to translate tuples that are about to be sent.
> >
> > * Similarly, rel_sync_cache_publication_cb is way too eager to
> > reset the pubactions flags, which would likely lead to failing
> > to transmit changes that we should transmit.
> >
>
> Are you planning to proceed with this patch?
>

Tom, is it okay for you if I go ahead with this patch after some testing?

-- 
With Regards,
Amit Kapila.