Re: Rework the way multixact truncations work

On Mon, Sep 28, 2015 at 5:47 PM, Jim Nasby <Jim.Nasby@bluetreble.com> wrote:
> There was discussion about making this a PANIC instead of a LOG, which I
> think is a good idea... but then there'd need to be some way to not PANIC if
> you were doing an upgrade.

I think you're worrying about a non-problem.  This code has not been
back-patched prior to 9.5, and the legacy truncation code has been
removed in 9.5+.  So it's a complete non-issue right at the moment.
If at some point we back-patch this further, then it potentially
becomes a live issue, but I would like to respectfully inquire what
exactly you think making it a PANIC would accomplish?  There are a lot
of scary things about this patch, but the logic for deciding whether
to perform a legacy truncation is solid as far as I know.

-- 
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
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