Re: REINDEX INDEX results in a crash for an index of pg_class since 9.6

Hi,

On 2019-05-07 10:50:19 -0400, Tom Lane wrote:
> Andres Freund <andres(at)anarazel(dot)de> writes:
> > I for sure thought I earlier had an idea that'd actually work. But
> > either I've lost it, or it didn't actually work. But perhaps somebody
> > else can come up with something based on the above strawman ideas?
>
> Both of those ideas fail if an autovacuum starts up after you're
> done looking.

Well, that's why I had proposed to basically to first lock pg_class, and
then wait for other sessions. Which'd be fine, except that it'd also
create deadlock risks :(.

> My advice is to let it go until we have time to work on getting rid
> of the deadlock issues. If we're successful at that, it might be
> possible to re-enable these tests in the regular regression environment.

Yea, that might be right. I'm planning to leave the tests in until a
bunch of the open REINDEX issues are resolved. Not super likely that
it'd break something, but probably worth anyway?

Greetings,

Andres Freund